Fertilization. Medical search

The fusion of a spermatozoon (SPERMATOZOA) with an OVUM thus resulting in the formation of a ZYGOTE.

An assisted reproductive technique that includes the direct handling and manipulation of oocytes and sperm to achieve fertilization in vitro.

Mature male germ cells derived from SPERMATIDS. As spermatids move toward the lumen of the SEMINIFEROUS TUBULES, they undergo extensive structural changes including the loss of cytoplasm, condensation of CHROMATIN into the SPERM HEAD, formation of the ACROSOME cap, the SPERM MIDPIECE and the SPERM TAIL that provides motility.

Interactive processes between the oocyte (OVUM) and the sperm (SPERMATOZOA) including sperm adhesion, ACROSOME REACTION, sperm penetration of the ZONA PELLUCIDA, and events leading to FERTILIZATION.

A mature haploid female germ cell extruded from the OVARY at OVULATION.

Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).

The transfer of mammalian embryos from an in vivo or in vitro environment to a suitable host to improve pregnancy or gestational outcome in human or animal. In human fertility treatment programs, preimplantation embryos ranging from the 4-cell stage to the blastocyst stage are transferred to the uterine cavity between 3-5 days after FERTILIZATION IN VITRO.

The fertilized OVUM resulting from the fusion of a male and a female gamete.

A tough transparent membrane surrounding the OVUM. It is penetrated by the sperm during FERTILIZATION.

An assisted fertilization technique consisting of the microinjection of a single viable sperm into an extracted ovum. It is used principally to overcome low sperm count, low sperm motility, inability of sperm to penetrate the egg, or other conditions related to male infertility (INFERTILITY, MALE).

Movement characteristics of SPERMATOZOA in a fresh specimen. It is measured as the percentage of sperms that are moving, and as the percentage of sperms with productive flagellar motion such as rapid, linear, and forward progression.

The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.

Somewhat flattened, globular echinoderms, having thin, brittle shells of calcareous plates. They are useful models for studying FERTILIZATION and EMBRYO DEVELOPMENT.

The ratio of the number of conceptions (CONCEPTION) including LIVE BIRTH; STILLBIRTH; and fetal losses, to the mean number of females of reproductive age in a population during a set time period.

The cap-like structure covering the anterior portion of SPERM HEAD. Acrosome, derived from LYSOSOMES, is a membrane-bound organelle that contains the required hydrolytic and proteolytic enzymes necessary for sperm penetration of the egg in FERTILIZATION.

The earliest developmental stage of a fertilized ovum (ZYGOTE) during which there are several mitotic divisions within the ZONA PELLUCIDA. Each cleavage or segmentation yields two BLASTOMERES of about half size of the parent cell. This cleavage stage generally covers the period up to 16-cell MORULA.

Changes that occur to liberate the enzymes of the ACROSOME of a sperm (SPERMATOZOA). Acrosome reaction allows the sperm to penetrate the ZONA PELLUCIDA and enter the OVUM during FERTILIZATION.

Substances or mixtures that are added to the soil to supply nutrients or to make available nutrients already present in the soil, in order to increase plant growth and productivity.

The structural and functional changes by which SPERMATOZOA become capable of oocyte FERTILIZATION. It normally requires exposing the sperm to the female genital tract for a period of time to bring about increased SPERM MOTILITY and the ACROSOME REACTION before fertilization in the FALLOPIAN TUBES can take place.

Diminished or absent ability of a female to achieve conception.

Morphological and physiological development of EMBRYOS.

Preservation of cells, tissues, organs, or embryos by freezing. In histological preparations, cryopreservation or cryofixation is used to maintain the existing form, structure, and chemical composition of all the constituent elements of the specimens.

A post-MORULA preimplantation mammalian embryo that develops from a 32-cell stage into a fluid-filled hollow ball of over a hundred cells. A blastocyst has two distinctive tissues. The outer layer of trophoblasts gives rise to extra-embryonic tissues. The inner cell mass gives rise to the embryonic disc and eventual embryo proper.

Techniques for the artifical induction of ovulation, the rupture of the follicle and release of the ovum.

The inability of the male to effect FERTILIZATION of an OVUM after a specified period of unprotected intercourse. Male sterility is permanent infertility.

Inability to reproduce after a specified period of unprotected intercourse. Reproductive sterility is permanent infertility.

Proteins which are found in eggs (OVA) from any species.

The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.

Endometrial implantation of EMBRYO, MAMMALIAN at the BLASTOCYST stage.

The capacity to conceive or to induce conception. It may refer to either the male or female.

The plasma membrane of the egg.

Morphological and physiological development of EMBRYOS or FETUSES.

A unisexual reproduction without the fusion of a male and a female gamete (FERTILIZATION). In parthenogenesis, an individual is formed from an unfertilized OVUM that did not complete MEIOSIS. Parthenogenesis occurs in nature and can be artificially induced.

The anterior portion of the spermatozoon (SPERMATOZOA) that contains mainly the nucleus with highly compact CHROMATIN material.

Results of conception and ensuing pregnancy, including LIVE BIRTH; STILLBIRTH; SPONTANEOUS ABORTION; INDUCED ABORTION. The outcome may follow natural or artificial insemination or any of the various ASSISTED REPRODUCTIVE TECHNIQUES, such as EMBRYO TRANSFER or FERTILIZATION IN VITRO.

The process by which semen is kept viable outside of the organism from which it was derived (i.e., kept from decay by means of a chemical agent, cooling, or a fluid substitute that mimics the natural state within the organism).

Procedures to obtain viable OOCYTES from the host. Oocytes most often are collected by needle aspiration from OVARIAN FOLLICLES before OVULATION.

The process of germ cell development in the female from the primordial germ cells through OOGONIA to the mature haploid ova (OVUM).

Artificial introduction of SEMEN or SPERMATOZOA into the VAGINA to facilitate FERTILIZATION.

The fluid surrounding the OVUM and GRANULOSA CELLS in the Graafian follicle (OVARIAN FOLLICLE). The follicular fluid contains sex steroids, glycoprotein hormones, plasma proteins, mucopolysaccharides, and enzymes.

Methods pertaining to the generation of new individuals, including techniques used in selective BREEDING, cloning (CLONING, ORGANISM), and assisted reproduction (REPRODUCTIVE TECHNIQUES, ASSISTED).

A subphylum of chordates intermediate between the invertebrates and the true vertebrates. It includes the Ascidians.

Echinoderms having bodies of usually five radially disposed arms coalescing at the center.

The entity of a developing mammal (MAMMALS), generally from the cleavage of a ZYGOTE to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the FETUS.

A pair of highly specialized muscular canals extending from the UTERUS to its corresponding OVARY. They provide the means for OVUM collection, and the site for the final maturation of gametes and FERTILIZATION. The fallopian tube consists of an interstitium, an isthmus, an ampulla, an infundibulum, and fimbriae. Its wall consists of three histologic layers: serous, muscular, and an internal mucosal layer lined with both ciliated and secretory cells.

A type of CELL NUCLEUS division, occurring during maturation of the GERM CELLS. Two successive cell nucleus divisions following a single chromosome duplication (S PHASE) result in daughter cells with half the number of CHROMOSOMES as the parent cells.

The element in plants that contains the female GAMETOPHYTES.

An OOCYTE-containing structure in the cortex of the OVARY. The oocyte is enclosed by a layer of GRANULOSA CELLS providing a nourishing microenvironment (FOLLICULAR FLUID). The number and size of follicles vary depending on the age and reproductive state of the female. The growing follicles are divided into five stages: primary, secondary, tertiary, Graafian, and atretic. Follicular growth and steroidogenesis depend on the presence of GONADOTROPINS.

Extracts of urine from menopausal women that contain high concentrations of pituitary gonadotropins, FOLLICLE STIMULATING HORMONE and LUTEINIZING HORMONE. Menotropins are used to treat infertility. The FSH:LH ratio and degree of purity vary in different preparations.

The discharge of an OVUM from a rupturing follicle in the OVARY.

A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).

The thick, yellowish-white, viscid fluid secretion of male reproductive organs discharged upon ejaculation. In addition to reproductive organ secretions, it contains SPERMATOZOA and their nutrient plasma.

Transfer of preovulatory oocytes from donor to a suitable host. Oocytes are collected, fertilized in vitro, and transferred to a host that can be human or animal.

The granulosa cells of the cumulus oophorus which surround the OVUM in the GRAAFIAN FOLLICLE. At OVULATION they are extruded with OVUM.

A trypsin-like enzyme of spermatozoa which is not inhibited by alpha 1 antitrypsin.

Clinical and laboratory techniques used to enhance fertility in humans and animals.

The technique of maintaining or growing mammalian EMBRYOS in vitro. This method offers an opportunity to observe EMBRYONIC DEVELOPMENT; METABOLISM; and susceptibility to TERATOGENS.

A count of SPERM in the ejaculum, expressed as number per milliliter.

Passive or active movement of SPERMATOZOA from the testicular SEMINIFEROUS TUBULES through the male reproductive tract as well as within the female reproductive tract.

The deposit of SEMEN or SPERMATOZOA into the VAGINA to facilitate FERTILIZATION.

A phylum of the most familiar marine invertebrates. Its class Stelleroidea contains two subclasses, the Asteroidea (the STARFISH or sea stars) and the Ophiuroidea (the brittle stars, also called basket stars and serpent stars). There are 1500 described species of STARFISH found throughout the world. The second class, Echinoidea, contains about 950 species of SEA URCHINS, heart urchins, and sand dollars. A third class, Holothuroidea, comprises about 900 echinoderms known as SEA CUCUMBERS. Echinoderms are used extensively in biological research. (From Barnes, Invertebrate Zoology, 5th ed, pp773-826)

Occurrence or induction of release of more ova than are normally released at the same time in a given species. The term applies to both animals and humans.

Methods used to induce premature oocytes, that are maintained in tissue culture, to progress through developmental stages including to a stage that is competent to undergo FERTILIZATION.

The reproductive organ (GONADS) in female animals. In vertebrates, the ovary contains two functional parts: the OVARIAN FOLLICLE for the production of female germ cells (OOGENESIS); and the endocrine cells (GRANULOSA CELLS; THECA CELLS; and LUTEAL CELLS) for the production of ESTROGENS and PROGESTERONE.

The event that a FETUS is born alive with heartbeats or RESPIRATION regardless of GESTATIONAL AGE. Such liveborn is called a newborn infant (INFANT, NEWBORN).

The total process by which organisms produce offspring. (Stedman, 25th ed)

A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.

The convoluted cordlike structure attached to the posterior of the TESTIS. Epididymis consists of the head (caput), the body (corpus), and the tail (cauda). A network of ducts leaving the testis joins into a common epididymal tubule proper which provides the transport, storage, and maturation of SPERMATOZOA.

A condition of suboptimal concentration of SPERMATOZOA in the ejaculated SEMEN to ensure successful FERTILIZATION of an OVUM. In humans, oligospermia is defined as a sperm count below 20 million per milliliter semen.

A growth from a pollen grain down into the flower style which allows two sperm to pass, one to the ovum within the ovule, and the other to the central cell of the ovule to produce endosperm of SEEDS.

The performance of dissections, injections, surgery, etc., by the use of micromanipulators (attachments to a microscope) that manipulate tiny instruments.

The condition of carrying two or more FETUSES simultaneously.

Diseases involving the FALLOPIAN TUBES including neoplasms (FALLOPIAN TUBE NEOPLASMS); SALPINGITIS; tubo-ovarian abscess; and blockage.

The developmental entity of a fertilized egg (ZYGOTE) in animal species other than MAMMALS. For chickens, use CHICK EMBRYO.

The posterior filiform portion of the spermatozoon (SPERMATOZOA) that provides sperm motility.

Contraceptive methods based on immunological processes and techniques, such as the use of CONTRACEPTIVE VACCINES.

A complication of OVULATION INDUCTION in infertility treatment. It is graded by the severity of symptoms which include OVARY enlargement, multiple OVARIAN FOLLICLES; OVARIAN CYSTS; ASCITES; and generalized EDEMA. The full-blown syndrome may lead to RENAL FAILURE, respiratory distress, and even DEATH. Increased capillary permeability is caused by the vasoactive substances, such as VASCULAR ENDOTHELIAL GROWTH FACTORS, secreted by the overly-stimulated OVARIES.

