Endometriosis is a benign disorder characterized by the presence and proliferation of endometrial tissue outside the endometrial cavity.  The clinical manifestations are variable.  Endometriosis occurs most commonly between the ages of 30 to 40 and is found incidentally at the time of surgery in approximately one fifth of all gyneocologic operations.  The fertility rate is significantly reduced in affected women.  The disorder usually involves the posterior cul-de-sac or the ovaries and can give rise to ovarian enlargement, although it may also involve sites distant to the pelvis (lung, umbilicus).  The most significant symptom is pelvic pain, characteristically dysmenorrheal.  However, the frequency and degree of pelvic symptomatology correlate poorly with the extent of disease.  Other symptoms include dyspareunia or pain in intercourse, pain with defecation and infertility.  The characteristic physical findings are multiple tender nodules palpable along the uterosacral ligament at the time of rectal vaginal examination, a posteriorly fixed uterus, or enlarged cystic ovaries.   Endometriosis is rarely found after the menopause.