Hepatitis B in Pregnancy


Hepatitis B is a global public health problem, with the highest number of hepatitis B virus (HBV) positive cases in China and India. Since the majority are asymptomatic, the disease burden is under appreciated. It is a unique challenge to manage HBV infection in pregnant women, as can have consequences to both mother and newborn. About 12 studies in the Indian subcontinent have looked specifically at the prevalence of hepatitis B surface antigen (HBsAg) positivity in the pregnant women. The prevalence rate of HBsAg positivity in pregnant women varies from 1-9% in different parts of the country.

All pregnant women should be tested for hepatitis B surface antigen (HBsAg) early in pregnancy. Pregnancy does not have a major effect on the liver disease in mothers with chronic hepatitis B, except in the context of cirrhosis but cirrhosis is relatively uncommon in young childbearing women with HBV infection. All hepatitis B positive women should be monitored closely during pregnancy and in the postpartum period for exacerbation of disease. The risk of flares in serum aminotransferases is somewhat raised during pregnancy and postpartum but deaths, fortunately, are rare. The major concern of hepatitis B in pregnancy is when the mother is envelope antigen (HBeAg) positive which significantly increases the risk of foetal transmission (70-90%). The presence of both HBsAg and HBV-DNA in the child at birth are often transitory events and do not imply transmission of the infection.

The presence of antibodies against hepatitis B e antigen or antibodies against Hepatitis B core antigen at birth or up to 2 years of age is simply due to their crossing the placenta from the mother to the foetus, and therefore is unrelated to infection. Positivity at 12 months of life of the hepatitis B surface antigen (HBsAg) or of HBV-DNA in an infant born to an infected mother indicates a chronic infection. Infection of infants born to HBsAg-positive mothers, or of children early in life confers a high risk of chronic infection (90%), but an effective and safe vaccination prevents HBV childhood infection. The World Health Organisation recommends universal vaccination of all infants and as of 2012, 183 countries have instituted universal vaccination against hepatitis B. All infants born to HBsAg-positive mothers should receive hepatitis B vaccine and hepatitis B immunoglobulin as soon as possible after birth; preferably within 12 h. Completion of HBV vaccine is important for the newborn to gain maximal protection and consists of the birth dose followed by two subsequent doses. Mode of delivery is not associated with an increased risk of transmission. Women should have their HBV DNA level checked at the start of the third trimester as vaccine prophylaxis may fail in infants born to highly viraemic mothers (HBV DNA >107 IU/ml).

HBV transmission can be prevented in this group by concurrent nucleoside analogue therapy during the third trimester. Tenofovir and Telbivudine are both category B drugs while Lamivudine is a category C drug. In view of side effects of Tenofovir on bone mineral density of the new born few groups prefer Telbivudine therapy. Subsequent discontinuation of nucleoside analogue therapy at 1–3 months postpartum for those women who do not need continued therapy is recommended. This selective strategy requires measurement of HBsAg and HBV DNA during pregnancy. Deliverymode should be decided by obstetric indications and caesareansection is not recommended for the sole indication ofreductionof vertical HBV transmission. Breastfeeding should beencouraged provided immunoprophylaxis is given at birth.

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