Chlamydia Infections: Infections with bacteria of the genus CHLAMYDIA.Chlamydia trachomatis: Type species of CHLAMYDIA causing a variety of ocular and urogenital diseases.Chlamydia: A genus of the family CHLAMYDIACEAE whose species cause a variety of diseases in vertebrates including humans, mice, and swine. Chlamydia species are gram-negative and produce glycogen. The type species is CHLAMYDIA TRACHOMATIS.Chlamydia muridarum: Species of CHLAMYDIA causing pneumonitis in mice and hamsters. These isolates formerly belonged to CHLAMYDIA TRACHOMATIS.Sexually Transmitted Diseases, Bacterial: Bacterial diseases transmitted or propagated by sexual conduct.Genital Diseases, Female: Pathological processes involving the female reproductive tract (GENITALIA, FEMALE).Chlamydophila psittaci: A genus of CHLAMYDOPHILA infecting primarily birds. It contains eight known serovars, some of which infect more than one type of host, including humans.Male Urogenital Diseases: Pathological processes of the male URINARY TRACT and the reproductive system (GENITALIA, MALE).Uterine Cervicitis: Inflammation of the UTERINE CERVIX.Female Urogenital Diseases: Pathological processes of the female URINARY TRACT and the reproductive system (GENITALIA, FEMALE).Genital Diseases, Male: Pathological processes involving the male reproductive tract (GENITALIA, MALE).Trachoma: A chronic infection of the CONJUNCTIVA and CORNEA caused by CHLAMYDIA TRACHOMATIS.Gonorrhea: Acute infectious disease characterized by primary invasion of the urogenital tract. The etiologic agent, NEISSERIA GONORRHOEAE, was isolated by Neisser in 1879.Fallopian Tubes: 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.Fallopian Tube Diseases: Diseases involving the FALLOPIAN TUBES including neoplasms (FALLOPIAN TUBE NEOPLASMS); SALPINGITIS; tubo-ovarian abscess; and blockage.Mass Screening: Organized periodic procedures performed on large groups of people for the purpose of detecting disease.Chlamydophila pneumoniae: A species of CHLAMYDOPHILA that causes acute respiratory infection, especially atypical pneumonia, in humans, horses, and koalas.Cervix Uteri: The neck portion of the UTERUS between the lower isthmus and the VAGINA forming the cervical canal.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Pregnancy Complications, Infectious: The co-occurrence of pregnancy and an INFECTION. The infection may precede or follow FERTILIZATION.Sexual Behavior: Sexual activities of humans.Chlamydophila Infections: Infections with bacteria of the genus CHLAMYDOPHILA.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.HeLa Cells: The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.Lymphogranuloma Venereum: Subacute inflammation of the inguinal lymph glands caused by certain immunotypes of CHLAMYDIA TRACHOMATIS. It is a sexually transmitted disease in the U.S. but is more widespread in developing countries. It is distinguished from granuloma venereum (see GRANULOMA INGUINALE), which is caused by Calymmatobacterium granulomatis.Psittacosis: Infection with CHLAMYDOPHILA PSITTACI (formerly Chlamydia psittaci), transmitted to humans by inhalation of dust-borne contaminated nasal secretions or excreta of infected BIRDS. This infection results in a febrile illness characterized by PNEUMONITIS and systemic manifestations.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Urethritis: Inflammation involving the URETHRA. Similar to CYSTITIS, clinical symptoms range from vague discomfort to painful urination (DYSURIA), urethral discharge, or both.Pelvic Inflammatory Disease: A spectrum of inflammation involving the female upper genital tract and the supporting tissues. It is usually caused by an ascending infection of organisms from the endocervix. Infection may be confined to the uterus (ENDOMETRITIS), the FALLOPIAN TUBES; (SALPINGITIS); the ovaries (OOPHORITIS), the supporting ligaments (PARAMETRITIS), or may involve several of the above uterine appendages. Such inflammation can lead to functional impairment and infertility.Urethra: A tube that transports URINE from the URINARY BLADDER to the outside of the body in both the sexes. It also has a reproductive function in the male by providing a passage for SPERM.