Inclusion Criteria:  Gestational age of more than 30 weeks; Had chronic hepatitis B virus (HBV) infection; HBV DNA > 200,000 IU/ml; Consecutively normal levels of alanine aminotransferase (< 40 U/L) and total bilirubin (< 17.1 μmol/L); Willing and able to provide written informed consent and adhere to the trial protocol.  Exclusion Criteria:  Previous treatment to reduce alanine aminotransferase and total bilirubin levels; Previous antiviral treatment for HBV infection (except when antiviral agents were administered for the prevention of perinatal transmission during a previous pregnancy and discontinued more than 6 months before the current pregnancy); Coinfection with hepatitis C, D, E, or human immunodeficiency virus; Previous or current evidence of hepatocellular carcinoma, cirrhosis, systemic or other organ disorders; A hemoglobin level of less than 80 g/L; A neutrophil count of less than 1.0 × 10^9/L; An albumin level of less than 30 g/L; Clinical signs of threatened miscarriage; Evidence of fetal deformity by ultrasound examination and other tests; A history of abortion, pregnancy loss, or congenital malformation in a previous pregnancy; A history of genetic disease(s), including the family member(s); Concurrent treatment with other drugs, including but not limited to nephrotoxic drugs, immune modulators, cytotoxic drugs, nonsteroidal antiinflammatory drugs, or steroids.