The mucous membrane at the entrance to the vagina is torn and bleeding due to external force. It is a severe trauma to the soft tissues between the anus and external genitalia, resulting in a visible tear in the perineum due to local puffing and thinning, or even a severe tear to the anus. It can be diagnosed by clinical symptoms as well as colposcopy. I degree perineal laceration: It refers to the laceration of the perineal skin and mucosa, including the rupture of the labia and vestibular mucosa. Grade II perineal laceration: perineal skin, mucosa, and muscle laceration, but the anal sphincter is intact. Grade III perineal laceration: complete laceration of perineal skin, mucosa, perineal body, and anal sphincter, mostly accompanied by laceration of rectal wall. Timely and accurate repair and suturing of the laceration of the mucosa at the entrance of the vagina can effectively stop bleeding. The sutures should be sutured to the bottom of the laceration to avoid leaving a dead cavity and to avoid passing the sutures through the rectum, and to achieve good tissue alignment and hemostasis.