Endometriosis

THE PRESENCE of endometrial tissue apart from its normal location is termed "endometriosis." External endometriosis or ectopic endometrium— endometrial tissue growing elsewhere than in the uterine musculature—is a major gynecological problem, and it has been estimated that there is proved incidence of endometriosis in one of four of all women operated on for pelvic conditions. The disorder may be divided into internal and external types. In the former the islands are found in the myometrium proper, whereas in the latter they appear on the ovaries, tubes, and peritoneum. Their presence in more distant sites such as the skin of the arm and the thigh has been reported.1 The histogenesis of endometriosis, long a matter of conjecture, remains far from settled. The various theories which attempt to explain endometriosis fall largely into three categories: first, transportation of endometrial tissue from the uterus to its ectopic location either by transtubal regurgitation