Origin of Amniotic Fluid Lipids: II. Abnormal Pregnancy

Amniotic fluid from pregnancies complicated by hemolytic disease of the newborn, toxemia of pregnancy, diabetes and other conditions was subjected to detailed lipid analysis and compared to fluid from normal pregnancies. No specific diagnostically useful pattern was discerned. In pregnancies with a live outcome, the content of cholesterol esters was low. In gravidas in whom intrauterine death occurred more than 2 weeks prior to the collection of fluid, free cholesterol, unesterified fatty acids and hydrocarbons were increased, resulting in an increase in total lipid. In all circumstances, the content of phospholipid and triglyceride remained unchanged. It is suggested that the free cholesterol and unesterified fatty acids found in amniotic fluid originate by placental transfer, whereas various esterified fatty acids arise in the fetus.