Potential new treatment of endometriosis: reversible inhibition of pituitary-ovarian function by chronic intranasal administration of a luteinizing hormone-releasing hormone (LH-RH) agonist.

This paper reports on the case of a 30 year old woman suffering from pelvic endometriosis, dyspareunia, and postcoital bleeding. The patient was treated for 173 days, starting on the 7th day of the cycle, with intranasal administration of 300 mcg of Buserelin, a luteinizing hormone-releasing hormone (LH-RH) agonist, every 12 hours. During the treatment period basal luteinizing hormone (LH) and estradiol (E2) levels were measured at various time intervals. Buserelin caused a marked inhibition of pituitary and ovarian function 2 weeks after inception of treatment. Basal LH levels were low, and serum E2 levels were decreased below those usually found in the early follicular phase. The hormonal inhibition lasted for the entire treatment period, and the only side effects were hot flashes. After 2 months of treatment dyspareunia and postcoital bleeding had almost disappeared; laparoscopy at the end of treatment showed a marked regression of endometrial lesions. Ovulation returned spontaneously after only 43 days of treatment, and regular menstrual cycles appeared shortly after termination of treatment. This prompt return to normal ovarian function should be particularly advantageous for patients seeking pregnancy. This study shows that LH-RH treatment could be a valuable approach for the medical treatment of endometriosis; however, this is only a preliminary report, and further investigation is needed before it can be safely stated that LH-RH agonist is an effective drug for the longterm treatment of endometriosis.