Blood after coitus, if it is once in a while is usually caused by fissure, if it happens often, it is considered to be caused by cervical lesions. 1. Fissure: during intercourse due to the action is more intense or more rapid, resulting in male penis ligament fissure, or women’s vulva and vagina mucosa fissure, small blood vessel rupture will occur after intercourse with blood, and will be accompanied by pain and other symptoms. 2. Cervical lesions: women suffering from cervical lesions, more common is cervicitis, cervical polyps, cervical cancer and other diseases, cervical surface of the blood vessels exposed, in the coitus touch and stimulation, easy to rupture the blood vessel wall, so after coitus with blood. This symptom alone is not enough to diagnose the disease, and may be caused by other factors. It is recommended that the patient should consult a doctor in time to clarify the cause of the disease and give targeted treatment.