During pregnancy, your skin undergoes various changes, many of which typically disappear after childbirth. However, in some cases, loose skin can remain. Collagen and elastin are the main components of skin, which allow it to expand during weight gain. However, once the skin is stretched, it may not be able to return to its original state. The connective tissue between the abdominal muscles can also become thinner and weaker, resulting in a bulge in the belly commonly referred to as a "mommy poo...