My DH got this a few months after our DD2 was born. Apparently there is a really high incidence in mothers with new babies - think it's related to angle you keep the wrist at when holding and rocking a baby. His solution was to get a steroid injection in the wrist which fixed it immediately. Not sure about getting it done while you're pregnant but I'm pretty sure you could get it done immediately after having baby. I suggest you speak to your GP about what else might be available. Let us know how you get on.