Endometriosis is a disease of the female pelvic mesenchyme in which tissue with epithelial and stromal characteristics of the endometrium develops in a situation other than in the uterus. The aim of this study was to evaluate the prevalence of endometriosis in premenopausal women submitted to laparoscopy and/or laparotomy for infertility, chronic pelvic pain, benign ovarian cysts and uterine myomas. The prevalence of the disease was higher in patients with infertility (30.5%), chronic pelvic (45%) and benign ovarian cysts (43%) than in patients with uterine mvomas (8.5%).