A small amount of brown discharge in the third trimester of pregnancy is not normal, and may be caused by preeclampsia, cervical polyps and other reasons. 1. Pre-eclampsia: can cause irregular vaginal bleeding, manifested as vaginal flow of a small amount of brown discharge, can also be accompanied by lower abdominal pain and discomfort, to comply with the doctor’s instructions to rest properly, prohibit coitus, if there is a worsening of the symptoms of the need to be given to progesterone and other drugs to protect the fetus treatment. 2. Cervical polyps: can also cause repeated irregular vaginal bleeding, gynecological examination and vaginal speculum examination can be clearly diagnosed. When repeated bleeding can increase the risk of infection, the need to follow the doctor’s orders for polyp removal, local gauze compression to stop bleeding, and sent to the pathological examination. Clinical third trimester of pregnancy with a small amount of brown discharge need to be timely to the hospital, and identify the cause, active treatment.