Hormonal contraception and the risk of suicidal behaviour: a Swedish nationwide register-based study.

OBJECTIVES: To determine whether hormonal contraceptives are associated with subsequent risks of suicidal behaviour and depression among women of reproductive age. DESIGN: Nationwide register-based study. SETTING: Swedish national population using health and death registers. Nationwide registries provided individual-level information about the use of hormonal contraception, suicidal behaviour, depression and potential confounders. PARTICIPANTS: All women in Sweden from 1 January 2006 to 31 December 2013. OUTCOMES MEASURES: Suicidal behaviour events or registered deaths due to suicide were identified through the National Patient Register and Cause of Death Register, respectively. Clinical diagnoses of depression were obtained from the patient register. Cox regression models were used to estimate HRs with 95% CIs of suicidal behaviour and depression in women using hormonal contraceptives. RESULTS: We followed more than two million women for a median of 6.8 years (12.4 million person-years in total). No increased risk was observed among women using oral contraceptives or non-oral combined oestrogen/progestin formulations. Non-oral progestin-only contraceptives were associated with an increased risk of suicidal behaviour using both population-based (HR=1.17, 95% CI 1.13 to 1.21) and within-individual (HR=1.16, 95% CI 1.11 to 1.21) analyses. Age-stratified analyses revealed that during late adolescence (age 15-18), use of oral contraceptives or non-oral combined formulations was associated with an increased risk of suicidal behaviour (range of HRs: 1.09-1.35), an effect that was not observed in adulthood. In contrast, non-oral progestin-only contraceptives were associated with an increased risk of suicidal behaviour during both late adolescence and adulthood. CONCLUSIONS: We found no overall increased risk of suicidal behaviour among women using oral contraceptives or non-oral combined formulations. However, the observed increased risk associated with hormonal contraceptive use during adolescence, as well as with non-oral progestin-only contraception-particularly gonane-containing formulations-across the entire reproductive window warrants attention and further investigation.