Pulmonary embolism is a major cause of death in pregnant women or mothers, and pulmonary embolism is 15 times more frequent after delivery than before. During pregnancy, as the uterus becomes bigger, it compresses the veins in the abdomen, which leads to obstruction of blood return and causes varicose veins in the lower limbs and pelvis; in addition, during pregnancy, due to the effect of progesterone, the blood is in a high coagulation state (increased coagulation factors), and it is easy to form blood fast in the veins of the pelvis or lower limbs, and these clots sometimes fall apart and, with the blood circulation, reach the lungs and embolize the pulmonary arteries, causing pulmonary embolism. Postpartum, whether natural or cesarean, will trigger the mechanism of blood clotting (otherwise, postpartum bleeding will occur), and with postpartum bed rest, the chance of causing pelvic lower extremity vein embolism or pulmonary embolism increases even more. In addition, maternal pulmonary embolism is acute and difficult to predict. When maternal varicose veins in the lower extremities and painful swelling in the lower extremities or pain on both sides of the pelvis, it is important to consult an ultrasound to help diagnose whether lower extremity or pelvic vein thrombosis occurs. It is best to get out of bed in time after delivery and not to “sit” on the moon to prevent thrombosis.