There are many reasons for abdominal pain and bleeding after intercourse, the more common ones are such as first time sex, vaginal wall polyps, cervical lesions, etc. If it is the first time to have sex, the process of sex will cause the hymen to rupture, thus causing hymenal bleeding, which will not last long and can recover on its own in 1-2 days. If it is not the first time to have sex, there are more possibilities of bleeding during sex, including bleeding from broken vaginal wall, lesions in the cervical area, menstrual bleeding, etc. If it is a large amount of bleeding, you need to exclude the possibility of menstruation, and you can check by ultrasound to know whether the irregular bleeding is caused by abnormal shedding of endometrium. The vagina and cervical area can be examined for abnormal lesions such as vaginal wall polyps, cervical erosion, cervical cancer, etc., and can be treated according to the specific test results.