Hi Kristen,
Welcome to the board and congrats on your new little one. I had placenta previa with my second. I spent 3 months on bedrest. Not fun. She is a happy healthy 19 year old now. So she was worth it.
Now, about your possible son. I would tell DH he has to do the research and find a MEDICAL reason to alter your newborns penis and put him through the risks of surgery. (don't worry he won't find any) It has to be a medical reason, so that leaves out the locker room and look like daddy arguments. Otherwise you will not consent to it. He may whine and cry, but he'll get over it. Also make him watch the circ video.
If he does happen to find some lame medical excuse come back here and we'll help you counter it.
As for the family, if they raise a stink, simply look them in the eye and say, "your obsession with my son's penis is really starting to creep me out." That usually takes care of it.
Good luck, Terri