Vaginal bleeding for more than a month after a medication abortion suggests the following four possibilities: First, residual uterine cavity. Patients who cannot completely expel the meconium after the gestational sac is expelled and it accumulates in the uterine cavity are prone to vaginal bleeding. This can be clearly diagnosed by gynecological ultrasound. Secondly, uterine cavity infection. Patients with vaginal bleeding caused by uterine infection will be accompanied by abdominal pain, swelling and discomfort, or even fever, and the discharged blood will have a fishy odor. The diagnosis can be made clearly through gynecological internal examination, blood count and ultrasound. Third, trophoblastic disease. Trophoblastic disease causes vaginal bleeding and may be accompanied by lung metastasis. Patients need a chest X-ray or CT of the lungs, as well as gynecologic ultrasound and blood chorionic gonadotropin to clarify the diagnosis. Fourth, poor uterine regeneration. Poor uterine regeneration can cause prolonged vaginal bleeding. Patients can be found to have a larger uterus during ultrasound, and the diagnosis can also be clarified by gynecological internal examination.