The effect of intrauterine devices on acquisition and clearance of human papillomavirus.
Previous studies have shown a decrease in cervical cancer associated with intrauterine device use. It has been hypothesized that intrauterine device use may alter the natural history of human papillomavirus infections, preempting development of precancerous lesions of the cervix and cervical cancer, but the effect of intrauterine devices on the natural history of human papillomavirus infection and subsequent development of cervical cancer is poorly understood.OBJECTIVE
The purpose of this study was to evaluate the association between intrauterine device use and cervical high-risk human papillomavirus acquisition and clearance.STUDY DESIGN
This is a prospective cohort study conducted from October 2000 through June 2014 among 676 sexually active young women and girls enrolled from family planning clinics in San Francisco, CA. Data were analyzed using a Cox proportional hazards model, including time-varying indicators of intrauterine device use, and adjusting for fixed and time-dependent predictor variables.RESULTS
A total of 85 women used an intrauterine device at some time during follow-up. Among 14,513 study visits, women reported intrauterine device use at 505 visits. After adjusting for potential behavioral confounders, there was no association between intrauterine device use and human papillomavirus acquisition (hazard ratio, 0.50; 95% confidence interval, 0.20-1.23; P = .13) or clearance of human papillomavirus infection (hazard ratio, 1.44; 95% confidence interval, 0.76-2.72; P = .26).CONCLUSION
Current intrauterine device use is not associated with acquisition or persistence of human papillomavirus infection. Intrauterine device use is safe among women and girls with human papillomavirus infections and at risk for human papillomavirus acquisition. Intrauterine device use may play a role further downstream in the natural history of cervical cancer by inhibiting the development of precancerous lesions of the cervix in human papillomavirus-infected women, or enhancing clearance of established precancerous lesions.