Need a simple explaination for this. what is a rectal seal ?

A Rectocoele: Is found in women where the muscles between the rectum and vagina are thinned out and weak usually due to multiple vaginal deliveries, prolonged labor, large babies. When you strain to have a bm the rectum will bulge into the vagina and may even prolapse out the vagina. Sometime stool will trap in the bulge and you have trouble having a bm without manually pushing the stool back from the vagina.