You may experience swelling of your carpal tunnel during pregnancy due to the natural swelling of the body. If your symptoms are severe, you may want to try wearing a wrist brace or taking Vitamin B6 daily to relieve some of the discomfort. You should of course first discuss doing this with your doctor.
Typically, carpal tunnel symptoms will diminish after the birth of your baby, just as swelling in other parts of your body will likely resolve after delivery. If you continue to experience numbness and pain after you give birth, see your doctor.