One sneaky thing that can happen during pregnancy, is tension in your abdominal muscles and rib cage. As your baby is growing and your belly is expanding, sometimes your muscles tighten up in response to the new stretching sensation place on them.

If we make sure that our tissue (muscles and fascia) is flexible and mobile, we can significantly reduce discomfort during pregnancy. We also can decrease the degree of ab separation - think about it, if you have really tight muscles pulling on the middle of your belly, that will create more separation vs the muscle having normal tone.