Undifferentiated cells resulting from cleavage of a fertilized egg (ZYGOTE). Inside the intact ZONA PELLUCIDA, each cleavage yields two blastomeres of about half size of the parent cell. Up to the 8-cell stage, all of the blastomeres are totipotent. The 16-cell MORULA contains outer cells and inner cells.

The emission of SEMEN to the exterior, resulting from the contraction of muscles surrounding the male internal urogenital ducts.

The phase of cell nucleus division following PROMETAPHASE, in which the CHROMOSOMES line up across the equatorial plane of the SPINDLE APPARATUS prior to separation.

The reproductive cells of plants.

Male germ cells derived from the haploid secondary SPERMATOCYTES. Without further division, spermatids undergo structural changes and give rise to SPERMATOZOA.

The male gonad containing two functional parts: the SEMINIFEROUS TUBULES for the production and transport of male germ cells (SPERMATOGENESIS) and the interstitial compartment containing LEYDIG CELLS that produce ANDROGENS.

Compounds which increase the capacity to conceive in females.

Substances that provide protection against the harmful effects of freezing temperatures.

The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)

Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.

Proteins found in SEMEN. Major seminal plasma proteins are secretory proteins from the male sex accessory glands, such as the SEMINAL VESICLES and the PROSTATE. They include the seminal vesicle-specific antigen, an ejaculate clotting protein; and the PROSTATE-SPECIFIC ANTIGEN, a protease and an esterase.

The fertilizing element of plants that contains the male GAMETOPHYTES.

Elements of limited time intervals, contributing to particular results or situations.

A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.

The maturing process of SPERMATOZOA after leaving the testicular SEMINIFEROUS TUBULES. Maturation in SPERM MOTILITY and FERTILITY takes place in the EPIDIDYMIS as the sperm migrate from caput epididymis to cauda epididymis.

A species of the true toads, Bufonidae, found in South America.

The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.

Expulsion of the product of FERTILIZATION before completing the term of GESTATION and without deliberate interference.

The quality of SEMEN, an indicator of male fertility, can be determined by semen volume, pH, sperm concentration (SPERM COUNT), total sperm number, sperm viability, sperm vigor (SPERM MOTILITY), normal sperm morphology, ACROSOME integrity, and the concentration of WHITE BLOOD CELLS.

Women who allow themselves to be impregnated with the understanding that the offspring are to be given over to the parents who have commissioned the surrogate.

An early embryo that is a compact mass of about 16 BLASTOMERES. It resembles a cluster of mulberries with two types of cells, outer cells and inner cells. Morula is the stage before BLASTULA in non-mammalian animals or a BLASTOCYST in mammals.

Hormones that stimulate gonadal functions such as GAMETOGENESIS and sex steroid hormone production in the OVARY and the TESTIS. Major gonadotropins are glycoproteins produced primarily by the adenohypophysis (GONADOTROPINS, PITUITARY) and the placenta (CHORIONIC GONADOTROPIN). In some species, pituitary PROLACTIN and PLACENTAL LACTOGEN exert some luteotropic activities.

Procedures to obtain viable sperm from the male reproductive tract, including the TESTES, the EPIDIDYMIS, or the VAS DEFERENS.

The removal of secretions, gas or fluid from hollow or tubular organs or cavities by means of a tube and a device that acts on negative pressure.

Sexual activities of animals.

Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).

The process of germ cell development in the male from the primordial germ cells, through SPERMATOGONIA; SPERMATOCYTES; SPERMATIDS; to the mature haploid SPERMATOZOA.

An exotic species of the family CYPRINIDAE, originally from Asia, that has been introduced in North America. They are used in embryological studies and to study the effects of certain chemicals on development.

A potent synthetic analog of GONADOTROPIN-RELEASING HORMONE with D-serine substitution at residue 6, glycine10 deletion, and other modifications.

Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.

An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.

The potential of the FETUS to survive outside the UTERUS after birth, natural or induced. Fetal viability depends largely on the FETAL ORGAN MATURITY, and environmental conditions.

The transformation of a liquid to a glassy solid i.e., without the formation of crystals during the cooling process.

Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)

Chemical agents that increase the permeability of biological or artificial lipid membranes to specific ions. Most ionophores are relatively small organic molecules that act as mobile carriers within membranes or coalesce to form ion permeable channels across membranes. Many are antibiotics, and many act as uncoupling agents by short-circuiting the proton gradient across mitochondrial membranes.

A decapeptide that stimulates the synthesis and secretion of both pituitary gonadotropins, LUTEINIZING HORMONE and FOLLICLE STIMULATING HORMONE. GnRH is produced by neurons in the septum PREOPTIC AREA of the HYPOTHALAMUS and released into the pituitary portal blood, leading to stimulation of GONADOTROPHS in the ANTERIOR PITUITARY GLAND.

The 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids.

A group of simple proteins that yield basic amino acids on hydrolysis and that occur combined with nucleic acid in the sperm of fish. Protamines contain very few kinds of amino acids. Protamine sulfate combines with heparin to form a stable inactive complex; it is used to neutralize the anticoagulant action of heparin in the treatment of heparin overdose. (From Merck Index, 11th ed; Martindale, The Extra Pharmacopoeia, 30th ed, p692)

Ducts that serve exclusively for the passage of eggs from the ovaries to the exterior of the body. In non-mammals, they are termed oviducts. In mammals, they are highly specialized and known as FALLOPIAN TUBES.

Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

Signal transduction mechanisms whereby calcium mobilization (from outside the cell or from intracellular storage pools) to the cytoplasm is triggered by external stimuli. Calcium signals are often seen to propagate as waves, oscillations, spikes, sparks, or puffs. The calcium acts as an intracellular messenger by activating calcium-responsive proteins.

The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.

Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.

A technique that came into use in the mid-1980's for assisted conception in infertile women with normal fallopian tubes. The protocol consists of hormonal stimulation of the ovaries, followed by laparoscopic follicular aspiration of oocytes, and then the transfer of sperm and oocytes by catheterization into the fallopian tubes.

A genus of SEA URCHINS in the family Toxopneustidae possessing trigeminate ambulacral plating.

The process of germ cell development from the primordial GERM CELLS to the mature haploid GAMETES: ova in the female (OOGENESIS) or sperm in the male (SPERMATOGENESIS).

A potent synthetic agonist of GONADOTROPIN-RELEASING HORMONE with 3-(2-naphthyl)-D-alanine substitution at residue 6. Nafarelin has been used in the treatments of central PRECOCIOUS PUBERTY and ENDOMETRIOSIS.

The reproductive cells in multicellular organisms at various stages during GAMETOGENESIS.

An enzyme that catalyzes the random hydrolysis of 1,4-linkages between N-acetyl-beta-D-glucosamine and D-glucuronate residues in hyaluronate. (From Enzyme Nomenclature, 1992) There has been use as ANTINEOPLASTIC AGENTS to limit NEOPLASM METASTASIS.

Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.

The age of the mother in PREGNANCY.

Determination of the nature of a pathological condition or disease in the OVUM; ZYGOTE; or BLASTOCYST prior to implantation. CYTOGENETIC ANALYSIS is performed to determine the presence or absence of genetic disease.

A phylum of metazoan invertebrates comprising the segmented worms, and including marine annelids (POLYCHAETA), freshwater annelids, earthworms (OLIGOCHAETA), and LEECHES. Only the leeches are of medical interest. (Dorland, 27th ed)

Gonadotropins secreted by the pituitary or the placenta in horses. This term generally refers to the gonadotropins found in the pregnant mare serum, a rich source of equine CHORIONIC GONADOTROPIN; LUTEINIZING HORMONE; and FOLLICLE STIMULATING HORMONE. Unlike that in humans, the equine LUTEINIZING HORMONE, BETA SUBUNIT is identical to the equine choronic gonadotropin, beta. Equine gonadotropins prepared from pregnant mare serum are used in reproductive studies.

Glycosidic antibiotic from Streptomyces griseus used as a fluorescent stain of DNA and as an antineoplastic agent.

Nutritive tissue of the seeds of flowering plants that surrounds the EMBRYOS. It is produced by a parallel process of fertilization in which a second male gamete from the pollen grain fuses with two female nuclei within the embryo sac. The endosperm varies in ploidy and contains reserves of starch, oils, and proteins, making it an important source of human nutrition.

A division of predominantly marine EUKARYOTA, commonly known as brown algae, having CHROMATOPHORES containing carotenoid PIGMENTS, BIOLOGICAL. ALGINATES and phlorotannins occur widely in all major orders. They are considered the most highly evolved algae because of their well-developed multicellular organization and structural complexity.

A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.

The fundamental dispositions and traits of humans. (Merriam-Webster's Collegiate Dictionary, 10th ed)

The reproductive organs of plants.

A condition of having no sperm present in the ejaculate (SEMEN).

Methods of maintaining or growing biological materials in controlled laboratory conditions. These include the cultures of CELLS; TISSUES; organs; or embryo in vitro. Both animal and plant tissues may be cultured by a variety of methods. Cultures may derive from normal or abnormal tissues, and consist of a single cell type or mixed cell types.

The point at which religious ensoulment or PERSONHOOD is considered to begin.

A major gonadotropin secreted by the human adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and the LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. The alpha subunit is common in the three human pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.

The state that distinguishes organisms from inorganic matter, manifested by growth, metabolism, reproduction, and adaptation. It includes the course of existence, the sum of experiences, the mode of existing, or the fact of being. Over the centuries inquiries into the nature of life have crossed the boundaries from philosophy to biology, forensic medicine, anthropology, etc., in creative as well as scientific literature. (Random House Unabridged Dictionary, 2d ed; Dr. James H. Cassedy, NLM History of Medicine Division)

Two individuals derived from two FETUSES that were fertilized at or about the same time, developed in the UTERUS simultaneously, and born to the same mother. Twins are either monozygotic (TWINS, MONOZYGOTIC) or dizygotic (TWINS, DIZYGOTIC).

A technique in assisted reproduction (REPRODUCTIVE TECHNIQUES, ASSISTED) consisting of hormonal stimulation of the ovaries, follicular aspiration of preovulatory oocytes, in-vitro fertilization, and intrafallopian transfer of zygotes at the pronuclear stage (before cleavage).

Methods for controlling genetic SEX of offspring.

The transfer of POLLEN grains (male gametes) to the plant ovule (female gamete).

Glycoproteins found on the membrane or surface of cells.

A potentially life-threatening condition in which EMBRYO IMPLANTATION occurs outside the cavity of the UTERUS. Most ectopic pregnancies (>96%) occur in the FALLOPIAN TUBES, known as TUBAL PREGNANCY. They can be in other locations, such as UTERINE CERVIX; OVARY; and abdominal cavity (PREGNANCY, ABDOMINAL).

A potent synthetic long-acting agonist of GONADOTROPIN-RELEASING HORMONE that regulates the synthesis and release of pituitary gonadotropins, LUTEINIZING HORMONE and FOLLICLE STIMULATING HORMONE.

The period of the MENSTRUAL CYCLE representing follicular growth, increase in ovarian estrogen (ESTROGENS) production, and epithelial proliferation of the ENDOMETRIUM. Follicular phase begins with the onset of MENSTRUATION and ends with OVULATION.

Cellular proteins encoded by the c-mos genes (GENES, MOS). They function in the cell cycle to maintain MATURATION PROMOTING FACTOR in the active state and have protein-serine/threonine kinase activity. Oncogenic transformation can take place when c-mos proteins are expressed at the wrong time.

The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.

Sexual union of a male and a female in non-human species.

Embryonic and fetal development that takes place in an artificial environment in vitro.

Agglutination of spermatozoa by antibodies or autoantibodies.

Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.

Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.

Human artificial insemination in which the husband's semen is used.

The number of births in a given population per year or other unit of time.

Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.

Minute cells produced during development of an OOCYTE as it undergoes MEIOSIS. A polar body contains one of the nuclei derived from the first or second meiotic CELL DIVISION. Polar bodies have practically no CYTOPLASM. They are eventually discarded by the oocyte. (from King & Stansfield, A Dictionary of Genetics, 4th ed)

The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.

Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.

A class in the phylum MOLLUSCA comprised of SNAILS and slugs. The former have coiled external shells and the latter usually lack shells.

Liquids transforming into solids by the removal of heat.

Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.

Human artificial insemination in which the semen used is that of a man other than the woman's husband.

Warm-blooded vertebrate animals belonging to the class Mammalia, including all that possess hair and suckle their young.

The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.

Deliberate breeding of two different individuals that results in offspring that carry part of the genetic material of each parent. The parent organisms must be genetically compatible and may be from different varieties or closely related species.

Methods of implanting a CELL NUCLEUS from a donor cell into an enucleated acceptor cell.

Intracellular messenger formed by the action of phospholipase C on phosphatidylinositol 4,5-bisphosphate, which is one of the phospholipids that make up the cell membrane. Inositol 1,4,5-trisphosphate is released into the cytoplasm where it releases calcium ions from internal stores within the cell's endoplasmic reticulum. These calcium ions stimulate the activity of B kinase or calmodulin.

A type C phospholipase with specificity towards PHOSPHATIDYLINOSITOLS that contain INOSITOL 1,4,5-TRISPHOSPHATE. Many of the enzymes listed under this classification are involved in intracellular signaling.

A condition in which functional endometrial tissue is present outside the UTERUS. It is often confined to the PELVIS involving the OVARY, the ligaments, cul-de-sac, and the uterovesical peritoneum.

Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.

Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.

A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.

Three individuals derived from three FETUSES that were fertilized at or about the same time, developed in the UTERUS simultaneously, and born to the same mother.

Chemical agents that increase the permeability of CELL MEMBRANES to CALCIUM ions.

The period in the MENSTRUAL CYCLE that follows OVULATION, characterized by the development of CORPUS LUTEUM, increase in PROGESTERONE production by the OVARY and secretion by the glandular epithelium of the ENDOMETRIUM. The luteal phase begins with ovulation and ends with the onset of MENSTRUATION.

A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.

The chromosomal constitution of cells which deviate from the normal by the addition or subtraction of CHROMOSOMES, chromosome pairs, or chromosome fragments. In a normally diploid cell (DIPLOIDY) the loss of a chromosome pair is termed nullisomy (symbol: 2N-2), the loss of a single chromosome is MONOSOMY (symbol: 2N-1), the addition of a chromosome pair is tetrasomy (symbol: 2N+2), the addition of a single chromosome is TRISOMY (symbol: 2N+1).

A potent synthetic long-acting agonist of GONADOTROPIN-RELEASING HORMONE with D-tryptophan substitution at residue 6.

The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.

The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.

Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.

The techniques used to select and/or place only one embryo from FERTILIZATION IN VITRO into the uterine cavity to establish a singleton pregnancy.

RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.

A polyvinyl polymer of variable molecular weight; used as suspending and dispersing agent and vehicle for pharmaceuticals; also used as blood volume expander.

Experimentation on, or using the organs or tissues from, a human or other mammalian conceptus during the prenatal stage of development that is characterized by rapid morphological changes and the differentiation of basic structures. In humans, this includes the period from the time of fertilization to the end of the eighth week after fertilization.

The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.

A plant genus of the family POACEAE that is used for forage.

A class in the phylum MOLLUSCA comprised of mussels; clams; OYSTERS; COCKLES; and SCALLOPS. They are characterized by a bilaterally symmetrical hinged shell and a muscular foot used for burrowing and anchoring.

An ionophorous, polyether antibiotic from Streptomyces chartreusensis. It binds and transports CALCIUM and other divalent cations across membranes and uncouples oxidative phosphorylation while inhibiting ATPase of rat liver mitochondria. The substance is used mostly as a biochemical tool to study the role of divalent cations in various biological systems.

The state or condition of being a human individual accorded moral and/or legal rights. Criteria to be used to determine this status are subject to debate, and range from the requirement of simply being a human organism to such requirements as that the individual be self-aware and capable of rational thought and moral agency.

An ethylmercury-sulfidobenzoate that has been used as a preservative in VACCINES; ANTIVENINS; and OINTMENTS. It was formerly used as a topical antiseptic. It degrades to ethylmercury and thiosalicylate.

A species of nematode that is widely used in biological, biochemical, and genetic studies.

Liquid components of living organisms.

Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.

The hollow thick-walled muscular organ in the female PELVIS. It consists of the fundus (the body) which is the site of EMBRYO IMPLANTATION and FETAL DEVELOPMENT. Beyond the isthmus at the perineal end of fundus, is CERVIX UTERI (the neck) opening into VAGINA. Beyond the isthmi at the upper abdominal end of fundus, are the FALLOPIAN TUBES.

Prolonged mating in prairie voles (Microtus ochrogaster) increases likelihood of ovulation and embryo number. (1/2757)

Prairie voles are induced ovulators that mate frequently in brief bouts over a period of approximately 24 h. We examined 1) impact of mating duration on ovulation and embryo number, 2) incidence of fertilization, 3) temporal pattern of embryo development, 4) embryo progression through the reproductive tract over time, and 5) embryo development in culture. Mating was videotaped to determine first copulation, and the ovaries were examined and the reproductive tracts flushed at 6, 8, 10, 12, 16, 20, and 24 h and 2, 3, and 4 days after first copulation. The number of mature follicles and fresh corpora lutea and the number and developmental stage of embryos were quantified. One, two-, and four-cell embryos were cultured in Whitten's medium. Mature follicles were present at the earliest time examined (6 h). Thirty-eight percent of females that had been paired for < 12 h after the first copulation ovulated, whereas all females paired >/= 12 h after the first copulation ovulated. Virtually all (> 99%) oocytes recovered from females paired for >/= 12 h after first copulation were fertilized. Pairing time after first copulation and mean copulation-bout duration were significant (p < 0.05) determinants of embryo number. Embryos entered the uterine horns and implanted on Days 3 and 4, respectively, after first copulation (Day 0). Embryos cultured in vitro underwent approximately one cell division per day, a rate similar to that in vivo. We conclude that prairie voles ovulate reliably after pairing for >/= 12 h, although some females showed exceptional sensitivity not predicted by the variables quantified. Prolonged mating for longer than 12 h increased the total embryos produced. This mechanism likely has adaptive significance for increasing offspring number. (+info)

Male gametic cell-specific gene expression in flowering plants. (2/2757)

The role of the male gamete-the sperm cell-in the process of fertilization is to recognize, adhere to, and fuse with the female gamete. These highly specialized functions are expected to be controlled by activation of a unique set of genes. However, male gametic cells traditionally have been regarded as transcriptionally quiescent because of highly condensed chromatin and a very reduced amount of cytoplasm. Here, we provide evidence for male gamete-specific gene expression in flowering plants. We identified and characterized a gene, LGC1, which was shown to be expressed exclusively in the male gametic cells. The gene product of LGC1 was localized at the surface of male gametic cells, suggesting a possible role in sperm-egg interactions. These findings represent an important step toward defining the molecular mechanisms of male gamete development and the cellular processes involved in fertilization of flowering plants. (+info)

Treatment of mouse oocytes with PI-PLC releases 70-kDa (pI 5) and 35- to 45-kDa (pI 5.5) protein clusters from the egg surface and inhibits sperm-oolemma binding and fusion. (3/2757)

The effect of phosphatidyinositol-specific phospholipase C (PI-PLC) on mouse sperm-egg interaction was investigated in this study to determine if glycosyl-phosphatidylinositol (GPI)-anchored proteins are involved in mammalian fertilization. When both sperm and zona-intact oocytes were pretreated with a highly purified preparation of PI-PLC and coincubated, there was no significant effect on sperm-zona pellucida binding; however, fertilization was reduced from 59.6% (control group) to 2.8% (treatment group). A similar reduction in fertilization rates was found when zona-intact oocytes were treated with PI-PLC and washed prior to incubation with untreated sperm. The effect of PI-PLC on sperm binding and fusion with zona-free oocytes was then investigated. Treatment of sperm with PI-PLC had no significant effect on sperm-egg binding or fusion. However, treatment of eggs with PI-PLC significantly reduced sperm-egg binding and fusion from 6.2 bound and 2.1 fused sperm per egg in the control group to 2.1 bound and 0.02 fused sperm per egg in the treatment group. This decrease in sperm-egg binding and fusion depended on the dose of PI-PLC employed, with a maximal inhibitory effect on binding and fusion at 5 and 1 U/ml, respectively. PI-PLC-treated oocytes could be artificially activated by calcium ionophore, demonstrating that the oocytes were functionally viable following treatment. Furthermore, treatment of oocytes with PI-PLC did not reduce the immunoreactivity of the non-GPI-anchored egg surface integrin, alpha6beta1. Taken together, these observations support the hypothesis that PI-PLC affects fertilization by specifically releasing GPI-anchored proteins from the oolemma. In order to identify the oolemmal GPI-anchored proteins involved in fertilization, egg surface proteins were labeled with sulfo-NHS biotin, treated with PI-PLC, and analyzed by two-dimensional gel electrophoresis followed by avidin blotting. A prominent high-molecular-weight protein cluster (approximately 70 kDa, pI 5) and a lower molecular weight (approximately 35-45 kDa, pI 5.5) protein cluster were released from the oolemmal surface as a result of PI-PLC treatment. It is likely that these GPI-anchored egg surface proteins are required for sperm-egg binding and fusion. (+info)

Mutations in FIE, a WD polycomb group gene, allow endosperm development without fertilization. (4/2757)

A fundamental problem in biology is to understand how fertilization initiates reproductive development. Higher plant reproduction is unique because two fertilization events are required for sexual reproduction. First, a sperm must fuse with the egg to form an embryo. A second sperm must then fuse with the adjacent central cell nucleus that replicates to form an endosperm, which is the support tissue required for embryo and/or seedling development. Here, we report cloning of the Arabidopsis FERTILIZATION-INDEPENDENT ENDOSPERM (FIE) gene. The FIE protein is a homolog of the WD motif-containing Polycomb proteins from Drosophila and mammals. These proteins function as repressors of homeotic genes. A female gametophyte with a loss-of-function allele of fie undergoes replication of the central cell nucleus and initiates endosperm development without fertilization. These results suggest that the FIE Polycomb protein functions to suppress a critical aspect of early plant reproduction, namely, endosperm development, until fertilization occurs. (+info)

Activation of Xenopus eggs by proteases: possible involvement of a sperm protease in fertilization. (5/2757)

Egg activation in cross-fertilization between Xenopus eggs and Cynops sperm may be caused by a protease activity against Boc-Gly-Arg-Arg-MCA in the sperm acrosome. To determine the role of the sperm protease in fertilization, the protease was purified from Cynops sperm using several chromatographic techniques. We found that purified sperm protease readily hydrolyzes Boc-Gly-Arg-Arg-MCA and Z-Arg-Arg-MCA, that protease activity was inhibited by the trypsin inhibitors aprotinin and leupeptin, and that not only the purified protease, but also cathepsin B, induces activation in Xenopus eggs. We inseminated unfertilized Xenopus eggs with homologous sperm in the presence of various peptidyl MCA substrates or protease inhibitors and demonstrated that trypsin inhibitors or MCA substrates containing Arg-Arg-MCA reversibly inhibited fertilization of both fully jellied and denuded eggs. Sperm motility was not affected by the reagents. An extract obtained from Xenopus sperm showed hydrolytic activity against Boc-Gly-Arg-Arg-MCA, Z-Arg-Arg-MCA, and Arg-MCA. These results suggest that the tryptic protease in Xenopus sperm is involved in fertilization, most likely by participating in egg activation. (+info)

Evidence that a starfish egg Src family tyrosine kinase associates with PLC-gamma1 SH2 domains at fertilization. (6/2757)

The initiation of calcium release at fertilization in the eggs of most animals relies on the production of IP3, implicating the activation of phospholipase C. Recent work has demonstrated that injection of PLC-gamma SH2 domain fusion proteins into starfish eggs specifically inhibits the initiation of calcium release in response to sperm, indicating that PLC-gamma is necessary for Ca2+ release at fertilization [Carroll et al. (1997) J. Cell Biol. 138, 1303-1311]. Here we investigate how PLC-gamma may be activated, by using the PLC-gamma SH2 domain fusion protein as an affinity matrix to identify interacting proteins. A tyrosine kinase activity and an egg protein of ca. Mr 58 K that is recognized by an antibody directed against Src family tyrosine kinases associate with PLC-gamma SH2 domains in a fertilization-dependent manner. These associations are detected by 15 s postfertilization, consistent with a function in releasing Ca2+. Calcium ionophore treatment of eggs did not cause association of the kinase activity or of the Src family protein with the PLC-gamma SH2 domains. These data identify an egg Src family tyrosine kinase as a potential upstream regulator of PLC-gamma in the activation of starfish eggs. (+info)

