From 1982, with the availability of hepatitis B vaccine, chronic hepatitis B infection rate and its complications have decreased dramatically. Today, transmission from an infected woman to her newborn still remains as one of the major problems about hepatitis B. Guidelines recommend quantification of hepatitis B virus (HBV) DNA in all infected pregnant women at the end of the second trimester. Mothers with high concentrations of HBV DNA (>1.000.000 copies/ml) should be considered for antiviral therapy. Since the immune system is activated after delivery, continuing this therapy during the postpartum period remains critical in highly viremic mothers.