I have heard people complaining of this, not pregnant people, though. If you aren't finding that you get enough sleep, even with naps if possible, then try some relaxation exercises as you lie in bed. Make sure you are comfortable. Progressive relaxation: this involves concentrating on relaxing each part of your body from the toes up. Taking great care to not let the mind wander, and to relax each part and then check though. Relax your toes, relax the soles of your feet, the tops of your feet, the sides of your feet, your heals, your ankles, the back of your legs... and so forth. And every so often you check back through- are my feet still relaxed, etc. This exercise not only makes your body relax, which will be helpful even if you can't sleep, but it makes your mind focus, which may be a reason for lack of sleep. Breathe slowly and relax when you exhale.
at 12:55 PM on Jan. 1, 2010