More than half a month after the cesarean section, there is still fresh blood may be caused by poor uterine recuperation, uterine cavity residue, puerperal infection, poor healing of uterine incision and other reasons. 1. Poor uterine regeneration: poor uterine contraction can lead to placental attachment surface formation of thrombus detachment, and cause uterine bleeding, manifested as bloody discharge for a long time, can be assisted in the diagnosis through gynecological examination, ultrasonography and so on. 2. Uterine cavity residual: when there are placenta and meconium tissues remaining in the uterine cavity, when the tissues are necrotic, mechanized and shed, the blood vessels at the base will be exposed and cause uterine bleeding, which will also be manifested as prolonged bloody menstrual discharge. Diagnosis can be assisted by ultrasonography, etc. 3. Puerperal infection: Inflammatory stimulation may cause poor uterine contraction and dislodgement of the thrombus formed on the adherent surface of the placenta, resulting in uterine bleeding, which may be manifested as prolonged bloody discharge with foul odor, accompanied by abdominal pain, fever and other symptoms, which can be diagnosed by combining with the medical history, ultrasonography and routine blood tests. 4. Poor healing of uterine incision: it can be caused by poor healing of uterine incision, incision infection, etc., which can also lead to prolonged bloody discharge, and ultrasound examination can help to diagnose. When there is still fresh blood more than half a month after the cesarean section, you need to go to the hospital in time to find out the cause and actively treat it.