Running head : HPV and male circumcision Effect of male circumcision on high-risk human papillomavirus prevalence in young men : results of a randomized controlled trial conducted in Orange Farm ( South Africa )

Introduction A causal association links high-risk human papillomavirus (HR-HPV) and cervical cancer, which is a major public health problem. The objective of this study was to investigate the association between male circumcision (MC) and HR-HPV prevalence among young men. Methods We used data from a male circumcision trial conducted in Orange Farm (South Africa) among men aged 18 to 24. Urethral swabs were collected during a period of 262 consecutive days among participants from the intervention (circumcised) and control (uncircumcised) groups who were reporting for a scheduled follow-up visit. Swabs were analyzed using PCR. HR-HPV prevalence rate ratios (PRRs) were assessed using univariate and multivariate log-Poisson regression. Results In an intention-to-treat analysis, HR-HPV prevalences among intervention and control groups were 14.8% (94/637) and 22.3% (140/627), respectively, with a PRR of 0.66 (0.510.86) P=0.002. Controlling for propensity score and confounders (ethnic group, age, education, sexual behavior including condom use, marital status, and HIV status) had no effect on the results. Conclusions This is the first randomized controlled trial that shows a reduction in urethral HR-HPV infection following male circumcision. This finding explains why women with circumcised partners are less at risk of cervical cancer than other women.