The evidence and medical research to support or refute circumcision in boys has not changed in the last 40 years! If you google "circumcision and STD" you will get thousands of search results and no clear science.
In 2006 a major study out of New Zealand showed circumcised men had less incidence of contracting sexually transmitted diseases than non-cut men. Score one for circumcision! Now a new study from New Zealand has been published in The Journal of Pediatrics showing there is no difference in the incidence of catching a STD. (What's with New Zealand? Is this their contribution to the world's medical knowledge?).
Another study in the United States showed circumcised men had a slightly higher incidence of STD. And yet another study showed circumcised men masturbated more, at least once a month. That one defies common sense. Kinsey proved masturbation was universal in the 1950s. Speaking of masturbation, circumcision became widespread in the 1800's when physicians pushed it as a way to stop the sin of masturbation and oral sex. Guess they misjudged that one!
"To circumcise or not" is an decision faced by most new parents and it is important to know that there isn't good scientific evidence to guide them. It is a personal, religious, cultural, emotional, irrational decision...not a scientific one.