I developed carpal tunnel a couple of years ago (not pregnancy related). I had it under control through various stretching exercises (shown to me by my physio and chiro) but since I got pregnant it has come back with a vengeance. The only thing that is giving me relief at night are wrist braces. Get ones that have a metal support to stop your thumbs from bending. They can be a bit annoying at first and they're not great for cuddling (!) but the absence of pain, numbness and tingling and not waking up several times a night is just wonderful.