Because pregnant women in the process of pregnancy, the enlarged uterus will lengthen the rectus abdominis muscle, so that the two rectus abdominis muscles will be separated from the position of the abdominal white line to adapt to the next pregnancy, pregnancy and postpartum rehabilitation. If the abdominal wall itself is thin, twins, fetuses are too large, amniotic fluid is too much, or the rectus abdominis still can't return to its original position six months to one year after delivery, it is called postpartum rectus abdominis separation.

Its symptoms are postpartum abdominal distension and relaxation, which can not be recovered for a long time.

Nearly 50% of postpartum pregnant women will have rectus abdominis separation. The deeper the rectus abdominis is separated, the weaker the abdominal muscles are, and the more difficult it is to restore the lower abdomen to flatness.

In addition, when the rectus abdominis is weakened, the support for the back will be reduced, which will increase the chance of back pain due to mechanical changes. At the same time, the separation of rectus abdominis is not conducive to pelvic floor repair, so it is necessary to repair rectus abdominis after delivery.