20 days and another period is not necessarily menstruation, either vaginal bleeding or menstruation, to be identified with each other and the amount of menstruation. If the bleeding is during ovulation, it is normal and does not require medication. However, if the bleeding occurs after sexual intercourse, it is recommended to check the gynecological examination of the cervix. Severe cervical erosion-like changes can also cause bleeding during intercourse, or cervical polyps can also cause contact bleeding, and in severe cases, cervical lesions. If it is an endometrial polyp or submucosal polyp, it will also bleed abnormally and can be diagnosed clearly by ultrasound exclusion. You should not have sex when bleeding, and do not eat blood-boosting drugs or food, some drugs contain blood-boosting ingredients can also cause bleeding, according to the performance and diagnosis to choose the treatment.