Approximately half of the expected births to hepatitis B surface antigen (HBsAg)-positive women are identified, indicating not all HBsAg-positive pregnant women are identified and subsequently reported to perinatal hepatitis B coordinators at health departments. An important reason for under-identification of HBsAg-positive pregnant women is that test results may not include information identifying the person with an HBsAg-positive test as pregnant.
Providers or patients might believe women known to be chronically infected with HBV do not need to be tested during pregnancy. However, testing during every pregnancy helps to ensure infants are identified for postexposure management. In addition, women with Medicaid and those residing in the northeastern United States have lower screening rates.
Antiviral therapy during pregnancy for HBsAg-positive women was recently recommended by the American Association for the Study of Liver Diseases Cdc-pdf[PDF – 265 KB]External in 2016. This recommendation was based on published evidence revealing that maternal antiviral therapy during pregnancy further reduces perinatal HBV transmission. However, the threshold for recommending antiviral therapy (when maternal HBV DNA is >200,000 IU/mL) was based on limited data with few studies and needs to be better understood.