The red discharge at 34 weeks of pregnancy is caused by placenta praevia or hypoplastic placenta and requires rest and medication to keep the fetus in labor when it is caused by preterm labor. 1. Placenta praevia or placenta praevia: when the ultrasound examination during pregnancy suggests placenta praevia or placenta praevia, vaginal bleeding without cause and painless may occur in late pregnancy, which may be manifested as red vaginal discharge, and the combination of medical history, clinical manifestations and ultrasound examination may assist in the diagnosis. It is necessary to follow the doctor’s advice to take proper rest and closely observe the vaginal bleeding, and terminate the pregnancy at the right time according to the change of the condition. 2. Preterm labor: it may cause small amount of vaginal bleeding, accompanied by abdominal pain and shortening of the cervical canal, which can be diagnosed by combining with clinical manifestations. It is necessary to follow the doctor’s instructions to reduce the amount of activity, give ritodrine and other drugs to inhibit contractions, and give dexamethasone to promote fetal lung maturation. When red discharge occurs in the 34th week of pregnancy, it is necessary to go to the hospital in order to find out the cause and treat it promptly. In addition, the specific use of the above medications needs to be under the supervision of a doctor.