If it is not the first time to have intercourse but there is vaginal bleeding, the following reasons are common in clinical practice: Firstly, the hymen may not be completely fractured during the first intercourse, and then the hymen may be fractured in another place during the second intercourse, which may also cause vaginal bleeding. Secondly, it is caused by inflammation of the vagina. Since the vagina has inflammation of the mucous membrane, the local area will be congested and edematous, so friction during intercourse will lead to breakage of the skin and mucous membrane, which will cause bleeding in clinical practice. Thirdly, it may also happen to bleed during ovulation, so after intercourse, there is also vaginal bleeding. Fourth, caused by other cervical diseases, such as chronic inflammation of the cervix, cervical polyps or local cancer of the cervix, can cause bleeding during intercourse, and further examination is recommended.