Association Between Human Papillomavirus Vaccination and Primary Ovarian Insufficiency in a Nationwide Cohort.

Importance: Anecdotal case reports have suggested an association between human papillomavirus (HPV) vaccination and primary ovarian insufficiency, but observational studies of HPV and primary ovarian insufficiency are rare, and their findings do not support an association. However, available studies have been limited by statistical power, and concerns about infertility after vaccination are associated with lower levels of uptake of the cancer-preventing vaccine in many countries. Objective: To evaluate the risk of primary ovarian insufficiency after quadrivalent human papillomavirus (4HPV) vaccination. Design, Setting, and Participants: This retrospective cohort study with follow-up from 2007 to 2016 used nationwide data for 996 300 Danish-born girls and women aged 11 to 34 years. Cox proportional hazards regression was used to estimate hazard ratios (HRs) of primary ovarian insufficiency diagnoses by 4HPV vaccination status with adjustment for age, calendar period, and a propensity score summarizing health care use. Data were analyzed from October 2020 to January 2021. Exposures: Receiving 4HPV vaccination compared with receiving no vaccination. Main Outcomes and Measures: The main outcome was hospital contacts for primary ovarian insufficiency, and the main outcome measures were HRs comparing rates of primary ovarian insufficiency among vaccinated and unvaccinated individuals. Results: During 6 781 166 person-years of follow-up among 996 300 girls and women aged 11 to 34 years (505 829 vaccinated individuals [50.8%] and 490 471 unvaccinated individuals [49.2%]), 144 individuals were diagnosed with primary ovarian insufficiency, including 54 individuals diagnosed after 4HPV vaccination. The median (interquartile range) age of primary ovarian insufficiency diagnosis was 26.94 (12.68) years. The adjusted HR of primary ovarian insufficiency comparing 4HPV vaccination to no vaccination was 0.96 (95% CI, 0.55-1.68). Conclusions and Relevance: This study found no association between HPV vaccination and primary ovarian insufficiency. However, given the rarity of the outcome in this study, the presence of a clinically relevant increase in rate of diagnosis cannot be excluded.