Medical Therapies

Medical therapy has a pivotal role in the long-term treatment of endometriosis-associated pain. Combined oral contraceptives and progestins, available for multiple routes of administration, are effective first-line therapies. Several randomized controlled trials demonstrated their efficacy in improving pain symptoms in the majority of patients; furthermore, they are well tolerated and have sustainable costs. Second-line therapy is represented by gonadotropin-releasing hormone agonists. Although these drugs are efficacious in treating persistent pain, despite the administration of first-line therapies, their long-term use is limited by the occurrence of adverse effects caused by the hypoestrogenism and, therefore, these therapies require an add-back therapy. Aromatase inhibitors significantly improve endometriosis-related pain; however, they cause frequent adverse effects that limit long-term use. Therefore, these agents should be administered only to women with symptoms refractory to other conventional therapies in the setting of clinical research. Gonadotropin-releasing hormone antagonists have recently been used for treating pain caused by endometriosis; the findings of multicentre phase III trials on elagolix are promising but non-inferiority trials are required to compare elagolix with first-line therapies.