Oral contraceptive use in adolescence predicts lasting vulnerability to depression in adulthood

Background Previous evidence suggests that use of oral contraceptives (OCs), especially during adolescence, may increase women's vulnerability to depression in the short term. Here, we investigate whether women who had first used OC in adolescence show an increased prevalence of depression in the long term. Methods We examined 1,236 women in the United States National Health and Nutrition Examination Survey for whom information on depression and age at first OC use was publicly available. We compared women who reported first use of OCs in adolescence to women who had never used OCs and women who had first used OCs in adulthood on 1-year prevalence of major depressive disorder (MDD) assessed by trained interviewers. Results Compared with women who had used OCs during adolescence, women who had never used OCs were less likely to meet the criteria for MDD within the past year in adulthood [odds ratio (OR) = 0.31, 95% CI = 0.16-0.60], and so were women who only started using OCs in adulthood (OR = 0.54, 95% CI = 0.30-0.95). Third factors that have previously been proposed to explain the relationship between OC use and depression risk such as age at sexual debut, and, importantly, current OC use, did not account for the results in propensity score analyses. Conclusions We show a long-term association between adolescent OC use and depression risk in adulthood regardless of current OC use. Our findings suggest that adolescence may be a sensitive period during which OC use could increase women's risk for depression, years after first exposure.