<qa>  What was the effect of telbivudine given during the second and thirdIn the present study, we evaluated the effect of telbivudine given during the second and third trimesters of pregnancy to highly viremic, HBV DNA-positive mothers on maternal HBV DNA and HBeAg levels prior to delivery and the rate of vertical transmission of HBV to infants who received passive-active immunoprophylaxis. Additionally, we investigated the timing of the administration of telbivudine on reducing the risk of perinatal transmission and the safety of telbivudine during pregnancy. 