I know your post is from 10 years ago and you're no longer pregnant but for any pregnant woman experiencing this problem,
Make Pitaya smoothies or dragon fruit.
You will be smooth and you will have iron for yourself and the baby and antioxidants.
Pitaya also known as dragon fruit smoothie packets which I buy from the health food store has kept me smooth and regular.
2 organic pitaya frozen packets
1/2 cup organic raspberry and a little water or coconut water in the nutribullet or blender
drink it everyday, no pregnancy constipation.