Pre-eclampsia is a severe stage of hypertensive disorders of pregnancy with blood pressure greater than 160/110 mmHg, combined with damage to the heart, brain, lungs and other organs, and accompanied by fetal dysplasia. As the disease worsens, some patients may develop eclampsia, which manifests as generalized convulsions and cerebrovascular accidents in severe cases. At the same time, because of the lack of blood supply to the whole body of the pregnant woman, it may lead to the lack of blood supply to the placenta, which is prone to fetal death in the uterus and is an obstetric emergency.