Oophorectomy is the surgical removal of an ovary or ovaries. The surgery is also called ovariectomy, but this term has been traditionally used in basic science research to describe the surgical removal of ovaries in laboratory animals. Removal of the ovaries in women is the biological equivalent of castration in males; the term castration is only occasionally used in the medical literature to refer to Oophorectomy in humans. In the veterinary sciences, the complete removal of the ovaries, oviducts, uterine horns, and the uterus is called overiohysterectomy a.k.a. spaying and is a form of sterilization.
Partial Oophorectomy or ovariotomy is a term sometimes used to describe a variety of surgeries such as ovarian cyst removal or resection of parts of the ovaries. This kind of surgery is fertility-preserving, although ovarian failure may be relatively frequent. Most of the long-term risks and consequences of Oophorectomy are not or only partially present with partial Oophorectomy.
In humans, Oophorectomy is most often performed because of diseases such as ovarian cysts or cancer; as prophylaxis to reduce the chances of developing ovarian cancer or breast cancer; or in conjunction with hysterectomy (removal of the uterus).
The removal of an ovary together with the Fallopian tube is called salpingo-oophorectomy or unilateral salpingo-oophorectomy (USO). When both ovaries and both Fallopian tubes are removed, the term bilateral salpingo-oophorectomy (BSO) is used. Oophorectomy and salpingo-oophorectomy are not common forms of birth control in humans; more usual is tubal ligation, in which the Fallopian tubes are blocked but the ovaries remain intact. In many cases, surgical removal of the ovaries is performed concurrently with a hysterectomy. The formal medical name for removal of a woman's entire reproductive system (ovaries, Fallopian tubes, and uterus) is "total abdominal hysterectomy with bilateral salpingo-oophorectomy" (TAH-BSO); the more casual term for such a surgery is "ovariohysterectomy". "Hysterectomy" is removal of the uterus (from the Greek ὑστέρα hysteria "womb" and εκτομία entomic "a cutting out of") without removal of the ovaries or Fallopian tubes.