Primigravida with full term, complains of faintness on lying down and she feels well when turns to side or sitting position. This is due to
Increased intraabdominal pressure
IVC compression
Increased intracranial pressure
After heavy lunch
Supine hypotension syndrome : During late pregnancy,the gravid uterus produces a compression effect on the IVC when patient is in supine position . In 90% cases, this results in opening up of the collateral circulation by means of paraveebral and azygos veins. In 10 % cases, when collaterals fails to open up, the venous rReturn Ofthe hea may be seriously cuailed. This results in production of hypotension, tachycardia and syncope -Supine Hypotension Syndrome. The normal blood pressure is quickly restored by turning the patient to lateral position. Ref:Datta Obs 9e pg 49.
General obstetrics