There are several reasons for bleeding during intercourse after menstruation: First, it may be because the vaginal mucosa is not fully recovered, because during menstruation, besides the endometrium, the vaginal mucosa is also shed periodically. Secondly, it may be due to gynecological inflammation, the most common ones are vaginitis and cervicitis. When there is inflammation in the vagina, the vaginal skin and mucous membrane will be indirectly attacked by inflammatory substances and bacteria, and the small arteries on the vaginal mucous membrane will be damaged, resulting in the destruction of the permeability of the blood vessel wall. The vagina itself is prone to bleeding.