Objective: To assess whether circumcision performed on postpubertal men affords the same level of protection from HIV-1 acquisition as circumcisions earlier in childhood.
Design: Cross-sectional study of a population-based cohort.
Setting: Rakai district, rural Uganda.
Methods: A total of 6821 men aged 15-59 years were surveyed and venous blood samples were tested for HIV-1 and syphilis. Age at circumcision was dichotomized into men who were circumcised before or at age 12 years (prepubertal) and men circumcised after age 12 years (postpubertal). Postpubertal circumcised men were also subdivided into those reporting circumcision at ages 13-20 years and > or = 21 years.
Results: HIV-1 prevalence was 14.1% in uncircumcised men, compared with 16.2% for men circumcised at age > or = 21 years, 10.0% for men circumcised at age 13-20 years, and 6.9% in men circumcised at age < or = 12 years. On bivariate analysis, lower prevalence of HIV-1 associated with prepubertal circumcision was observed in all age, education, ethnic and religious groups. Multivariate adjusted odds ratio of prevalent HIV-1 infection associated with prepubertal circumcision was 0.39 [95% confidence interval (CI), 0.29-0.53]. In the postpubertal group, the adjusted odds ratio for men circumcised at ages 13-20 years was 0.46 (95% CI, 0.28-0.77), and 0.78 (95% CI, 0.43-1.43) for men circumcised after age 20 years.
Conclusions: Prepubertal circumcision is associated with reduced HIV risk, whereas circumcision after age 20 years is not significantly protective against HIV-1 infection. Age at circumcision and reasons for circumcision need to be considered in future studies of circumcision and HIV risk.