Hello Doctor - I Am A 47 Year Old Woman.

Hello Doctor - I am a 47 year old woman. when I do stomach exercises, such as crunches and sit-ups, my upper abdomen from the bottom of my sternum to my belly button bulge outward almost in the shape of an inverted V. My OBGYN told me years ago that I had a belly button hernia and I was wondering if this could have something to do with it. I'm just wondering what it could be. It's disturbing to see the muscles form that way.