Some places specialize in pregnancy massage.
Tylenol
Warm baths (not hot)
Drink lots and lots of water
Mild exercise to keep things moving
I've noticed that my abdominal muscles are sore if I stretch, as if I completed an ab-specific work out the day before. I just make sure to keep moving and don't sit at my desk at work for too long. Inactivity contributes to the soreness.