After pregnancy, there will be the following situations: 1. Because the endometrium has undergone molting-like changes, the endometrium will no longer shed and there will be no more menstruation; 2. After pregnancy, the ovaries will no longer secrete estrogen and progesterone cyclically, so the endometrium will not undergo cycle-like changes, nor will it shed and there will be vaginal bleeding, and there will be no more menstruation during the whole pregnancy period, which is 280 days. There will be no more menstruation during the entire pregnancy period, which is 280 days. If vaginal bleeding occurs during pregnancy, it is an abnormal phenomenon and is commonly associated with preterm miscarriage, preterm labor, placenta abruptio or placenta accreta, which may cause vaginal bleeding during pregnancy.