This study is intended to retrospectively collect HBV-infected pregnant women and non-HBV-infected pregnant women who have been born in IVF in the investigators' hospital, collect pregnant women's data during pregnancy, newborn birth data, and hepatitis B virus in July after birth of newborns born to HBV-infected pregnant women. Infection, explore the impact of HBV infection on IVF outcomes and whether IVF operations increase the risk of mother-to-child transmission of HBV.

This study is a retrospective study that only retrospectively collects a variety of patient data and does not perform any treatment or examination on the patient. The research design is as follows: 1. All patients with HBV-infected pregnant women and non-HBV-infected pregnant women who had undergone IVF operation were retrospectively collected from the investigators' hospital HIS system. 2.Collecting pregnant women's data from the HIS system (including age, maternal history, liver function during pregnancy, HBV DNA in early pregnancy and before delivery, complication and complications during pregnancy, antiviral use before and during pregnancy, father HBV infection Status), neonatal birth data (including body length, weight, Apgar score, feeding status, hepatitis B vaccination, hepatitis B immunoglobulin use, HBsAg at birth and 7 months after birth, HBV DNA). 3. Statistical analysis: (1) Compare the body length, body weight, Apgar score of newborns born to pregnant women with HBV infection and non-HBV infection, and understand the effect of HBV infection on IVF outcomes. (2) Newborns born to HBV-infected pregnant women were divided into HBV DNA-negative group, low-viral group, and high-viral group according to HBV DNA status. The HBV infection status of these newborns was counted in July, and the different viral loads were tested. The impact on mother-to-child transmission of HBV. (3) When discussing whether IVF operation increases the rate of mother-to-child transmission of HBV, it is more scientific and persuasive to use HBV-infected pregnant women who have not been operated with IVF, but the incidence of twins in IVF is significantly higher than that of natural pregnancy. Further lead to premature birth, postpartum hemorrhage, cesarean section rate, etc., the weight and length of newborns are also affected, so it is difficult to match the appropriate population, so this study decided to HBV infection rate of different HBV DNA load IVF Compared with the literature, the corresponding viral load of HBV infection was compared with the rate of mother-to-child transmission of IVF pregnant women.

Inclusion Criteria:

• pregnant women who have been IVF-operated
• HBV-infected pregnant women need to be positive for HBsAg for more than half a year.

Exclusion Criteria:

• Combined with pregnancy-induced hypertension, premature rupture of membranes, prenatal bleeding and other diseases;
• history of amniocentesis during pregnancy;
• combined with other viral infections: such as HCV, HIV, CMV.

All enrolled subjects are pregnant women

All HBV-infected pregnant women who have been IVF-operated and non-HBV-infected pregnant women, HBV-infected pregnant women need to be positive for HBsAg for more than half a year.