There are no signs of impending placental abruption, which is usually present by the time an abnormal examination is performed. In the case of abruptio placenta, the pregnant woman may experience vaginal bleeding, abdominal pain, and uterine tenderness. If the bleeding affects the fetus, there may be abnormal fetal movement and fetal heartbeat. In some cases, the bleeding is insidious and ultrasound is needed to assist in the diagnosis. When bleeding is excessive, the pregnant woman may experience signs of shock such as nausea, vomiting, sweating, pallor, and decreased blood pressure. If there are high-risk factors for placental abruption, such as hypertensive disorders during pregnancy, abdominal trauma, prolonged bed rest, advanced maternal age, or premature rupture of membranes before full term, pregnant women should go to regular hospitals for examination in a timely manner to rule out the possibility of placental abruption when they experience abdominal pain, vaginal bleeding and other symptoms.