A retrospective analysis is reported of the management of 117 cases of infertility associated with Stage III and IV endometriosis. Combined medico-microsurgical treatment was selected in 75.3% of Stage III cases and in 83.3% of those on Stage IV. Medication consisted of medroxyprogesterone acetate in 26 patients and danazol in the remaining 64. Microsurgery alone was utilized in 24.7% of Stage III patients and in 16.6% of those on Stage IV. Both surgery alone and the combined therapy had a profound positive effect on subjective symptoms: dysmenorrhea, dyspareunia and pelvic pain. Following combined therapy, pregnancy was achieved in 34.4% of all women. Respective figures are 30.7% for medroxyprogesterone acetate (29.4% Stage III and 33.3% Stage IV) and 35.9% for danazol (37.7% Stage III and 27.2% Stage IV). In the group of patients treated by surgery alone, pregnancy occurred in 25.9%. Of the pregnancies in women with Stage III endometriosis, 25 were carried to term and 6 ended with a spontaneous abortion; figures for Stage IV women are 5 and 2, respectively. Second-look laparoscopy was performed in 49 of the 79 patients who failed to conceive, at 12-36 months after treatment; persistent genital pathology, to which infertility could be attributed, was found in 77.5% of them.