Occurrence of menses or pregnancy after cessation of a continuous oral contraceptive

ObjectiveTo evaluate the time to return to spontaneous menses in women after 1 year of daily continuous levonorgestrel (LNG) 90 μg/ethinyl E2 (EE) 20 μg.DesignObservational study.SettingGynecologic and primary care practices.Patient(s)Women aged 18–49 years with a history of regular menstrual cycles. After participation in an open-label, continuous oral contraceptive (OC) trial for at least 6 months, participants agreed to enroll in a separate study of the return to menses or pregnancy.Intervention(s)None.Main Outcome Measure(s)Time to return to spontaneous menses or pregnancy.Result(s)The 198 subjects had a mean age of 30.4 ± 6.6 years with 72% white, 13% Hispanic, and 7% African American. The mean duration of continuous LNG/EE treatment before enrollment was 349 ± 41 days. Of the 187 (94%) subjects who completed this study, 181 returned to spontaneous menses and 4 became pregnant within 90 days after the last dose of LNG 90 μg/EE 20 μg. The median time to return to menses in the completer population was 32 days, and the incidence of spontaneous menses or pregnancy at day ≤90 was 98.9%. The duration of amenorrhea during continuous LNG/ EE use before stopping treatment was unrelated to the time to the return to menses.ConclusionsSpontaneous menses or pregnancy occurred in 98.9% of women after cessation of continuous LNG/EE.