Q. Can hepatitis B vaccine be administered during pregnancy?

A. Yes hepatitis B vaccine can be safely administered during pregnancy.

Hepatitis in pregnancy is not associated with increased abortion rate, stillbirth, or congenital malformation. However, prematurity seems to be increased if hepatitis is acquired in the last trimester. Sixty percent of pregnant women who acquire acute HB infections at or near delivery will transmit the HB virus to their offspring. Although infection is rarely symptomatic, 70 to 90% of the babies will remain chronically infected into adult life and be prone to cirrhosis and hepatocellular carcinoma. Because of such high risks and the safety and efficacy (seroconversion 90 to 100%) of HB vaccine in preventing HB infection, it is recommended that HB vaccine be given to pregnant women at high risk.
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My take: I had a mother call recently saying that she was pregnant and had started taking Hep B vaccine just before she got pregnant. Should she take the remaining doses now or wait for the pregnancy to be completed?

The answer is clearly that she should get the vaccination completed as per schedule. This is because not only is the vaccine safe & effective, but more importantly if she gets the disease during the time she is pregnant, there is a very good chance that the new born baby may remain infected for life with Hep B and may suffer from liver cancer and liver failure during life!