Any active woman who exercised before and after her pregnancy could have told you this. I worked out 6x a week before I was pregnant, taught yoga, and ran 5 marathons in my 20s and early 30s. Here are the list of ways my body changed post-partum and how it still impacts me today, 2.5 years after giving birth.
1. First, I had to wait nearly 3 months before I felt my hips were stable enough to do any significant distance running (more than a quarter mile). I experimented at weeks 6,8, and 9 and my hips clearly told me no. My hips are definitely wider now than they were before which has changed my stride and they are still more flexible than they were before my pregnancy so I still feel a bit unstable on my feet from time to time. Great for hip opening poses in yoga though.
2. I had very high arches and they dropped just a bit due to my pregnancy. I now have to wear orthodics when I exercise because of the pressure the dropped arch has on my foot nerves.
4. My top of my pelvis tips forward a bit more which make my lower back naturally arch a bit more.
5. Though not directly related to pregnancy itself, 12 months of breast feeding caused me to hunch my shoulder and I became a bit more hunched backed. I've been consciously trying to alter this ever since.