LMo, I didn't know it was called that, but I had it with two of my boys. The doc and books that I read at the time said that it's your bones adjusting to the weight of the baby. It doesn't all happen during childbirth.

With my oldest son, the farther I got into the pregnancy, the more it felt that I had a crack in my public bone and the two halves would rub. It hurt a bit, but was nothing to make a great deal about.

Your muscles are stretching, too, so soreness isn't out of the question at all. One of my DsIL, ("C") had quite a bit of bone and muscle soreness, too, with the first two.

Have you thought of taking any birth classes? My other DIL teaches them and I had them with my youngest. Right now would be a great time for you and hubby to get started. They teach you all about your body changes as well as the baby's... and a whole lot more.