Pregnancy involves many biochemical and physiological changes that influence the function of every organ system. In the liver, subtle changes in function are seen as a result of increasing circulating volume and venous changes. This is reflected by changes in the normal range for liver enzymes in pregnancy, compared to the non-pregnant population (Table 1).
The presence of mildly deranged liver function tests in pregnancy is common, seen in 3% of deliveries in one prospective study.4 Severe liver dysfunction is much rarer; at a major tertiary centre in London, only 54 cases of pregnancy-related liver failure were seen in an 11-year period.5
Severe liver disease in pregnancy was previously associated with high maternal mortality rates (up to 92% in acute fatty liver of pregnancy) but this has now fallen with advances in diagnosis, earlier identification and the development of new strategies for the management of hepatic disorders, including liver transplantation.5
It can be challenging to distinguish those conditions that have developed as a consequence of pregnancy from those that were present but not identified before pregnancy or those unrelated to pregnancy that have developed during the course of gestation.
Hepatitis A: pregnancy does not alter the course or outcome of this infection.
Hepatitis B: all pregnant women are screened for the presence of the hepatitis B surface antigen at booking. Pregnancy does not alter the course of acute or chronic hepatitis B infection, but the detection of infection has important consequences perinatally (i.e. to reduce mother-to-child transmission). Both active (vaccine administration) and passive (hepatitis B immunoglobulin administration) immunization of the
Transient postpartum derangement of liver transaminases has been observed (Table 1).1 It is important to ensure that liver function tests return to normal postpartum, with further investigation into underlying liver pathology if they remain abnormal. Symptoms of nausea, vomiting, pruritus and upper abdominal pain should raise the suspicion of liver disease Pregnancy-specific reference ranges should be used when interpreting liver function tests Consider use of acetylcysteine inPractice points
Alcohol consumption should be assessed as it is the most common cause of chronic liver disease. Jaundice in pregnancy is potentially serious and warrants urgent assessment and appropriate discussion with a specialist centre; however, jaundice in pregnancy does not axiomatically implicate one of the specific pregnancy-related liver disorders.2 A careful examination of the patient can reveal significant clues to the aetiology of the jaundice.
A history of longer than a few weeks makes a congenital cause or chronic liver disease more likely, and the history must seek risk factors such as alcohol misuse or previous liver disease. Jaundice in pregnancy is potentially serious and warrants urgent referral, although it may or may not be pregnancy related.2 Examination may reveal significant clues.
