The Hepatitis B Virus vaccine is an inactivated (recombinant), noninfectious surface antigen (HBsAg) vaccine. To date, there have been no risks to the fetus from maternal vaccination reported. In addition, there has not been a syndrome of birth defects associated with hepatitis B infection of pregnant women. In addition, because the hepatitis B virus infection may result in severe disease for the mother and chronic infection/carrier status of the newborn, pregnancy is not considered a contradiction to vaccination of women. Human data regarding the administration of the Hepatitis B vaccine during pregnancy are limited. There is one report describing 25 women who received the vaccine during the first trimester, a report describing 15 women who received 3 doses at different times during gestation, and 72 Nigerian women who received the vaccine during the third trimester. No adverse pregnancy effects or congenital malformations were reported among these groups. However, this is too small of a population to confirm the safety of this medication. Thus while the initial data available is reassuring, further investigation is required to accurately determine the safety of receiving this vaccination during human pregnancy.