Abstract: Supine hypotensive syndrome is also called late pregnancy inferior vena cava syndrome.When pregnant women are lying in supine position in late pregnancy,the inferior vena cava in compression of increased uterus reduces returned blood volume and cardiac output and leads to lower blood pressure.Pregnant women have many syndromes,such as dizziness,nausea,chest tightness,cold sweats and pale.The above symptoms disappear or relieve immediately when women change into the lateral position.Without timely treatment,it would lead to maternal circulatory failure,maternal cardiac arrest,fetal distress,neonatal asphyxia and even death.Therefore,the clinical doctors should pay more attention to the prevention of supine hypotensive syndrome.

Key words: Spinal Anesthesia, Supine hypotensive syndrome, Cesarean section