[Role of oral contraceptives in preventing endometriosis-related pain progression]

Objective: To analyze the effect of oral contraceptives on dysmenorrhea in patients with endometriosis. Methods: We designed dysmenorrhea and chronic pelvic pain questionnaire.From February 2014 to February 2016 in the Gynecological Department of Peking University Third Hospital, patients suffered dysmenorrhea with or without endometriosis or adenomyosis were included.According to their own willingness, patients were divided into the research group and the control group.The research group periodically took oral contraceptives (Diane-35 or Yasmin), while the control group received no treatment.They were followed-up about dysmenorrhea every six months, and the total follow-up time was one and a half year. Results: The dysmenorrhea VAS scores of patients in research group after taking oral contraceptives for six or twelve months were significantly lower than that in baseline (VAS 4 vs 5 vs 7). The dysmenorrhea VAS scores increased after quitting medication, but remained still lower than baseline (VAS 6.5 vs 7). However, the dysmenorrhea VAS scores of patients in control group remained unchanged (VAS 6 vs 6). Patients who took pills for more than one year experienced the same severity of dysmenorrhea after six months' or one year's medication (VAS 2 vs 2), and they suffered slowly aggravating recurrent dysmenorrhea, while those who quitted after six months' medication suffered quickly recurrent dysmenorrhea.The relieving rate of dysmenorrhea in research group was significantly higher than that in control group (79.7% vs 8.2%), and the relieving rate in patients with severe pain was significantly higher than that with mild or moderate pain (87.0% vs 66.6 % vs 77.1%). The relieving rate in patients without lesions was significantly higher than patients with adenomyosis (92.6% vs 59.1%). Conclusions: Endometriosis is a progressing disease. Longterm medication of oral contraceptives can relieve the dysmenorrhea pain.The extent of pain relief was not connected with the length of medication.Dysmenorrhea recurred after quitting medication, and the longer of medication, the slower pain recurred.Patients without lesions experienced higher pain relieving rate than those with adenomyosis.