A randomized controlled trial conducted in South Africa has produced no evidence that male circumcision protects against two of the most common sexually transmitted diseases, chlamydia and gonorrhea. However, some protective effect was noted against trichomonas vaginalis (2% vs. 3%), which is relatively uncommon or asymptomatic in males.
“This study demonstrates that male circumcision does not have a protective effect on [chlamydia] acquisition for men”, comment the investigators, adding “no evidence of a protective effect of male circumcision on [gonorrhoea] infection was found.”
Sobngwi-Tambekou, J. et al. Male circumcision and Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis: observations in the aftermath of a randomised controlled trial for HIV prevention. Sex Transm Infect (online edition), 2008.