I am due in march, and my hands have been numb for months!!! My ob said it is very common and will without a doubt go away after the baby is born, especially if there is not history of carpel tunnel.
With pregnancy everything swells including your arms, even if you can't see that their swollen. There are like 100 little nerves that run in the wrist, so it's easy to imagine how things can get pinched off. The root of my carpel tunnel is actually in my armpits. My ob referred me to a do (physical therapist), which I see every 2 weeks. It doesn't relieve all of my symptoms, but does make it a bit better for the short term.

What I like the best is that she cracks my back and neck which feels amazing.

What also works is sleeping with braces on my wrists, so I don't bend them in my sleep. If you are sitting in a chair, put a pillow under your elbows so your arms are a bit elevated. This promotes better circulation.

Good luck to you.