Circumcision significantly reduces the risk of contracting herpes and human papillomavirus, says a new study that adds to the growing scientific evidence that the procedure helps stem the spread of some sexually transmitted diseases.

Circumcised heterosexual men are 35% less likely to contract human papillomavirus (HPV) and 25% less likely to catch herpes than their uncircumcised counterparts, according to the study, published in this week's New England Journal of Medicine.

The...