If you tear after labor can they just leave it open instead of stiches?

Yes: Tearing of the vaginal tissues or the labia (external genitalia) is frequently the result of not having an episiotomy before delivery. It can be left without repair in certain cases as long as the rectum is intact. This could result is a very loose vaginal inlet leading to unsatisfactory relations. But a repair can always be done at a later date in time after healing of the tissue.