I hear you all! It hasn't started yet, but in pregnancy I have lousy nights!
I always sleep more after the baby is born than before!
I too find if I do some gentle exercise during the day (30 mins on a treadmill for me), some yoga and a warm milk drink before bed helps a bit.
I think for some of us it is part of the price we pay for that gorgeous baby at the end!
Love Deb