Na+/H+ antiporter activity in hamster embryos is activated during fertilization. (7/2757)

This study characterized the activation of the regulatory activity of the Na+/H+ antiporter during fertilization of hamster embryos. Hamster oocytes appeared to lack any mechanism for the regulation of intracellular pH in the acid range. Similarly, no Na+/H+ antiporter activity could be detected in embryos that were collected from the reproductive tract between 1 and 5 h post-egg activation (PEA). Activity of the Na+/H+ antiporter was first detected in embryos collected at 5.5 h PEA and gradually increased to reach maximal activity in embryos collected at 7 h PEA. Parthenogenetically activated one-cell and two-cell embryos demonstrate Na+/H+ antiporter activity, indicating that antiporter activity is maternally derived and initiated by activation of the egg. The inability of cycloheximide, colchicine, or cytochalasin D to affect initiation of antiporter activity indicates that antiporter appearance is not dependent on the synthesis of new protein or recruitment of existing protein to the cell membrane. In contrast, incubation of one-cell embryos with sphingosine did inhibit the appearance of Na+/H+ antiporter activity, showing that inhibition of normal protein kinase C activity is detrimental to antiporter function. Furthermore, incubation of oocytes with a phorbol ester which stimulates protein kinase C activity induced Na+/H+ antiporter activity in oocytes in which the activity was previously absent. Incubation with an intracellular calcium chelator also reduced the appearance of antiporter activity. Taken together, these data indicate that the appearance of Na+/H+ antiporter activity following egg activation may be due, at least in part, to regulation by protein kinase C and intracellular calcium levels. (+info)

Nucleo-cytoplasmic interactions that control nuclear envelope breakdown and entry into mitosis in the sea urchin zygote. (8/2757)

In sea urchin zygotes and mammalian cells nuclear envelope breakdown (NEB) is not driven simply by a rise in cytoplasmic cyclin dependent kinase 1-cyclin B (Cdk1-B) activity; the checkpoint monitoring DNA synthesis can prevent NEB in the face of mitotic levels of Cdk1-B. Using sea urchin zygotes we investigated whether this checkpoint prevents NEB by restricting import of regulatory proteins into the nucleus. We find that cyclin B1-GFP accumulates in nuclei that cannot complete DNA synthesis and do not break down. Thus, this checkpoint limits NEB downstream of both the cytoplasmic activation and nuclear accumulation of Cdk1-B1. In separate experiments we fertilize sea urchin eggs with sperm whose DNA has been covalently cross-linked to inhibit replication. When the pronuclei fuse, the resulting zygote nucleus does not break down for >180 minutes (equivalent to three cell cycles), even though Cdk1-B activity rises to greater than mitotic levels. If pronuclear fusion is prevented, then the female pronucleus breaks down at the normal time (average 68 minutes) and the male pronucleus with cross-linked DNA breaks down 16 minutes later. This male pronucleus has a functional checkpoint because it does not break down for >120 minutes if the female pronucleus is removed just prior to NEB. These results reveal the existence of an activity released by the female pronucleus upon its breakdown, that overrides the checkpoint in the male pronucleus and induces NEB. Microinjecting wheat germ agglutinin into binucleate zygotes reveals that this activity involves molecules that must be actively translocated into the male pronucleus. (+info)

Causes of Female Infertility
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There are several potential causes of female infertility, including:

1. Hormonal imbalances: Disorders such as polycystic ovary syndrome (PCOS), thyroid dysfunction, and premature ovarian failure can affect hormone levels and ovulation.
2. Ovulatory disorders: Problems with ovulation, such as anovulation or oligoovulation, can make it difficult to conceive.
3. Tubal damage: Damage to the fallopian tubes due to pelvic inflammatory disease, ectopic pregnancy, or surgery can prevent the egg from traveling through the tube and being fertilized.
4. Endometriosis: This condition occurs when tissue similar to the lining of the uterus grows outside of the uterus, causing inflammation and scarring that can lead to infertility.
5. Fibroids: Noncancerous growths in the uterus can interfere with implantation of a fertilized egg or disrupt ovulation.
6. Pelvic adhesions: Scar tissue in the pelvis can cause fallopian tubes to become damaged or blocked, making it difficult for an egg to travel through the tube and be fertilized.
7. Uterine or cervical abnormalities: Abnormalities such as a bicornuate uterus or a narrow cervix can make it difficult for a fertilized egg to implant in the uterus.
8. Age: A woman's age can affect her fertility, as the quality and quantity of her eggs decline with age.
9. Lifestyle factors: Factors such as smoking, excessive alcohol consumption, and being overweight or underweight can affect fertility.
10. Stress: Chronic stress can disrupt hormone levels and ovulation, making it more difficult to conceive.

It's important to note that many of these factors can be treated with medical assistance, such as medication, surgery, or assisted reproductive technology (ART) like in vitro fertilization (IVF). If you are experiencing difficulty getting pregnant, it is recommended that you speak with a healthcare provider to determine the cause of your infertility and discuss potential treatment options.

Male infertility can be caused by a variety of factors, including:

1. Low sperm count or poor sperm quality: This is one of the most common causes of male infertility. Sperm count is typically considered low if less than 15 million sperm are present in a sample of semen. Additionally, sperm must be of good quality to fertilize an egg successfully.
2. Varicocele: This is a swelling of the veins in the scrotum that can affect sperm production and quality.
3. Erectile dysfunction: Difficulty achieving or maintaining an erection can make it difficult to conceive.
4. Premature ejaculation: This can make it difficult for the sperm to reach the egg during sexual intercourse.
5. Blockages or obstructions: Blockages in the reproductive tract, such as a blockage of the epididymis or vas deferens, can prevent sperm from leaving the body during ejaculation.
6. Retrograde ejaculation: This is a condition in which semen is released into the bladder instead of being expelled through the penis during ejaculation.
7. Hormonal imbalances: Imbalances in hormones such as testosterone and inhibin can affect sperm production and quality.
8. Medical conditions: Certain medical conditions, such as diabetes, hypogonadism, and hyperthyroidism, can affect fertility.
9. Lifestyle factors: Factors such as smoking, excessive alcohol consumption, and stress can all impact fertility.
10. Age: Male fertility declines with age, especially after the age of 40.

There are several treatment options for male infertility, including:

1. Medications to improve sperm count and quality
2. Surgery to repair blockages or obstructions in the reproductive tract
3. Artificial insemination (IUI) or in vitro fertilization (IVF) to increase the chances of conception
4. Donor sperm
5. Assisted reproductive technology (ART) such as ICSI (intracytoplasmic sperm injection)
6. Hormone therapy to improve fertility
7. Lifestyle changes such as quitting smoking and alcohol, losing weight, and reducing stress.

It's important to note that male infertility is a common condition and there are many treatment options available. If you're experiencing difficulty conceiving, it's important to speak with a healthcare provider to determine the cause of infertility and discuss potential treatment options.

Infertility can be classified into two main categories:

1. Primary infertility: This type of infertility occurs when a couple has not been able to conceive a child after one year of regular sexual intercourse, and there is no known cause for the infertility.
2. Secondary infertility: This type of infertility occurs when a couple has been able to conceive at least once before but is now experiencing difficulty in conceiving again.

There are several factors that can contribute to infertility, including:

1. Age: Women's fertility declines with age, especially after the age of 35.
2. Hormonal imbalances: Imbalances of hormones such as progesterone, estrogen, and thyroid hormones can affect ovulation and fertility.
3. Polycystic ovary syndrome (PCOS): A common condition that affects ovulation and can cause infertility.
4. Endometriosis: A condition in which the tissue lining the uterus grows outside the uterus, causing inflammation and scarring that can lead to infertility.
5. Male factor infertility: Low sperm count, poor sperm quality, and blockages in the reproductive tract can all contribute to infertility.
6. Lifestyle factors: Smoking, excessive alcohol consumption, being overweight or underweight, and stress can all affect fertility.
7. Medical conditions: Certain medical conditions such as diabetes, hypertension, and thyroid disorders can affect fertility.
8. Uterine or cervical abnormalities: Abnormalities in the shape or structure of the uterus or cervix can make it difficult for a fertilized egg to implant in the uterus.
9. Previous surgeries: Surgeries such as hysterectomy, tubal ligation, and cesarean section can affect fertility.
10. Age: Both male and female age can impact fertility, with a decline in fertility beginning in the mid-30s and a significant decline after age 40.

It's important to note that many of these factors can be treated with medical interventions or lifestyle changes, so it's important to speak with a healthcare provider if you are experiencing difficulty getting pregnant.

There are several possible causes of oligospermia, including:

* Hormonal imbalances
* Varicocele (a swelling of the veins in the scrotum)
* Infections such as epididymitis or prostatitis
* Blockages such as a vasectomy or epididymal obstruction
* Certain medications such as anabolic steroids and chemotherapy drugs
* Genetic disorders
* Environmental factors such as exposure to toxins or radiation

Symptoms of oligospermia may include:

* Difficulty getting an erection
* Premature ejaculation
* Low sex drive
* Painful ejaculation

Diagnosis of oligospermia typically involves a physical exam, medical history, and semen analysis. Treatment will depend on the underlying cause of the condition, but may include medications to improve sperm count and quality, surgery to correct blockages or varicoceles, or assisted reproductive technologies such as in vitro fertilization (IVF).

It's important to note that a low sperm count does not necessarily mean a man is infertile. However, it can make it more difficult to conceive a child. With appropriate treatment and lifestyle changes, some men with oligospermia may be able to improve their fertility and have children.

There are several types of fallopian tube diseases, including:

1. Hydrosalpinx: A condition in which the fallopian tubes become filled with fluid, leading to inflammation and scarring.
2. Salpingitis: An inflammation of the fallopian tubes, often caused by bacterial or fungal infections.
3. Tubal pregnancy: A rare condition in which a fertilized egg implants in the fallopian tube instead of the uterus.
4. Ectopic pregnancy: A condition in which a fertilized egg implants outside of the uterus, often in the fallopian tube.
5. Pelvic inflammatory disease (PID): An infection of the reproductive organs in the pelvis, which can cause scarring and damage to the fallopian tubes.
6. Endometriosis: A condition in which tissue similar to the lining of the uterus grows outside of the uterus, often affecting the fallopian tubes.
7. Adenomyosis: A condition in which tissue similar to the lining of the uterus grows into the muscle of the uterus, often affecting the fallopian tubes.
8. Fimbrial tumors: Rare growths that can occur in the fallopian tubes, often benign but can be cancerous.
9. Mullerian duct anomalies: Congenital abnormalities of the fallopian tubes and other reproductive organs.
10. Oophoritis: Inflammation of the ovaries, which can affect the fallopian tubes.

Fallopian tube diseases can be diagnosed through a variety of tests, including hysterosalpingography (HSG), laparoscopy, and ultrasound. Treatment options vary depending on the specific condition and can include antibiotics for infections, surgery to remove blockages or scar tissue, or assisted reproductive technology such as in vitro fertilization (IVF) if the fallopian tubes are damaged or blocked.

OHSS typically occurs when too many eggs are stimulated to mature during ovulation, leading to an imbalance in hormone levels. The syndrome is more common in women who undergo IVF with high-dose fertility medications, multiple embryo transfer, or those with polycystic ovary syndrome (PCOS).

Symptoms of OHSS may include:

1. Enlarged ovaries that are painful to the touch
2. Abdominal bloating and discomfort
3. Pelvic pain
4. Nausea and vomiting
5. Diarrhea or constipation
6. Abnormal vaginal bleeding
7. Elevated hormone levels (estradiol and/or LH)

OHSS can be diagnosed through ultrasound and blood tests. Treatment options for OHSS include:

1. Cancellation of further fertility treatment until symptoms resolve
2. Medications to reduce hormone levels and inflammation
3. Ultrasound-guided aspiration of fluid from the ovaries
4. Hospitalization for monitoring and supportive care

Prevention is key, and fertility specialists take several measures to minimize the risk of OHSS, such as:

1. Monitoring hormone levels and ultrasound assessment of ovarian response during treatment
2. Adjusting medication dosages based on individual patient needs
3. Limited embryo transfer to reduce the risk of multiple pregnancies
4. Avoiding the use of high-dose stimulation protocols in women with PCOS or other risk factors

Early detection and proper management are crucial to prevent complications and ensure a successful outcome for fertility treatment. If you suspect you may have OHSS, it is essential to consult a fertility specialist immediately.

