An analysis of published studies indicates that the antiviral drug tenofovir given to pregnant women in the second or third trimester can help prevent mother to child transmission of the hepatitis B virus (HBV).
Universal vaccination of newborn babies has brought transmission rates down to 10-30%. In their Alimentary Pharmacology & Therapeutics analysis of data from five controlled trials, Dr. Ji Hoon Kim and his colleagues found that the risk of maternal transmission to the baby is further reduced, down to only 3% (77% reduction of transmission), when the mother receives the antiviral drug tenofovir during pregnancy.
Chronic HBV infection affects approximately 240 million people worldwide. Without treatment, it is transmitted from mother to baby in about 90% of births, often causing liver disease as the child grows up. More than 600,000 people die annually because of HBV complications.