http://mobilis-physiotherapy.blogspot.com/2008/10/separated-rectus-abdominis-diastasis.html
The above is a website that was authored by a physical therapist.
It sounds like you are describing diastasis recti.I don't know about the authorship of the one below, but take a look at it.
http://www.befitmom.com/abdominal_separation.html
Jay
