I don't mean to butt in here, but I think I have had the same problem, and if we're talking about the same thing, there is an exercise that you can do to help. THe vertical separation of the ab muscles that occurs during pregnancy is called diastasis, and is pretty common in pregnancy. Sometimes it corrects itself on it's own over time, and my doctor told me not to do any crunches or other "hard" ab work until the problem was less severe. This link provides a self test (although I recommend seeing a doc to be sure) to see if this is in fact what you have
http://www.bacinfo.com/popup/tips/diastasis.htm
The exercise to improve this separation is illustrated in a link at the bottom of this page
http://www.bacinfo.com/training.htm
It's called the transverse abdominal raise.
I've had 3 c-sections, and only 1 was after having to go through labor, and I know my abs are pretty much shot right now. I've had vast improvement on my actual muscle in that area, but the excess skin and the "pooch" above my scar probably won't go away without surgery.
One more thing-be careful about the ab work you do. My doc told me that the reason he held me off from doing crunches and whatnot until the separation improved is because when you have it, there is a very increased risk of hernia. Hernia's aren't always accompanied by the telltale pain, and the fact that you are swollen on one side and not the other would raise concern for me. Like I said-I hope I'm not sticking my nose in it here, and I'm not even sure that we're talking about the same thing-but I would suggest letting your doctor know about it to examine you and make sure everything's ok
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