Seeing blood again on the 15th day after abortion may be caused by uterine cavity residue, infection and other reasons. 1. Uterine cavity residue: abortion refers to the surgical termination of early pregnancy within 10 weeks by means of surgery, which should be operated by professional physicians. Generally, the vaginal bleeding is about 1 week after the operation, but when there are cases of uterine cavity residue, it will cause long vaginal bleeding, which can be clearly diagnosed by ultrasonography. 2. Infection: When there is a combination of infection after abortion, it can also cause vaginal bleeding again on the 15th day after abortion, accompanied by fever, abdominal pain, vaginal secretions with a foul odor and other symptoms, combined with clinical manifestations and ultrasound, blood test can help diagnosis, and need to comply with the doctor’s instructions to actively give anti-infection treatment. If you see blood again on the 15th day after abortion, you need to go to the hospital in time to find out the cause and treat it actively.