Sudden bright red discharge after 20 days of labor may be caused by infection in the uterine cavity, retained placenta or fetal membranes, and poor uterine recuperation, etc. The condition can be improved by general treatment, medication, and surgical treatment. 1. Uterine cavity infection: patients should pay attention to rest, can take a semi-sitting position to facilitate the drainage of bad dew, so that the inflammation is confined to the pelvis. Ampicillin, cefixime, clindamycin and other drugs can be used under the guidance of the doctor for anti-infection treatment, in order to avoid the adverse effects of drugs on the baby, breastfeeding can be suspended during the drug treatment. Surgery can be considered if the infection is serious. 2. Placenta or fetal membrane residue: under the guidance of the doctor, the use of drugs such as hysteronin for conservative treatment, to promote uterine contraction to expel the foreign body. For patients who are not well treated with medication or whose bleeding continues to worsen, surgical debridement can be performed. 3. Poor uterine regeneration: For patients with poor uterine regeneration that causes sudden bright red discharge, they can follow the doctor’s instructions to use hysterotonin, or proprietary Chinese medicines, such as motherwort granules, etc., to promote the excretion of the discharge. Patients with severe bleeding may seek medical examination and then undergo targeted surgical treatment. It is recommended to strictly follow the doctor’s instructions, actively cooperate with the doctor’s treatment, pay attention to personal hygiene in life, keep the perineum local clean, change sanitary napkins, change underwear, etc., and pay attention to monitoring the condition, if there is any abnormality, consult the doctor in a timely manner.