 It is a frequent cause of low maternal blood pressure (hypotension), which can result in loss of consciousness and in extreme circumstances fetal demise.Aortocaval compression is thought to be the cause of supine hypotensive syndrome.Supine hypotensive syndrome is characterized by pallor, tachycardia, sweating, nausea, hypotension and dizziness and occurs when a pregnant woman lies on her back and resolves when she is turned on her side.