Hematoma on the placenta in the sixth month of pregnancy is more serious. Placental hematoma may lead to placental abruption, and auxiliary examination should be carried out when symptoms such as vaginal bleeding and abdominal pain occur. Placental abruption is the partial or total detachment of the normally positioned placenta from the uterine wall after 20 weeks of gestation before the delivery of the fetus, which is life-threatening to both mother and child in severe cases. When a placental hematoma is formed, it is asymptomatic or mildly symptomatic if the area of the abruption is small and the bleeding stops with blood clotting. When the bleeding cannot be stopped and a large hematoma forms, the blood can wash away the edge of the placenta and the fetal membranes from the uterine wall, and this is a dominant abruption. If the edge of the placenta is not detached, the blood can accumulate between the placenta and the uterine wall. When the bleeding increases dramatically, the blood can infiltrate into the myometrium, causing the muscle fibers to detach, break, and denaturation, leading to utero-placental stroke, and ultimately leading to coagulation dysfunction. Clinical symptoms of placental abruption are vaginal bleeding (mostly old, non-clotting blood), abdominal pain, accompanied by increased uterine tone and uterine tenderness. When placenta previa is suspected, ultrasonography can be used to make a definitive diagnosis, and electronic fetal heart rate monitoring can be used to monitor the intrauterine status of the fetus. It is recommended that a definitive diagnosis and treatment be carried out under the supervision of a doctor.