Here are some key points to consider when discussing azoospermia:

1. Causes: Azoospermia can be caused by various factors, including blockages due to surgery, injury, or infection, hormonal imbalances, anatomical abnormalities like varicocele, and chromosomal abnormalities.
2. Diagnosis: Azoospermia is typically diagnosed through semen analysis, which involves examining a semen sample under a microscope to determine the presence of sperm cells. Other tests may also be performed to identify any underlying causes, such as hormone level testing and ultrasound imaging.
3. Treatment: Treatment for azoospermia depends on the underlying cause, but may include medications to address hormonal imbalances or surgery to correct anatomical abnormalities. Assisted reproductive technologies (ART) like IVF or ICSI can also be used to help achieve pregnancy.
4. Prognosis: The prognosis for azoospermia varies depending on the underlying cause and the effectiveness of treatment. In general, the earlier the condition is diagnosed and treated, the better the prognosis.
5. Impact on fertility: Azoospermia can significantly impact fertility, as the absence of sperm in the semen makes it difficult or impossible to achieve pregnancy through natural means. However, with the help of ART, many men with azoospermia can still achieve fatherhood.
6. Psychological impact: Azoospermia can have significant psychological and emotional impacts on men and their partners, particularly if they are trying to conceive. It is important to provide support and counseling to help cope with the challenges of this condition.
7. Prevention: There is no known prevention for azoospermia, as it is often caused by underlying genetic or hormonal factors. However, identifying and addressing any underlying causes early on can improve outcomes and increase the chances of achieving pregnancy.

* Severe abdominal pain, often on one side of the abdomen
* Vaginal bleeding, which may be heavy or light
* Faintness or dizziness
* Shoulder pain or a sense of heaviness in the shoulder
* Feeling faint or lightheaded

An ectopic pregnancy occurs when a fertilized egg implants outside the uterus, usually in the fallopian tube. This can happen due to various reasons such as pelvic inflammatory disease, previous surgery, or abnormalities in the shape of the uterus or fallopian tubes. If left untreated, an ectopic pregnancy can lead to severe bleeding, organ damage, and even death.

There are several methods for diagnosing an ectopic pregnancy, including:

* Ultrasound: This test uses high-frequency sound waves to create images of the uterus and surrounding tissues. It can help identify the location of the pregnancy and detect any abnormalities.
* Blood tests: These tests can measure the levels of human chorionic gonadotropin (hCG), a hormone produced by the placenta during pregnancy. In an ectopic pregnancy, the level of hCG may be lower than expected.
* Laparoscopy: This is a minimally invasive surgical procedure that involves inserting a thin, lighted tube through a small incision in the abdomen to visualize the pelvic organs. It can help confirm the diagnosis and locate the ectopic pregnancy.

Treatment for an ectopic pregnancy usually involves medication or surgery, depending on the severity of the condition. Medications such as methotrexate can be used to dissolve the pregnancy tissue and allow it to pass out of the body. Surgery may be necessary if the pregnancy is not responding to medication or if there are any complications. In some cases, the fallopian tube may need to be removed if it is severely damaged or if there is a risk of further damage.

Preventive measures for ectopic pregnancy include:

* Using contraception: Using a reliable form of contraception can help prevent unintended pregnancies, which can reduce the risk of an ectopic pregnancy.
* Avoiding risky behaviors: Avoiding risky sexual behaviors such as unprotected sex and multiple partners can help reduce the risk of infection and other complications that can lead to an ectopic pregnancy.
* Getting regular pelvic exams: Regular pelvic exams can help detect any abnormalities or changes in the reproductive organs, which can help identify any potential problems early on.

It is important to note that while these measures can help reduce the risk of an ectopic pregnancy, they are not foolproof and there is always a risk of complications during any pregnancy. If you suspect you may be experiencing an ectopic pregnancy or have any other concerns, it is important to seek medical attention right away.

Endometriosis can cause a range of symptoms, including:

* Painful periods (dysmenorrhea)
* Heavy menstrual bleeding
* Pelvic pain or cramping
* Infertility or difficulty getting pregnant
* Abnormal bleeding or spotting
* Bowel or urinary symptoms such as constipation, diarrhea, or painful urination during menstruation

The exact cause of endometriosis is not known, but it is thought to involve a combination of genetic, hormonal, and environmental factors. Some possible causes include:

* Retrograde menstruation: The backflow of endometrial tissue through the fallopian tubes into the pelvic cavity during menstruation
* Coelomic metaplasia: The transformation of cells that line the abdominal cavity (coelom) into endometrial cells
* Immunological factors: Abnormal immune responses that lead to the growth and accumulation of endometrial cells outside of the uterus
* Hormonal factors: Fluctuations in estrogen levels, which can stimulate the growth of endometrial cells
* Genetic factors: Inherited traits that increase the risk of developing endometriosis

There are several risk factors for developing endometriosis, including:

* Family history: A woman's risk increases if she has a mother, sister, or daughter with endometriosis
* Early onset of menstruation: Women who start menstruating at a younger age may be more likely to develop endometriosis
* Frequent or heavy menstrual bleeding: Women who experience heavy or prolonged menstrual bleeding may be more likely to develop endometriosis
* Polycystic ovary syndrome (PCOS): Women with PCOS are at higher risk for developing endometriosis
* Obesity: Being overweight or obese may increase the risk of developing endometriosis

There is no cure for endometriosis, but there are several treatment options available to manage symptoms and improve quality of life. These may include:

* Hormonal therapies: Medications that reduce estrogen levels or block the effects of estrogen on the endometrium can help manage symptoms such as pain and heavy bleeding
* Surgery: Laparoscopic surgery can be used to remove endometrial tissue and scar tissue, and improve fertility
* Alternative therapies: Acupuncture, herbal remedies, and other alternative therapies may help manage symptoms and improve quality of life

It's important for women with endometriosis to work closely with their healthcare provider to find the best treatment plan for their individual needs. With proper diagnosis and treatment, many women with endometriosis can go on to lead fulfilling lives.

There are several types of aneuploidy, including:

1. Trisomy: This is the presence of an extra copy of a chromosome. For example, Down syndrome is caused by an extra copy of chromosome 21 (trisomy 21).
2. Monosomy: This is the absence of a chromosome.
3. Mosaicism: This is the presence of both normal and abnormal cells in the body.
4. Uniparental disomy: This is the presence of two copies of a chromosome from one parent, rather than one copy each from both parents.

Aneuploidy can occur due to various factors such as errors during cell division, exposure to certain chemicals or radiation, or inheritance of an abnormal number of chromosomes from one's parents. The risk of aneuploidy increases with age, especially for women over the age of 35, as their eggs are more prone to errors during meiosis (the process by which egg cells are produced).

Aneuploidy can be diagnosed through various methods such as karyotyping (examining chromosomes under a microscope), fluorescence in situ hybridization (FISH) or quantitative PCR. Treatment for aneuploidy depends on the underlying cause and the specific health problems it has caused. In some cases, treatment may involve managing symptoms, while in others, it may involve correcting the genetic abnormality itself.

In summary, aneuploidy is a condition where there is an abnormal number of chromosomes present in a cell, which can lead to various developmental and health problems. It can occur due to various factors and can be diagnosed through different methods. Treatment depends on the underlying cause and the specific health problems it has caused.

1. Irregular menstrual cycles, or amenorrhea (the absence of periods).
2. Cysts on the ovaries, which are fluid-filled sacs that can be detected by ultrasound.
3. Elevated levels of androgens (male hormones) in the body, which can cause a range of symptoms including acne, excessive hair growth, and male pattern baldness.
4. Insulin resistance, which is a condition in which the body's cells do not respond properly to insulin, leading to high blood sugar levels.

PCOS is a complex disorder, and there is no single cause. However, genetics, hormonal imbalances, and insulin resistance are thought to play a role in its development. It is estimated that 5-10% of women of childbearing age have PCOS, making it one of the most common endocrine disorders affecting women.

There are several symptoms of PCOS, including:

1. Irregular menstrual cycles or amenorrhea
2. Weight gain or obesity
3. Acne
4. Excessive hair growth on the face, chest, and back
5. Male pattern baldness
6. Infertility or difficulty getting pregnant
7. Mood changes, such as depression and anxiety
8. Sleep apnea

PCOS can be diagnosed through a combination of physical examination, medical history, and laboratory tests, including:

1. Pelvic exam: A doctor will examine the ovaries and uterus to look for cysts or other abnormalities.
2. Ultrasound: An ultrasound can be used to detect cysts on the ovaries and to evaluate the thickness of the uterine lining.
3. Hormone testing: Blood tests can be used to measure levels of androgens, estrogen, and progesterone.
4. Glucose tolerance test: This test is used to check for insulin resistance, which is a common finding in women with PCOS.
5. Laparoscopy: A small camera inserted through a small incision in the abdomen can be used to visualize the ovaries and uterus and to diagnose PCOS.

There is no cure for PCOS, but it can be managed with lifestyle changes and medication. Treatment options include:

1. Weight loss: Losing weight can improve insulin sensitivity and reduce androgen levels.
2. Hormonal birth control: Birth control pills or other hormonal contraceptives can help regulate menstrual cycles and reduce androgen levels.
3. Fertility medications: Clomiphene citrate and letrozole are commonly used to stimulate ovulation in women with PCOS.
4. Injectable fertility medications: Gonadotropins, such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH), can be used to stimulate ovulation.
5. Surgery: Laparoscopic ovarian drilling or laser surgery can improve ovulation and fertility in women with PCOS.
6. Assisted reproductive technology (ART): In vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) can be used to help women with PCOS conceive.
7. Alternative therapies: Some complementary and alternative therapies, such as acupuncture and herbal supplements, may be helpful in managing symptoms of PCOS.

It is important for women with PCOS to work closely with their healthcare provider to develop a treatment plan that meets their individual needs and goals. With appropriate treatment, many women with PCOS can improve their menstrual regularity, fertility, and overall health.

1. Ovarian cysts: These are fluid-filled sacs that form on the ovaries. They can be benign (non-cancerous) or malignant (cancerous). Common symptoms include pelvic pain, bloating, and irregular periods.
2. Polycystic ovary syndrome (PCOS): This is a hormonal disorder that affects ovulation and can cause cysts on the ovaries. Symptoms include irregular periods, acne, and excess hair growth.
3. Endometriosis: This is a condition in which tissue similar to the lining of the uterus grows outside the uterus, often on the ovaries. Symptoms include pelvic pain, heavy bleeding, and infertility.
4. Ovarian cancer: This is a type of cancer that affects the ovaries. It is rare, but can be aggressive and difficult to treat. Symptoms include abdominal pain, bloating, and vaginal bleeding.
5. Premature ovarian failure (POF): This is a condition in which the ovaries stop functioning before the age of 40. Symptoms include hot flashes, vaginal dryness, and infertility.
6. Ovarian torsion: This is a condition in which the ovary becomes twisted, cutting off blood flow. Symptoms include severe pelvic pain, nausea, and vomiting.
7. Ovarian abscess: This is an infection that forms on the ovaries. Symptoms include fever, abdominal pain, and vaginal discharge.
8. Ectopic pregnancy: This is a condition in which a fertilized egg implants outside the uterus, often on the ovaries. Symptoms include severe pelvic pain, bleeding, and fainting.
9. Ovarian cysts: These are fluid-filled sacs that form on the ovaries. They can be benign or cancerous. Symptoms include abdominal pain, bloating, and irregular periods.
10. Polycystic ovary syndrome (PCOS): This is a hormonal disorder that affects the ovaries, causing symptoms such as irregular periods, cysts on the ovaries, and excess hair growth.

It's important to note that these are just a few examples of the many possible conditions that can affect the ovaries. If you experience any persistent or severe symptoms in your pelvic area, it is important to seek medical attention to determine the cause and receive proper treatment.

