Control of endometriosis-associated pain with etonogestrel-releasing contraceptive implant and 52-mg levonorgestrel-releasing intrauterine system: randomized clinical trial

OBJECTIVE: To assess the efficacy of an etonogestrel (ENG)-releasing contraceptive implant or the 52-mg levonorgestrel-releasing intrauterine system (LNG-IUS) in the control of endometriosis-associated pelvic pain. DESIGN: Noninferiority randomized clinical trial in which women with endometriosis were assigned to use an ENG implant (experimental treatment) or an LNG-IUS (active comparator). Monthly follow-up visits were conducted up to 6 months. SETTING: University teaching hospital. PATIENT(S): One hundred three women, with endometriosis-associated chronic pelvic pain, dysmenorrhea, or both for more than 6 months. In cases of deep endometriosis, vaginal ultrasonography and magnetic resonance imaging were used as additional diagnostic tools. INTERVENTION(S): The ENG implant or the LNG-IUS were inserted within the first 5 days of the menstrual cycle. MAIN OUTCOME MEASURE(S): Daily scores of noncyclic pelvic pain and dysmenorrhea were evaluated using a daily visual analogue scale. Health-related quality of life was evaluated using the Endometriosis Health Profile-30 questionnaire at baseline and up to 6 months. Bleeding patterns were assessed daily from a menstrual calendar. RESULT(S): Both contraceptives improved significantly the mean visual analogue scale endometriosis-associated pelvic pain and dysmenorrhea, without significant differences between treatment group profiles. Health-related quality of life improved significantly in all domains of the core and modular segments of the Endometriosis Health Profile-30 questionnaire, with no difference between both treatment groups. The most common bleeding patterns at 180 days of follow-up were amenorrhea and infrequent bleeding and infrequent bleeding and spotting among ENG implant and LNG-IUS users, respectively. CONCLUSION(S): In this noninferiority study both contraceptives improved significantly pelvic pain, dysmenorrhea, and health-related quality of life in endometriosis. CLINICAL TRIAL REGISTRATION NUMBER: Clinicaltrials.gov under number NCT02480647.