ObjectiveTo investigate the significance of telbivudine (LdT) in controlling hepatitis activity and blocking mother-to-infant transmission of hepatitis B virus (HBV) in women with chronic hepatitis B (CHB) during late pregnancy. MethodsA total of 116 pregnant women were enrolled. Each was positive for hepatitis B surface antigen (HBsAg), hepatitis B e-antigen (HBeAg) and hepatitis B core antibody (anti-HBc). They all also had HBV DNA levels of ≥105 copies/ml and alanine amino transferase (ALT) levels of ≥2×ULN, with or without total bilirubin (TBil) increase. They were divided into two groups based upon their personal preference, the treatment group (n=65) and control group (n=51). The patients in the treatment group were(28±2) weeks pregnant and received LdT 600 mg once daily in addition to liver-protecting and enzyme-reducing treatments, while the patients in the control group received only the standard liver-protecting and enzyme-reducing treatment. All infants delivered by the participants received both active and passive immunization after birth. The women in the two groups were compared in terms of the HBV DNA, ALT and TBIL levels before delivery and at 7 months after delivery; positive rates of HBsAg and hepatitis B surface antibody (anti-HBs) were compared in the infants in both groups at 7 months after birth. Furthermore, maternal and neonatal complications were observed. ResultsThe levels of serum HBV DNA, ALT and TBIL in the treatment group were significantly lower than those in the control group before delivery and at 7 months after delivery (P＜005). At 7 months after birth, the infants in the treatment group had a significantly lower positive rate for HBsAg (1.5% vs. 15.7%, P＜0.05) and a significantly higher anti-HBs-positive rate (95.4% vs. 78.4%, P＜0.05) compared with those in the control group. Maternal and neonatal complications occurred significantly less frequently in the treatment group than in the control group. ConclusionLdT is effective in controlling hepatitis activity in pregnant women with CHB, as it rapidly decreases HBV DNA levels and reduces mother-to-infant transmission of HBV. Its use is therefore beneficial to both mothers and infants.