Among vertebrates, external fertilization is most common in amphibians and fish. Invertebrates utilizing external fertilization ... External fertilization typically occurs in water or a moist area to facilitate the movement of sperm to the egg. The release of ... In some cases, fertilization can take place on a spawning animal's surface and when the animals are in the turbulent wake. ... Although fertilization is usually thought of as a short-term process, there is the possibility of gametes being retained on the ...

https://en.wikipedia.org/wiki/External_fertilization

This form of fertilization produces the world's largest marine habitats. Fertilization can also occur when weather carries wind ... Ocean iron fertilization is an example of a geoengineering technique. Iron fertilization attempts to encourage phytoplankton ... Ocean iron fertilization experiments - past, present, and future looking to a future Korean Iron Fertilization Experiment in ... Trials of ocean fertilization using iron sulphate added directly to the surface water from ships are described in detail in the ...

https://en.wikipedia.org/wiki/Iron_fertilization

Fertilization could trigger such blooms. Chronic fertilization could risk the creation of dead zones, such as the one in the ... Fertilization must increase that rate, but must do so on a scale beyond the natural scale. Otherwise, fertilization changes the ... Ocean iron fertilization is an example of a geoengineering technique. Iron fertilization attempts to encourage phytoplankton ... Ocean nutrient fertilization, for example iron fertilization, of the ocean could stimulate photosynthesis in phytoplankton. The ...

https://en.wikipedia.org/wiki/Ocean_fertilization

In amphibians internal fertilization evolved from external fertilization. Fertilization which takes place inside the female ... Internal fertilization, unlike its counterpart, external fertilization, brings more control to the female with reproduction. ... Fewer offspring are produced through internal fertilization in comparison to external fertilization. This is both because the ... In external fertilization a female can only choose the time in which she releases her eggs, but not when they are fertilized. ...

https://en.wikipedia.org/wiki/Internal_fertilization

Evidence of double fertilization in Gnetales, which are non-flowering seed plants, has been reported. Double fertilization was ... Double fertilization is a complex fertilization mechanism of flowering plants (angiosperms). This process involves the joining ... Fertilisation Gamete Megaspore Oosphere Ovule Pollen Berger, F. (January 2008). "Double-fertilization, from myths to reality". ... "test-tube fertilization". The female gametophyte, the megagametophyte, that participates in double fertilization in angiosperms ...

https://en.wikipedia.org/wiki/Double_fertilization

... , or Controlled Uptake Long Term Ammonium Nutrition, is a type of injection fertilization where the entire ... CULTAN fertilization, like all forms of injection fertilization, allows for a more precise application and a more uniform ... Although CULTAN fertilization is only done for nitrogen application, injection irrigation can also be used for other types of ... During CULTAN fertilization, nitrogen is applied at the first signs of nitrogen deficiency in plants. Fertilizer is more ...

https://en.wikipedia.org/wiki/CULTAN_Fertilization

Gould M (2012). Biology of Fertilization V3 : the Fertilization Response Of the Egg. Oxford: Elsevier Science. ISBN 978-0-323- ... By convention, gestational age is calculated by adding 14 days to fertilization age and vice versa. Fertilization though ... Scientists discovered the dynamics of human fertilization in the nineteenth century. The process of fertilization involves a ... In vitro fertilization (IVF) is a process by which egg cells are fertilized by sperm outside the womb, in vitro. In Antiquity, ...

https://en.wikipedia.org/wiki/Human_fertilization

The CO2 fertilization effect or carbon fertilization effect causes an increased rate of photosynthesis while limiting leaf ... 4. The CO2 fertilization effect: higher carbohydrate production and retention as biomass and seed yield CO2 fertilization ( ... The carbon fertilization effect varies depending on plant species, air and soil temperature, and availability of water and ... The amount of CO2 uptake from CO2 fertilization also depends on how forests respond to climate change, and if they are ...

https://en.wikipedia.org/wiki/CO2_fertilization_effect

... or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is ... Fertilisation in fungi. In many fungi (except chytrids), as in some protists, fertilisation is a two step process. ... In ... The cycle of fertilisation and development of new individuals is called sexual reproduction. During double fertilisation in ... Self-fertilisation can therefore result in improved colonisation ability. In some species, self-fertilisation has persisted ...

https://en.wikipedia.org/wiki/Fertilisation

Natural Cycle IVF is in vitro fertilisation (IVF) using either of the following procedures: IVF without the use any ovarian ... "ISMAAR » Osamu Kato". Natural cycle IVF Archived 2012-05-12 at the Wayback Machine at the Human Fertilisation and Embryology ... "Natural cycle in vitro fertilisation (IVF) for subfertile couples" (PDF). The Cochrane Database of Systematic Reviews. 8 (8): ... Webarchive template wayback links, In vitro fertilisation). ...

https://en.wikipedia.org/wiki/Natural_cycle_in_vitro_fertilization

While the bee orchid showed adaptation for self-fertilisation, its mechanism also enabled occasional cross-fertilisation, ... Fertilisation of Orchids,' because it shows how important are the results of cross-fertilisation which are ensured by the ... Fertilisation of Orchids. Wikisource has original text related to this article: Fertilisation of Orchids The Complete Works of ... Fertilisation of Orchids is a book by English naturalist Charles Darwin published on 15 May 1862 under the full explanatory ...

https://en.wikipedia.org/wiki/Fertilisation_of_Orchids

... (IVF) is a process of fertilisation where an egg is combined with sperm in vitro ("in glass"). The ... This allows fertilisation to take place inside the woman's body. Therefore, this variation is actually an in vivo fertilisation ... and prepared for fertilisation. An oocyte selection may be performed prior to fertilisation to select eggs that can be ... The Human Fertilisation and Embryology Authority said in September 2018 that parents who are limited to one cycle of IVF, or ...

https://en.wikipedia.org/wiki/In_vitro_fertilisation

The Wilhelm-Tietjen-Stiftung für Fertilisation Ltd. is a controversial fertility research group. Its critics have described it ... "WILHELM TIETJEN STIFTUNG FUER FERTILISATION LIMITED credit report and annual accounts from Companies House - Friday 28th ... November 2001 as a private limited company for advertising business under the name Wilhelm Tietjen Foundation for Fertilization ...

https://en.wikipedia.org/wiki/Wilhelm-Tietjen-Stiftung_für_Fertilisation

The history of in vitro fertilisation (IVF) goes back more than half a century. In 1959 the first birth in a nonhuman mammal ... Carl Wood was dubbed "the father of IVF (in vitro fertilisation)" for having pioneered the use of frozen embryos. In the US, ... In 1959, Min Chueh Chang at the Worcester Foundation, proved fertilisation in vitro was capable of proceeding to a birth of a ... The first pregnancy achieved through in vitro human fertilisation of a human oocyte was reported in The Lancet from the Monash ...

https://en.wikipedia.org/wiki/History_of_in_vitro_fertilisation

The Human Fertilisation and Embryology Authority (HFEA) is an executive non-departmental public body of the Department of ... The Human Fertilisation and Embryology Act 1990 was drafted taking the report into account.[citation needed] The 1990 Act ... "Human Fertilisation and Embryology Act 1990". www.opsi.gov.uk. "Code of Practice: 11. Donor recruitment, assessment and ... It is a statutory body that regulates and inspects all clinics in the United Kingdom providing in vitro fertilisation (IVF), ...

https://en.wikipedia.org/wiki/Human_Fertilisation_and_Embryology_Authority

... 1990 Human Fertilisation and Embryology (Deceased Fathers) Act 2003 Human Fertilisation ... Human Fertilisation and Embryology Act can refer to the following acts of the Parliament of the United Kingdom: ... which updated and revised the 1990 Act This disambiguation page lists articles associated with the title Human Fertilisation ...

https://en.wikipedia.org/wiki/Human_Fertilisation_and_Embryology_Act

Human Fertilisation and Embryology Act at the Wellcome Trust Fox, Marie (December 2009). "The human fertilisation and ... The Human Fertilisation and Embryology Act 2008 (c 22) is an Act of the Parliament of the United Kingdom. The Act constitutes a ... The Human Fertilisation and Embryology Act 2008, as originally enacted from the National Archives. Explanatory notes to the ... "Human Fertilisation and Embryology Act 2008: Department of Health". Department of Health (United Kingdom). 1 September 2009. ...

https://en.wikipedia.org/wiki/Human_Fertilisation_and_Embryology_Act_2008

... - Principal Terms Used Human Fertilisation and Embryology Act 1990 - Table of ... Human Fertilisation and Embryology Act 1990 - Abortion Human Fertilisation and Embryology Act 1990 - Section 28 Department of ... In 1990 the Human Fertilisation and Embryology Act 1990 was passed. The Human Fertilisation and Embryology Authority, HFEA, ... Human Reproductive Cloning Act 2001 Human Fertilisation and Embryology (Deceased Fathers) Act 2003 Human Fertilisation and ...

https://en.wikipedia.org/wiki/Human_Fertilisation_and_Embryology_Act_1990

The Human Fertilisation and Embryology (Deceased Fathers) Act 2003, sections 4(4) and (5) The Human Fertilisation and ... The Human Fertilisation and Embryology (Deceased Fathers) Act 2003 (c 24) is an Act of the Parliament of the United Kingdom. ... The Act amended the Human Fertilisation and Embryology Act 1990 to allow, among other things, a man to be listed in birth ... The Human Fertilisation and Embryology (Deceased Fathers) Act 2003, as amended from the National Archives. The Human ...

https://en.wikipedia.org/wiki/Human_Fertilisation_and_Embryology_(Deceased_Fathers)_Act_2003

... is a book on evolution in plants by Charles Darwin, first ... In this book Darwin examines the effects of cross and self fertilisation of plants and provides experimental evidence for a ... hypothesis stated in his famed book of 1859, Origin of Species, that "... in none [i.e. plant] [...]can self-fertilisation go ...

https://en.wikipedia.org/wiki/The_Effects_of_Cross_and_Self_Fertilisation_in_the_Vegetable_Kingdom

Fertilization is the fusion of gametes to produce a new organism. In animals, the process involves a sperm fusing with an ovum ... Depending on the animal species, the process can occur within the body of the female in internal fertilization, or outside in ... Slow block begins in the first few seconds after fertilization and is when the release of calcium causes the cortical reaction ... Chapter 7 Fertilization: Beginning a new organism. Retrieved 3 October 2020. Gilbert, Scott (2000). Developmental Biology. 6th ...

https://en.wikipedia.org/wiki/Animal_embryonic_development

... which she stores until she is ready for egg fertilization. After fertilization, and the formation of a zygote, and varying ... In animals, fertilization of the ovum by a sperm results in the formation of a diploid zygote that develops by repeated mitotic ... Internal self-fertilization may occur in some other species. One fish species does not reproduce by sexual reproduction but ... After fertilization, a zygote is formed which grows into a new sporophytic plant. The condition of having separate sporophyte ...

https://en.wikipedia.org/wiki/Sexual_reproduction

Sulfur-coated urea products can only be applied in granular form, and thus cannot be applied via liquid fertilization methods. ... These fertilizers mitigate some of the negative aspects of urea fertilization, such as fertilizer burn. The coatings release ... Labeling of fertilizer Turf management Urea-formaldehyde Christians, Nick (2004). "Fertilization". Fundamentals of Turfgrass ...

https://en.wikipedia.org/wiki/Coated_urea

... describes the ability of sperm to move properly through the female reproductive tract (internal fertilization) ... Yanagimachi, R. (1994). "Mammalian fertilization". In Knobil, E.; Neill, J. D. (eds.). The Physiology of Reproduction. New York ... or through water (external fertilization) to reach the egg. Sperm motility can also be thought of as the quality, which is a ... Fertilization. California: Academic press. p. 29. ISBN 978-0-12-311629-1.{{cite book}}: CS1 maint: multiple names: authors list ...

https://en.wikipedia.org/wiki/Sperm_motility

Cleavage prepares the zygote to become an embryo, which is from 2 weeks to 8 weeks after conception (fertilization) in humans. ... Not long after successful fertilization by sperm, the zygote undergoes many mitotic divisions, which are also non-sexual cell ... "fertilization , Steps, Process, & Facts , Britannica". www.britannica.com. Retrieved 8 April 2022. Muhr, Jeremy; Ackerman, ... Development of an organism happens through fertilization, cleavage, blastulation, gastrulation, organogenesis, and ...

