Embryology: The study of the development of an organism during the embryonic and fetal stages of life.Histology: The study of the structure of various TISSUES of organisms on a microscopic level.Developmental Biology: The field of biology which deals with the process of the growth and differentiation of an organism.Teratology: A branch of embryology for the study of congenital malformations and developmental abnormalities.History, 19th Century: Time period from 1801 through 1900 of the common era.History, 18th Century: Time period from 1701 through 1800 of the common era.History, 20th Century: Time period from 1901 through 2000 of the common era.Laboratories, Dental: Facilities for the performance of services related to dental treatment but not done directly in the patient's mouth.Anatomy: A branch of biology dealing with the structure of organisms.Preimplantation Diagnosis: 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.Genetics: The branch of science concerned with the means and consequences of transmission and generation of the components of biological inheritance. (Stedman, 26th ed)Anatomy, Comparative: The comparative study of animal structure with regard to homologous organs or parts. (Stedman, 25th ed)Reproductive Techniques: Methods pertaining to the generation of new individuals, including techniques used in selective BREEDING, cloning (CLONING, ORGANISM), and assisted reproduction (REPRODUCTIVE TECHNIQUES, ASSISTED).Reproductive Medicine: A medical-surgical specialty concerned with the morphology, physiology, biochemistry, and pathology of reproduction in man and other animals, and on the biological, medical, and veterinary problems of fertility and lactation. It includes ovulation induction, diagnosis of infertility and recurrent pregnancy loss, and assisted reproductive technologies such as embryo transfer, in vitro fertilization, and intrafallopian transfer of zygotes. (From Infertility and Reproductive Medicine Clinics of North America, Foreword 1990; Journal of Reproduction and Fertility, Notice to Contributors, Jan 1979)History, 21st Century: Time period from 2001 through 2100 of the common era.Tracheoesophageal Fistula: Abnormal passage between the ESOPHAGUS and the TRACHEA, acquired or congenital, often associated with ESOPHAGEAL ATRESIA.Organizers, Embryonic: Cells in certain regions of an embryo that self-regulate embryonic development. These organizers have been found in dorsal and ventral poles of GASTRULA embryos, including Spemann organizer in amphibians, and Hensen node in chicken and mouse. These organizer cells communicate with each other via a network of secreted signaling proteins, such as BONE MORPHOGENETIC PROTEINS and their antagonists (chordin and noggin).Fertilization in Vitro: An assisted reproductive technique that includes the direct handling and manipulation of oocytes and sperm to achieve fertilization in vitro.Biological Evolution: The process of cumulative change over successive generations through which organisms acquire their distinguishing morphological and physiological characteristics.Embryo Research: 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.PolandSocieties, Medical: Societies whose membership is limited to physicians.