Pregnant women are routinely screened for HBsAg as part of prenatal care. If a pregnant woman tests positive for HBsAg, she is considered to have an active HBV infection. This is important because HBV can be transmitted from mother to child during delivery. Without intervention, the risk of mother-to-child transmission is about 90% if the mother is HBeAg positive and 10-20% if she is HBeAg negative. Early identification allows for timely intervention to reduce this risk.
