The interpretation of liver function tests in pregnancy

Abnormal liver tests occur in 3-5% of pregnancies and show many different causes. Although alterations of liver enzymes could be a physiological phenomenon, it may also reflect potential severe liver injury, necessitating further assessment and accurate management. The work-up has to consider liver diseases specific of pregnancy and non pregnancy-related liver damage (coincidental and pre-existing to pregnancy). Pre-existing liver diseases during pregnancy are relatively uncommon, as pregnant women are generally young and healthy. Liver diseases unique to pregnancy are intrahepatic cholestasis of pregnancy, the HELLP syndrome (haemolysis, elevated liver enzymes, low platelets) and acute fatty liver of pregnancy. These disorders may result in foetal distress, severe liver damage and sometime hepatic failure; for these reasons the diagnostic work-up and treatment must be very fast. This review focuses on the management of pregnant women with altered liver function tests. Furthermore, the main liver diseases specific of pregnancy are described.