https://en.wikipedia.org/wiki/Ontogeny

Integrated fish farming in China Chapter 3 POND FERTILIZATION AND FISH FEEDS. Pond Fertilization. Integrated Fish Farming in ... Chapter III Pond fertilization and fish feeds. Network of Agriculture centres in Asia, Bangkok, Thailand. 371 pp. Young, S.-S ...

https://en.wikipedia.org/wiki/Sinotaia_quadrata

and ocean iron fertilization". ETC Group. June 27, 2007. Retrieved July 2, 2022. "Huge swaths of plankton planned to fight ... "Canada's ocean fertilization flap, and its significance". Legal Planet. October 18, 2012. Retrieved April 19, 2022. "B.C. ... Haida Ocean Fertilization Press Conference - October 19, 2012, retrieved April 19, 2022 "Haida announce termination of Russ ... As of 2022, this remains by far the largest Iron fertilization operation in history. George claimed this resulted in increased ...

https://en.wikipedia.org/wiki/Russ_George

Fageria, N. K.; Filho, M.P. Barbosa; Moreira, A.; Guimarães, C. M. (2009). "Foliar Fertilization of Crop Plants". Journal of ... George Kuepper, NCAT Agriculture Specialist (2003). "Foliar Fertilization". ATTRA Publication #CT135. ...

https://en.wikipedia.org/wiki/Foliar_feeding

Lubow, Arthur (2012). "Cross-Fertilization". The Threepenny Review (128): 26-27. ISSN 0275-1410. JSTOR 41550156. "Lukas Ligeti ...

https://en.wikipedia.org/wiki/Lukas_Ligeti

Fertilization occurs internally. The egg cases become attached to kelp or the reef with tendrils. It has been suggested that ...

https://en.wikipedia.org/wiki/Swell_shark

In vitro fertilization: is it safe and repeatable? Science 201(4357):698-699, PMID: , 10.1126/science.566955. - DOI - PubMed ... Objectives: We aimed to evaluate the associations between exposure to drinking water DBPs and in vitro fertilization (IVF) ... Associations between Urinary Concentrations of Disinfection Byproducts and in Vitro Fertilization Outcomes: A Prospective ... Associations between Urinary Concentrations of Disinfection Byproducts and in Vitro Fertilization Outcomes: A Prospective ...

https://www.ncbi.nlm.nih.gov/pubmed/37671782

Fertilization means the sperm has attached to and entered the egg. ... In vitro fertilization (IVF) is the joining of a womans egg and a mans sperm in a laboratory dish. In vitro means outside the ... In vitro fertilization (IVF) is the joining of a womans egg and a mans sperm in a laboratory dish. In vitro means outside the ... In vitro fertilization. In: Gershenson DM, Lentz GM, Valea FA, Lobo RA, eds. Comprehensive Gynecology. 8th ed. Philadelphia, PA ...

https://medlineplus.gov/ency/article/007279.htm

http://www.nlm.nih.gov/medlineplus/ency/article/007279.htm

Adds additional variants of bone meal for all your fertilization needs. - Issues · TwelveIterationMods/Fertilization ...

https://github.com/TwelveIterationMods/Fertilization/issues

SEARCH RESULTS for: Inhibit Ovum Fertilization [Drug Class] (221 results) *Share : JavaScript needed for Sharing tools. ...

https://dailymed.nlm.nih.gov/dailymed/search.cfm?query=Inhibit%20Ovum%20Fertilization&searchdb=class&page=8&pagesize=20

RESEARCH INVOLVING HUMAN IN VITRO FERTILIZATION NIH GUIDE, Volume 22, Number 26, July 23, 1993 PA NUMBER: PA-93-101 P.T. 34 ... This Program Announcement, Research Involving Human In Vitro Fertilization, is related to the priority area of family planning ... o improved conditions for fertilization o improved conditions for embryo transfer o IVF outcome in different racial and ethnic ... basic and clinical research involving human in vitro fertilization (IVF), for the purpose of enhancing the treatment of certain ...

https://grants.nih.gov/grants/guide/pa-files/PA-93-101.html

WHO Scientific Group on the Biochemistry and Microbiology of the Female and Male Genital Tracts; World Health Organization (‎Organisation mondiale de la Santé, 1965)‎ ...

https://extranet.who.int/iris/restricted/handle/10665/26724/browse?authority=Fertilization&type=mesh

Effect of different avian egg yolk types on fertilization ability of cryopreserved common carp (Cyprinus carpio) spermatozoa * ... Sperm Storage and Cross-Fertilization of Spring and Autumn Spawning Herring. *J. H. S. BLAXTER1 ... BLAXTER, J. Sperm Storage and Cross-Fertilization of Spring and Autumn Spawning Herring. Nature 172, 1189-1190 (1953). https:// ...

https://www.nature.com/articles/1721189b0?error=cookies_not_supported&code=68aa84f5-d7e5-4bc3-bf97-1b4502473414

Tag: to use iron fertilization. Geo-Engineering the Climate Would Encourage Small, Exclusive Coalitions, A New Game Theory ...

https://planetsave.com/tag/to-use-iron-fertilization/

Pages in category "In vitro fertilisation". The following 42 pages are in this category, out of 42 total. This list may not ... Retrieved from "https://en.wikipedia.org/w/index.php?title=Category:In_vitro_fertilisation&oldid=858060489" ...

https://en.m.wikipedia.org/wiki/Category:In_vitro_fertilisation

Extracorporeal fertilization and embryo transfer A Trounson et al. Clin Obstet Gynaecol. 1981 Dec. ... Research in human in-vitro fertilisation and embryo transfer. Trounson A, Conti A. Trounson A, et al. Br Med J (Clin Res Ed). ... In vitro fertilization and embryo transfer in Pretoria, South Africa. Van der Merwe JV, Irsigler UM, Botes AD, de Milander C, ... Extracorporal fertilization of the human oocyte and transfer of the embryo: consideration of technics and ethics]. Lambert RD. ...

https://pubmed.ncbi.nlm.nih.gov/6459203/

Freshwater systems and ecosystem services: Challenges and chances for cross-fertilization of disciplines. *Ágnes Vári. ORCID: ... Freshwater systems and ecosystem services: Challenges and chances for cross-fertilization of disciplines ... Challenges and chances for cross-fertilization of disciplines. Ambio 51, 135-151 (2022). https://doi.org/10.1007/s13280-021- ...

https://link.springer.com/article/10.1007/s13280-021-01556-4

How In Vitro Fertilization (IVF) Works. Nadezhda Moryak/Pexels Topics Include: Fertility and Infertility Infertility ... As a result, the use of in vitro fertilization (IVF) has increased over the past 40 years and can help people dealing with ... https://www.ted.com/talks/nassim_assefi_and_brian_a_levine_how_in_vitro_fertilization_ivf_works ...

https://ourbodiesourselves.org/health-info/how-in-vitro-fertilization-ivf-works/

First Successful In Vitro Fertilization In Dogs The first puppies born by in vitro fertilization (IVF) were delivered on July ... First Puppies Born by In Vitro Fertilization. First Successful In Vitro Fertilization In Dogs The first puppies born by in ... One of two cocker spaniel-beagle mix puppies born via in vitro fertilization in the Travis lab. Dr. Travis with his dog Buck. ... To prepare sperm for fertilization, Dr. Travis and his team duplicated the environment of the female reproductive tract with a ...

https://www.vet.cornell.edu/departments-centers-and-institutes/baker-institute/baker-news/first-puppies-born-vitro-fertilization

Fertilisation, zygote, embryo, germination , How do organisms reproduce , Biology , Khan Academy. Khan Academy India - English ... Fertilisation, zygote, embryo, germination , How do organisms reproduce , Biology , Khan Academy. Khan Academy India - English ... Fertilisation, zygote, embryo, germination , How do organisms reproduce , Biology , Khan Academy. Khan Academy India - English ... Fertilisation, zygote, embryo, germination , How do organisms reproduce , Biology , Khan Academy. Khan Academy India - English ...

https://www.pearson.com/channels/biology/asset/ad1b8ac0/double-fertilization-angiosperms

How important is CO2 plant fertilisation? Why do your plants need additional CO2? How does a CO2 system work? ... The ideal CO2 fertilisation for plants in the aquarium. CO2, also called carbon dioxide, is the main nutrient for all plants. ... The Vallisneria, on the other hand, would flourish still further, were it to receive CO2 fertilisation, assuming there is ... Admittedly, even without CO2 fertilisation, some aquarists have observed their plants growing. There are several reasons for ...

https://www.jbl.de/en/areas/section/51/co2-plant-fertilisation?country=si

In vitro fertilization and embryo culture. Eight- to twelve-week-old female FVB mice were superovulated by i.p. injection of 5 ... Mice generated by in vitro fertilization exhibit vascular dysfunction and shortened life span. Emrush Rexhaj,1 Ariane Paoloni- ... Cardiometabolic differences in children born after in vitro fertilization: follow-up study. J Clin Endocrinol Metab. 2008;93(5 ... The present findings in mice suggest that in humans, attempts to shorten the time lag between fertilization and implantation ...

https://www.jci.org/articles/view/68943

Nitrogen Fertilization Guidelines for Potato Production in Florida. Lincoln Zotarelli, Tara Wade, Gary K. England, and ... A successful N-fertilization program can be achieved using water-soluble N-fertilizer sources when the proper timing and rate ... Understanding the dynamics of potato plant growth and N uptake in response to N-fertilization is the initial step to establish ... a proper guideline for N-fertilization for sustainable production. Nitrogen uptake (also known as plant N accumulation) by ...

https://edis.ifas.ufl.edu/publication/HS1429

... for the first time a litter of puppies was born entirely from in vitro fertilization. ... This made it possible to "achieve a success rate of 80-90% fertilization" said Travis. "With a combination of gene editing ... First Puppies Born by In Vitro Fertilization. Margherita Olivo December 15th 2015 ... for the first time a litter of puppies was born entirely from in vitro fertilization. ...

https://nextnature.net/magazine/story/2015/first-puppies-born-vitro-fertilization

4 percent had been conceived using in vitro fertilization ... In Vitro Fertilization. Among 200 infants and children with ... 4 percent were conceived by in vitro fertilization (IVF), according to a study published online Sept. 20 in The Journal of ...

https://consumer.healthday.com/in-vitro-fertilization-may-be-tied-to-increased-risk-of-skull-deformity-2655357013.html

Cookies help us deliver our services. By using our services, you agree to our use of cookies. ...

https://www.wikidoc.org/index.php?title=In_vitro_fertilization&action=info

... J Trop Med. 2012; ... literature review on care delivery models for diabetes and HIV/AIDS in SSA revealed potential elements for cross-fertilisation ...

https://pubmed.ncbi.nlm.nih.gov/23209477/?dopt=Abstract

On the ocean fertilization topic, I dont believe it was illegal. He apparently did it in Canadian waters and the Canadian ... Ill be getting back to Ocean Fertilization and other science-related topics in a tiny bit. In the meantime, I thought this ... In other words... I support limited, small scale ocean fertilization experiments that mimic natural phenomena by expanding the ...

https://davidbrin.blogspot.com/2012/11/ocean-fertilization-other-palliative.html?showComment=1354288606662

Norberg, O. S., Shock, C. C., Saunders, L. D., Eldredge, E. P., Brown, B., Ross, A., Hayes, P., & Rey, J. (2007). Optimizing nitrogen use and evaluating Ethephon use in waxy barley. OSU Agricultural Experiment Station - Special Report 1075. pp. 150-156. ...

https://agsci.oregonstate.edu/tags/crop-fertilization-and-care

Ocean iron fertilization: time to lift the research taboo. Climate Change Geoengineering Philosophical Perspectives, Legal ... be enhanced by means of fertilization, for example by artificially enhanced upwelling of macronutrients or by purposeful ...

https://www.ifw-kiel.de/publications/journal-article/ocean-iron-fertilization-time-to-lift-the-research-taboo/

The ash fertilization of peatlands is called remedial fertilization. According to Antti Leinonen, ash fertilization accelerates ... Forest fertilization has been advocated by, among others, Ilkka Hämälä, President and CEO of Metsä Group, in an interview with ... Nitrogen fertilization on mineral soils will also increase carbon sinks. Specialist in Silviculture Varpu Kuutti at Tapio says ... Ash fertilization does not affect forest nature greatly. According to Antti Leinonen, the use of ash will boost surface ...

