Hepatitis B is transmitted mainly through blood, mother-to-child transmission, sexual contact, and close contact in daily life. Among them, mother-to-child transmission is the most important transmission route of hepatitis B in China. In particular, the infection rate of babies of pregnant women who are e antigen-positive and HBVDNA-positive is significantly higher. So can such a hepatitis B mother give birth to a healthy baby? This is often the most important answer that women of childbearing age who are infected with hepatitis B virus want to know. What is mother-to-child transmission? Mother-to-child transmission, also known as vertical transmission, includes the following three types: ① Intrauterine transmission Hepatitis B virus can cause intrauterine infection in the fetus through the placenta, and intrauterine infection is the main reason for the failure of hepatitis B vaccination in infants after birth. The blood, amniotic fluid and vaginal secretions of pregnant women with hepatitis B contain hepatitis B virus. During labor and delivery, damage to the skin, mucous membranes, placenta or umbilical cord of the newborn, or inhalation of amniotic fluid, blood or vaginal secretions can cause the infant to be infected with hepatitis B virus. When the infant sucks on the breast milk, the virus invades directly through the infant’s broken oral mucosa, causing the infant’s infection. There are no effective preventive measures for intrauterine infection, but the two transmission routes of intrapartum transmission and postpartum transmission can be prevented. What measures are available to interrupt mother-to-child transmission? Preconception Women of childbearing age with chronic hepatitis B who are not pregnant may be treated with interferon or nucleoside (acid) analogs if indicated for treatment, and should take reliable measures to prevent pregnancy during treatment and wait 6 months after antiviral response before considering pregnancy. Intrauterine hepatitis B infection occurs mainly in the middle and late stages of pregnancy. In addition, after 20 weeks of gestation, placental trophoblast cells have the ability to actively transfer IgG-type antibodies from the mother to the fetus, with the most pronounced transfer activity in the second 4-6 weeks of gestation. Some experts suggest that pregnant women with hepatitis B should receive 200 units of hepatitis B immunoglobulin once in each of the seven, eight and nine months of pregnancy to effectively reduce the chance of mother-to-child transmission. Some experts are skeptical of this measure to prevent mother-to-child transmission. In HBsAg-positive pregnant women, amniocentesis should be avoided and delivery should be shortened to ensure the integrity of the placenta and minimize the exposure of the newborn to maternal blood. The mode of delivery does not affect the outcome of mother-to-child transmission. Domestic and foreign experts have also found that lamivudine treatment for HBVDNA-positive women at 28 weeks of gestation can reduce the viral load to block vertical transmission from mother to child and reduce the occurrence of immune failure, while having no effect on intrauterine growth and development and the status of the fetus at birth, which is safe and effective, but there is a lack of data from large samples and long-term follow-ups to confirm this. Postconception For newborns of HBsAg-positive mothers, hepatitis B immunoglobulin should be administered as early as possible within 24 h after birth (preferably 12 h after birth), along with hepatitis B vaccination at different sites, and the second and third doses of hepatitis B vaccine at 1 and 6 months of age, respectively, to significantly improve the effectiveness of interruption of mother-to-child transmission. Alternatively, one dose of hepatitis B immunoglobulin can be administered within 12 h of birth, followed by a second dose of hepatitis B immunoglobulin 1 month later, and a simultaneous dose of hepatitis B vaccine at different sites, with the second and third doses of hepatitis B vaccine given at 1 and 6 months intervals, respectively. Newborns were allowed to receive breastfeeding from HBsAg-positive mothers after hepatitis B immunoglobulin and hepatitis B vaccine were administered within 12 h of birth. In conclusion, it is estimated that mothers with hepatitis B major without any interceptive help will transmit the hepatitis B virus to their babies during the perinatal period about 95% of the time, while mothers with regular interceptive help will have less than 5% chance of doing so. Unfortunately, however, no method of interruption can be 100% effective. What is certain is that with certain interruptions, a mother with hepatitis B can have a healthy baby.