Mother-to-child transmission of hepatitis B includes: perinatal transmission and subsequent close life contact transmission, of which, perinatal transmission mainly includes intrauterine infection and (obstetric) transmission during delivery. Mother-to-child transmission is the main factor of intra-family transmission of hepatitis B virus. Before the planned immunization of newborns, almost 90% of children born to mothers who are double positive for HBsAg and HBeAg are infected and become carriers of hepatitis B virus. Most of the family aggregation of hepatitis B virus is caused by mother-to-child transmission. Therefore, young women should take the initiative to get vaccinated against hepatitis B as early as possible to avoid spilling over to their offspring. Can mothers who are surface antigen positive breastfeed? Colostrum can increase the disease resistance of newborns, and breastfeeding is not only beneficial to the child, but also to the mother’s postpartum health recovery, so breastfeeding should be chosen as much as possible for those who are able to do so. However, for mothers who are positive for surface antigen, whether they can breastfeed or not has become a big problem for many mothers. Some data show that hepatitis B virus is indeed present in the milk of mothers with positive surface antigen and E antigen (double positive), such as the solid phase radioimmunoassay for HBsAG in milk, which found that 71.4% (45, 63) of colostrum was positive, suggesting that the milk contains the virus. However, hepatitis B virus is not transmitted through the digestive tract. Moreover, the immunization program for mother-to-child transmission of hepatitis B has been implemented in China, and 85% to 90% of newborns can be blocked from mother-to-child transmission, so the possibility of transmitting hepatitis B to the fetus through breastfeeding is very small. However, it is important to mention that a small amount of blood containing hepatitis B virus can cause blood transmission, so although hepatitis B is not transmitted through the digestive tract, if the newborn’s mouth is lightly mucous membrane damaged, the mother’s hepatitis B HBV-DNA quantification is high, and the newborn is an immune failure, then breastfeeding may cause the reality of mother-to-child transmission. Whether you can breastfeed can be divided into the following cases: 1, the mother’s pre-pregnancy test for a small triple-positive, and HBV-DNA negative, you can rest assured that the use of breastfeeding method. 2, the mother’s pre-pregnancy test HBV-DNA quantification in the sixth power of 10 or more, after the birth of the newborn baby, it is best to immediately check its cord blood, if Australia anti positive, try not to take breastfeeding (because the mother-infant blockage may fail). 3. If the mother’s pre-pregnancy test HBV-DNA quantification is below the 6th power of 10, the newborn’s cord blood is negative for AUD (E antigen may be positive or negative), and the newborn has no oral disease, breastfeeding can be considered. For those with positive cord blood E antigen, 6 months, 12 months should continue to check if it disappears, if it turns negative, breastfeeding will be safer. 4.If the local situation, the newborn is born without leaving cord blood for the newborn to be checked, it can only be judged with reference to the mother’s pre-pregnancy or mid-pregnancy HBV-DNA level, which is still bounded by the 6th power of 10. 5, if the pregnant woman took antiviral treatment in the second trimester of pregnancy, the treatment should continue to be maintained for one month after delivery and can be breastfed with confidence. If the pregnant woman is taking antiviral treatment for hepatitis or other reasons during the whole pregnancy, she can breastfeed safely after delivery.