First, kudos to you for having the good sense to investigate this bizarre custom. Previous posters have offered a lot of information which will allow you to realise that the reasons most often given in support of circumcising an infant are pure myth.
Ask yourself what other body part you would be willing to have amputated from your son for prophylactic reasons? What about your daughter?? When framed in this context, the notion of circumcising of a newborn baby suddenly becomes totaly rediculous.
Then ask yourself, that if you did consent to have his foreskin removed, what would you say to him when, some years later, he confronts you, demanding an explanation why you did it. I asked my mother twice. I got the same answer both times, and I realised that she was the victim of some very erroneous advice. I really wish she had used a bit more common sense, but she believed what information she had. You, in contrast, will not have that excuse. Since the advent of the internet information is readily available to almost everyone.
Finaly, as others have pointed out, is this a decision that any parent can make, in good faith, on behalf of their child? Since there is no immediate health risk, the answer has to be a resounding NO. It is his penis - it has to be his choice.