Gonadotropin-releasing hormone analogue (goserelin) plus hormone replacement therapy for the treatment of endometriosis: a randomized controlled trial

OBJECTIVE: To determine whether treatment of endometriosis with a GnRH analogue (GnRH-a; goserelin) combined with continuous estrogen and progestogen hormone replacement therapy (HRT) would prevent the hypoestrogenic effects, including loss of bone density, while maintaining efficacy for treatment of endometriosis. DESIGN: Randomized controlled trial. PATIENTS: Fifty premenopausal women with laparoscopically diagnosed endometriosis (revised American Fertility Score for endometriosis implants equal to four or greater) and significant symptoms of dysmenorrhoea, dyspareunia, and other pelvic pain. INTERVENTION: Patients were randomized to receive either goserelin alone, 3.6 mg SC depot every 4 weeks for 24 weeks, or goserelin, 3.6 mg SC depot every 4 weeks for 24 weeks, plus HRT (25 micrograms transdermal 17 beta E2 daily and 5 mg medroxyprogesterone acetate orally daily) for 20 weeks commencing with the second goserelin injection. RESULTS: There was a significant reduction in the extent of pelvic endometriosis in both groups, with no difference between the groups. Both groups experienced an improvement in symptoms and signs, again with no difference between groups. Hypoestrogenic side effects of hot flushes and loss of libido were significantly less in the group that received HRT. The amount of bone mineral density loss was significantly less in the HRT group at the lumbar spine, although it was not prevented completely. CONCLUSION: The addition of HRT to GnRH-a for the treatment of endometriosis did not reduce the efficacy of treatment, and adverse hypoestrogenic effects were decreased, although not abolished.