Peng S, et al. - Among hepatitis B surface antigen–positive pregnant women with diverse viral load who delivered from June 2012 to December 2016 at Wuhan Medical Care Center for Women and Children, Wuhan, China, researchers identified the potential risk factors of hepatitis B virus (HBV) intrauterine transmission and predict the incidence of HBV intrauterine transmission. They observed that all intrauterine transmission infants were born to hepatitis B e antigen–positive mothers who had serum HBV DNA levels >7 log₁₀ copies/mL. Intrauterine transmission predictive rates were 0.06%, 0.50%, 2,81%, 8.89% in infants with maternal HBV DNA levels of 10⁵, 10⁶, 10⁷, 10⁸ copies/mL, respectively. Data confirmed the ability to predict intrauterine HBV transmission by increasing maternal viral load. In comparison to the cesarean section, vaginal delivery increased the risk of HBV transmission in infants.