obstetrics, branch of medicine concerned with the treatment of women during pregnancy, labor, childbirth (see birth), and the time after childbirth. Obstetricians work to ensure that pregnancy culminates in the delivery of a healthy baby, without impairing the health of the mother. The mother's medical history and health status are initially evaluated. Physical examination discloses the mother's uterine size and estimates the length of her pregnancy. If the obstetrician detects abnormalities, prenatal testing may need to be done on the fetus. An important modern development has been ultrasonography, which allows the obstetrician to non-invasively diagnose intra-uterine conditions. Delivery of the baby is helped by the use of a Friedman's chart, which shows the patterns of cervical dilation. The care of women during childbirth was originally in the hands of women (see midwifery), but in the 16th cent. physicians grew interested in the field. Of special importance were the invention of the delivery forceps by Peter Chamberlen in the 17th cent. and the introduction of anesthesia in the 19th cent. The adoption of antiseptic methods according to the theories of Joseph Lister and Ignaz Semmelweis reduced the incidence of infection in childbirth and made possible successful cesarean section. Obstetrics is often combined with gynecology as a medical specialty.

Medical and surgical specialty concerned with the management of pregnancy and childbirth and with the health of the female reproductive system. Obstetrics, first practiced by midwives, developed as a medical discipline in the 17th–19th centuries, adopting the use of forceps in delivery, anesthetics, and antiseptic methods. The last two made cesarean section possible. Obstetricians confirm pregnancy, diagnose ectopic pregnancy, conduct prenatal care, perform amniocentesis, deliver babies, and perform abortions. In the late 20th century a backlash against the excessive medicalization of birth led to a revival of midwifery and encouragement of natural childbirth. Gynecologists do routine pelvic exams, take samples for Pap smears, advise on and prescribe birth control, and treat reproductive system disorders (e.g., endometriosis, hormonal imbalances, problems with menstruation and menopause). They perform surgery to prevent conception (tubal ligation), repair pelvic injuries, and remove cysts and tumours from the uterus, cervix, and ovaries. Both specialties are involved in diagnosis and treatment of infertility. Seealso hysterectomy.

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