After childbirth, there is a separation of your abdominal muscles (rectus abdominis) in the midline which does not come back with delivery and is known as muscular diastasis. The skin expansion that has occurred during pregnancy
also does not come back to normal position when there is severe stretching resulting in the formation of striae. All of these defects can be addressed by a plastic surgical procedure known as abdominoplasty
or in severe cases, lipoabdominoplasty. This would correct the skin excess and also the muscular separation and give a pretty good configuration to the waistline.