Bleeding for six days after coitus has more causes, which may be related to pregnancy-related diseases, vaginitis, cervical polyps, cervical cancer and other reasons. 1. Pregnancy-related diseases: If you have had unprotected sex, the bleeding may be caused by pre-eclampsia or ectopic pregnancy, and may be accompanied by lower abdominal pain and other symptoms. 2. Vaginitis: Because the vaginal mucosa is easily damaged, if you suffer from vaginitis, it is easy to cause vaginal bleeding after coitus friction. 3. Cervical polyps: most of the cervical polyps are caused by long-term cervical inflammation stimulation, which can easily lead to contact bleeding after intercourse. 4. Cervical cancer: If the patient has cervical cancer, it may lead to irregular vaginal bleeding after intercourse. Bleeding for six days after coitus may also have other reasons, it is recommended to consult a doctor in time, complete the relevant examination, identify the specific causes, and target treatment under the guidance of a professional doctor.