Brown discharge after bleeding from placenta previa may be caused by bruises that have not been drained, vaginal infections, and signs of preterm labor. 1. Bruising is not drained: brown discharge after placenta praevia bleeding may be caused by stale bleeding after placenta praevia bleeding, the residual bruising is not completely drained, and it stays in the vagina for a long time, resulting in stale bleeding. 2. Vaginal infection: brown discharge after placenta praevia bleeding may also be caused by vaginal infection, such as not paying attention to changing underwear, not paying attention to washing the pubic area, use of unclean products may trigger vaginal infection. 3. Signs of preterm labor: If there is brown discharge after placenta praevia hemorrhage, there may also be signs of preterm labor, and cesarean section should be performed as soon as possible if necessary to prevent fetal hypoxia and the risk of fetal death. If the patient has brown discharge after placenta praevia hemorrhage, it is recommended to consult a doctor in time, under the guidance of the doctor, to clarify the cause of the disease and actively cooperate with the treatment.