Clinical Significance of Hepatitis B Surface Antigen in Cord Blood of Hepatitis B e-Antigen-Negative Chronic Hepatitis B Virus-Infected Mothers

Vertical transmission of hepatitis B virus (HBV) infection during the perinatal period is the major cause of HBV transmission. The aim of our study was to evaluate the serological and virological profiles of HBV infection in cord blood samples obtained from HBeAg-negative chronic HBV-infected women, at delivery, and to investigate their relationship with the clinical outcome (possible transmission of HBV) in neonates receiving the currently approved passive-active immunoprophylaxis schedule. Sixteen women (32%) exhibited HBsAg positivity in the cord blood but HBV-DNA has not been detected in any of the 50 cord blood samples evaluated. We conclude that HBsAg can be transferred through the placental barrier, as with other proteins, in about one third of HBeAg-negative chronic HBV-infected pregnant women, irrespective of the maternal viral load, the mode of delivery or the placenta HBV pathology. The clinical impact of this phenomenon on the intrauterine-transplacental or perinatal transmission of HBV infection and/or passive-active immunoprophylaxis failure does not seem to be important.