Hepatitis B virus infection in pregnant women and transmission to newborns

Chronic hepatitis B affects over 350 million people worldwide. India represents the second largest pool of chronic hepatitis B virus (HBV) infection in the world with an estimated 40 million infected people. Vertical transmission is known to be the leading cause of infection and perinatal infection is associated with a very high rate of chronicity (up to 90%). Hepatitis B e antigen (HBeAg) positivity indicates that replicative form of HBV may play a role in immunotolerance in utero by crossing the placenta. Up to 40% of chronically infected individuals will die prematurely from complications such as acute liver failure, cirrhosis and hepatocellular cancer. In case of HBeAg positivity and high viral load of mother, HBV immunoglobulin is preferably given along with HBV vaccination. Antiviral therapy is recommended for use in the third trimester of pregnancy to reduce the perinatal transmission of HBV, however, use of antiviral therapy should be individualized during pregnancy. Addressing perinatal transmission through the use of immunoprophylaxis can help contain the spread of HBV. Pregnant mothers with chronic hepatitis B have unique challenges and require specialized management during and after pregnancy. This review will look at the screening of pregnant women for hepatitis B, passive and active immunoprophylaxis, mechanisms of perinatal viral transmission and therapeutic considerations in pregnancy including possible teratogenicity and efficacy of medication. Other issues such as the mode of transmission and breastfeeding will be covered.