The effective control of nucleos(t)ide analogues for patients infected with hepatitis B has significantly curbed the horizontal transmission of hepatitis B. However, the vertical transmission remains a serious threat to public health for directly increasing the burden of hepatitis B worldwide with the transmission rate up to 80 to 90% among high HBV DNA level if untreated. Currently, the effective prevention of mother-to-child transmission is credited to the implement of HBV vaccination and hepatitis B virus immunoglobin. To leave nobody behind, a growing body of evidence has been yielded to support the use of nucleos(t)ide analogues in the mothers during the late pregnancy. However, the clinical practice can be more complex. Therefore, investigators aim to assess the effectiveness of maternal antiviral therapy and different infants immunoprophylaxis strategy in the prevention of chronic hepatitis infection among children whose mothers were infected with chronic hepatitis B infection in the real world setting.

From 2011 to 2017, the investigators consecutively enrolled the pregnant women with chronic hepatitis B infection who were less than 28 weeks pregnant and not treated with nucleos(t)ide analogues during pregnancy. The investigators recommended those pregnant women with HBV DNA > 2*10^6 IU/ml to receive nucleos(t)ide analogues from 28 weeks of pregnancy to delivery. Patients who agreed the antiviral treatment would assigned to the treatment group and those who declined it were assigned to the control group with high HBV DNA level. Meanwhile, those pregnant women with HBV DNA < 2*10^6 IU/ml was assigned as the control group with low HBV DNA level. All infants would be instructed to receive hepatitis B vaccine and hepatitis B virus immunoglobulin within 24 hours after birth, defined as the standard immunoprophylaxis strategy and encouraged to receive immunoprophylaxis within 2 hours after birth, defined as the aggressive immunoprophylaxis strategy. Umbilical cord blood were collected to determine the HBV serological markers and HBV DNA level. Children were followed every three to four years until December 2018.

Inclusion Criteria:

• HBsAg positive women who were less than 28 weeks pregnant and underwent routine testing for HBV at the Department of Infectious Diseases of Taicang First People's Hospital at least twice during pregnancy

Exclusion Criteria:

• women treated with antiviral drugs during pregnancy.
• drug hypersensitivity;
• abnormal renal laboratory results;
• coinfection with human immunodeficiency virus or other human hepatitis viruses.

In the real-world setting, we recruited consecutively HBsAg positive women who were less than 28 weeks pregnant and underwent routine testing for HBV at the Department of Infectious Diseases of Taicang First People's Hospital at least twice during pregnancy. Patients were excluded from participation if they had been treated with antiviral drugs during pregnancy. Additional exclusion criteria were drug hypersensitivity, abnormal renal laboratory results, coinfection with human immunodeficiency virus or other human hepatitis viruses.