Association between oral contraceptives and serious infections: A population-based cohort study

Retrospective cohort study (n=42,323 women) found higher risk for infection while using oral contraceptives, with risk ratios of 1.35 (95% CI 1.32-1.38) for Cohort 1 and 1.27 (1.24–1.31) for Cohort 2. The overall risk remained statistically significant when stratified by age.

British Journal of Clinical Pharmacology