Jconger, I think I've decided to go team green now. Jooooooooin us!
Cosmosis, I had a lopsided uterus with DS2. He was stuck on one side the whole time and he was almost a ten pounder carrying really low, so it pushed my back out of whack and caused me some discomfort (no issues in labor as a result of that, though, he was in a good position for delivery). I visited an osteopath during and after pregnancy and there wasn't much she could do before I gave birth because DS2 was happy just hanging out on that side of my uterus, but after the birth she realigned things and it helped with my back pain.