Dyspareunia, or pain during sexual intercourse, can sometimes be associated with bleeding. Bleeding during or after sex can be caused by a variety of factors, including: Infections: Certain infections, such as a sexually transmitted infection (STI) or pelvic inflammatory disease, can cause pain during sex and bleeding. Physical conditions: Physical conditions, such as endometriosis, uterine fibroids, or cervical polyps, can cause pain during sex and bleeding. Hormonal changes: Those that occur during menopause can cause thinning of the vaginal walls and bleeding during sex. Trauma or injury: Physical trauma or damage to the vaginal or cervical area during sex can cause bleeding. Cervical or vaginal abnormalities: Abnormalities in the cervical or vaginal area, such as a cervical or vaginal tear, can cause bleeding during or after sex.