Modifications of the native gonadotropin-releasing hormone (GnRH) decapeptide have led to longer-acting compounds with increased binding ability. Pharmacologic doses of agonists result in suppression of ovarian estradiol production to levels similar to oophorectomized patients. The resultant hypoestrogenism is associated with regression in endometrial implant size. Both subjective and objective clinical improvement have been reported. Recent studies document that a reversible state of hypogonadism is effective treatment for endometriosis.