https://forest.fi/article/fertilization-of-forests-to-save-carbon-sinks/

Webinar fertilization research in openground vegetables Event date: 03/08/2021 19:30:00 - 03/08/2021 21:00:00 ... combining optimal yields with less N-residue and fertilisation in the new season. PSKW gained first experiences with small ... In the last introduction speakers will talk about fertilisation in the season 2021. ...

https://northsearegion.eu/soilcom/events/webinar-fertilization-research-in-openground-vegetables/

Québec - Plan to Suspend Public Funding for in Vitro Fertilization. Fasken Reading Time 3 minute read January 13, 2015. ... Quebec, the first province and one of the only jurisdictions worldwide to fully fund in vitro fertilization ("IVF") treatments ...

https://www.fasken.com/en/knowledge/2015/01/lifesciencesbulletin-20150113

Excessive fertilization (202 kg N ha-1) resulted in fewer nifH transcripts compared to moderate fertilization (67 kg N ha-1) ... Excessive fertilization (202 kg N ha-1) resulted in fewer nifH transcripts compared to moderate fertilization (67 kg N ha-1) ... Nitrogen fertilization rate had a stronger influence on diazotroph population size and activity (determined by nifH gene and ... Nitrogen fertilization rate had a stronger influence on diazotroph population size and activity (determined by nifH gene and ...

https://www.frontiersin.org/articles/10.3389/fmicb.2021.675693/full

When the gametes fuse at fertilization, they restore the normal number of chromosomes. Conjugation, alternation of generations ... occurs at fertilization, so bringing together new combinations of alleles. Crossing-over, the exchange of pieces of chromosomes ... The two sex cells fuse during fertilization and form a diploid zygote (which has the normal number of chromosomes). ...

https://science.jrank.org/pages/6101/Sexual-Reproduction.html

In vitro fertilization (IVF) is the joining of a woman's egg and a man's sperm in a laboratory dish. (medlineplus.gov)
Fertilization means the sperm has attached to and entered the egg. (medlineplus.gov)
If the doctor thinks the chance of fertilization is low, the sperm may be directly injected into the egg. (medlineplus.gov)
To prepare sperm for fertilization, Dr. Travis and his team duplicated the environment of the female reproductive tract with a tailor-made liquid medium supplemented with magnesium, an element they tested and found to be crucial to the capacitation process. (cornell.edu)
The procedure is the culmination of many years of work in the Travis laboratory, as every step of harvesting oocytes and sperm, maturation, fertilization, storage, and transfer required testing and optimization. (cornell.edu)
We have developed models in which sperm-egg recognition is predicated on the N-terminus of ZP2 which is cleaved by ovastacin, a metalloendoprotease released from egg cortical granules following fertilization. (nih.gov)

FRIDAY, Oct. 29, 2021 (HealthDay News) -- Among infants and children with the skull deformity known as craniosynostosis, 4 percent were conceived by in vitro fertilization (IVF), according to a study published online Sept. 20 in The Journal of Craniofacial Surgery . (healthday.com)
In the last introduction speakers will talk about fertilisation in the season 2021. (northsearegion.eu)

Nitrogen fertilization on mineral soils will also increase carbon sinks. (forest.fi)
Nitrogen fertilization rate had a stronger influence on diazotroph population size and activity (determined by nifH gene and transcript abundances) and community composition (determined by nifH gene amplicon sequencing) than agricultural season or grass species. (frontiersin.org)

Experimental studies show that disinfection byproducts (DBPs) can inhibit oocyte maturation, decrease fertilization capacity, and impair embryo development, but human evidence is lacking. (nih.gov)
The results at four steps in the procedure can be analysed: the rate of oocyte collection is 85 to 90 per cent, the rate of fertilization, 80 to 90 per cent, the rate of embryo development, 50 to 70 per cent, and the pregnancy rate per laparoscopy, 4 to 13 per cent. (nih.gov)

Effect of various factors on in vitro fertilization (IVF) and embryo transfer in the human in clomiphene/hMG/hCG stimulated cycles]. (nih.gov)
Success of in vitro fertilization and embryo transfer in relation to the causes of infertility. (nih.gov)

Using the mouse as a paradigm, we study the developmental biology of gametogenesis, fertilization and pre-implantation embryogenesis. (nih.gov)
We investigate molecular mechanisms used by germ cell-specific factors to promote spermatogenesis in males and folliculogenesis in females that ensure fertilization and sustain pre-implantation development. (nih.gov)
Editorial: Challenges in fertilization and implantation success. (bvsalud.org)

The two sex cells fuse during fertilization and form a diploid zygote (which has the normal number of chromosomes). (jrank.org)

One of two cocker spaniel-beagle mix puppies born via in vitro fertilization in the Travis lab. (cornell.edu)
This made it possible to " achieve a success rate of 80-90% fertilization" said Travis. (nextnature.net)

As expected, PMCA1/PMCA3-null eggs (dKO) had a dramatically extended Ca2+ exposure at fertilization (10 times more). (nih.gov)

Recombination, which is the production of variations in gene combinations, occurs at fertilization, so bringing together new combinations of alleles . (jrank.org)
Fertilization usually occurs on its own. (nih.gov)

Understanding the dynamics of potato plant growth and N uptake in response to N-fertilization is the initial step to establish a proper guideline for N-fertilization for sustainable production. (ufl.edu)

As a result, the use of in vitro fertilization (IVF) has increased over the past 40 years and can help people dealing with infertility, single parents, and same-sex couples. (ourbodiesourselves.org)
ABSTRACT To investigate the effects of silymarin on follicular development, we enrolled 40 healthy women undergoing in vitro fertilization (IVF) due to male factor infertility in this trial. (who.int)

The first puppies born by in vitro fertilization (IVF) were delivered on July 10, 2015 at the Baker Institute for Animal Health. (cornell.edu)
But thanks to the work of researchers at Cornell University (USA), for the first time a litter of puppies was born entirely from in vitro fertilization. (nextnature.net)

Because of the tremendous need, scientists have struggled for more than 40 years to develop fertilization techniques in dogs, but the differences between canine reproduction and that of other mammals slowed progress. (cornell.edu)

3 The pregnancy rate is about the same for IVF using natural fertilization or ICSI. (nih.gov)

Subjects are small scale composting, the long term effects of compost use, combining optimal yields with less N-residue and fertilisation in the new season. (northsearegion.eu)

Excessive fertilization (202 kg N ha -1 ) resulted in fewer nifH transcripts compared to moderate fertilization (67 kg N ha -1 ) and decreased both richness and evenness of diazotrophic community, reflecting an inhibitory effect of high N application rates on soil diazotrophic community. (frontiersin.org)

Cryopreservation of germplasm for long term storage, in vitro fertilization and rederivation of lines. (nih.gov)

This Program Announcement, Research Involving Human In Vitro Fertilization, is related to the priority area of family planning. (nih.gov)

According to Antti Leinonen, ash fertilization accelerates tree growth for decades, which means the best stands to fertilize are young ones. (forest.fi)

CONTRARY BRIN: Ocean fertilization? (blogspot.com)
Ocean fertilization? (blogspot.com)
Ocean Fertilization: Right idea. (blogspot.com)

Hire pre-approved Lawn Fertilization pros in Baton Rouge, Louisiana - with exceptional references and many years of experience. (f2o.org)

Sites considered for fertilization should include a sufficient number of healthy and vital trees, whose growth can be maintained and improved with ash. (forest.fi)

Our results revealed relationships between soil diazotrophic community and associated soil properties, adding to our understanding of the response of soil diazotrophs to N fertilization and grass species in native C 4 grass systems. (frontiersin.org)

PMCAs extrude Ca2+ from the cytosol following Ca2+ release events, so I hypothesized that deleting PMCAs in oocytes would result in prolonged Ca2+ exposure at fertilization, leading to altered fertility and embryo development. (nih.gov)
Our results suggest that 10 times more Ca2+ is ‚Äútoo much‚Äù Ca2+ for embryo development and raise awareness of the importance of appropriate Ca2+ exposure at fertilization. (nih.gov)
Monospermic fertilization is essential for the onset of development. (nih.gov)

Our objective was to evaluate the impact of N fertilization rates (0, 67, and 202 kg N ha -1 ) and grass species (switchgrass [ Panicum virgatum ] and big bluestem [ Andropogon gerardii ]) on the abundance, activity, diversity, and community composition of soil diazotrophs over three agricultural seasons (grass green-up, initial harvest, and second harvest) in a field experiment in East Tennessee, United States. (frontiersin.org)

When the gametes fuse at fertilization, they restore the normal number of chromosomes. (jrank.org)

To become capable of fertilization, they undergo a maturation process within the female reproductive tract, a process called capacitation. (cornell.edu)

In an interview with the Finnish Broadcasting Company (Yle) , Markku Remes , Senior Forest Management Specialist at the Finnish Forest Centre, said that after ash fertilization, tree growth will increase by up to 50 percent in a couple of decades. (forest.fi)

Quebec, the first province and one of the only jurisdictions worldwide to fully fund in vitro fertilization (" IVF ") treatments is now scaling back. (fasken.com)

Anatomy44

Organisms24

Diseases13

Chemicals and Drugs41

Analytical, Diagnostic and Therapeutic Techniques and Equipment44

Psychiatry and Psychology4

Phenomena and Processes50

Disciplines and Occupations1

Anthropology, Education, Sociology and Social Phenomena1

Technology, Industry, Agriculture2

Humanities3

Information Science4

Named Groups3

Health Care7

Prolonged mating in prairie voles (Microtus ochrogaster) increases likelihood of ovulation and embryo number. (1/2757)

Male gametic cell-specific gene expression in flowering plants. (2/2757)

Treatment of mouse oocytes with PI-PLC releases 70-kDa (pI 5) and 35- to 45-kDa (pI 5.5) protein clusters from the egg surface and inhibits sperm-oolemma binding and fusion. (3/2757)

Mutations in FIE, a WD polycomb group gene, allow endosperm development without fertilization. (4/2757)

Activation of Xenopus eggs by proteases: possible involvement of a sperm protease in fertilization. (5/2757)

Evidence that a starfish egg Src family tyrosine kinase associates with PLC-gamma1 SH2 domains at fertilization. (6/2757)

Na+/H+ antiporter activity in hamster embryos is activated during fertilization. (7/2757)

Nucleo-cytoplasmic interactions that control nuclear envelope breakdown and entry into mitosis in the sea urchin zygote. (8/2757)

Fertilization

Fertilization in Vitro

Spermatozoa

Sperm-Ovum Interactions

Ovum

Oocytes

Embryo Transfer

Zygote

Zona Pellucida

Sperm Injections, Intracytoplasmic

Sperm Motility

Pregnancy

Sea Urchins

Pregnancy Rate

Acrosome

Cleavage Stage, Ovum

Acrosome Reaction

Fertilizers

Sperm Capacitation

Infertility, Female

Embryonic Development

Cryopreservation

Blastocyst

Ovulation Induction

Infertility, Male

Infertility

Egg Proteins

Microinjections

Embryo Implantation

Fertility

Vitelline Membrane

Embryonic and Fetal Development

Parthenogenesis

Sperm Head

Pregnancy Outcome

Semen Preservation

Oocyte Retrieval

Oogenesis

Insemination, Artificial

Follicular Fluid

Reproductive Techniques

Urochordata

Starfish

Embryo, Mammalian

Fallopian Tubes

Meiosis

Ovule

Ovarian Follicle

Menotropins

Ovulation

Chorionic Gonadotropin

Semen

Oocyte Donation

Cumulus Cells

Acrosin

Reproductive Techniques, Assisted

Embryo Culture Techniques

Sperm Count

Sperm Transport

Insemination

Echinodermata

Superovulation

In Vitro Oocyte Maturation Techniques

Ovary

Live Birth

Reproduction

Follicle Stimulating Hormone

Epididymis

Oligospermia

Pollen Tube

Micromanipulation

Pregnancy, Multiple

Fallopian Tube Diseases

Embryo, Nonmammalian

Sperm Tail

Contraception, Immunologic

Ovarian Hyperstimulation Syndrome

Blastomeres

Ejaculation

Metaphase