I was thinking that too, CA, that there are two different issues, mom's health and baby's health, and most people put #2 way before #1. It's usually just mom and doctor who are thinking about both at the same time.

I actually have taken one bad fall during this pregnancy, but it wasn't on a bike, it was while I was doing laundry. The dogs had moved a throw rug that covers an extremely slippery patch of floor, and I didn't notice and I fell down very hard. Baby was fine, I was very sore for a week and had to drive everywhere, but man, not one person told me to stop doing laundry.

You know what is verifiably bad for unborn babies, though? Stress hormones. Right now I'm preparing to argue a case in front of the US Supreme Court, work in general is killing me, I can't sleep, we thought we were going to lose our little dog last month, my husband is taking a full course load and can't help out much around the house, and I am still working out the logistics of my career once the baby is born. Anything I can do to reduce stress -- cycling, long walks, lifting weights -- I am seeing as a net positive for this baby's health. (Not to mention mine.)