I agree with the others. I was very very lucky to have an easy pregnancy and was riding daily past my due date, but never with a group. Not only did I not want to crash and hurt the little one; I also didn't want other people to bear the burden of being part of an accident that could have deeper implications than road rash. Everyone's comfort level varies; for me, it was riding with one or two trusted people at most. Best of luck to you!