Breastfeeding is not recommended when hepatitis B virus DNA quantification exceeds 2×105 kIU/L. According to the 2020 edition of the Clinical Guidelines for the Prevention of Mother-to-Child Transmission of Hepatitis B Virus, one of the major risk factors for mother-to-child transmission is breastfeeding. High viral levels in pregnant women, i.e., quantification of hepatitis B virus DNA (HBVDNA) greater than 2×105 kIU/L. The guidelines provide for fluorescent real-time quantitative PCR technology to detect, peripheral blood hepatitis B virus DNA (HBVDNA) levels, i.e., viral levels, which can reflect whether viral replication is active. HBVDNA>2x105kIU/L (i.e., IU/ml) is usually considered to have active viral replication and is referred to as a high viral level, or high viral load. When the quantification of hepatitis B virus DNA (HBVDNA) is greater than 2×105 kIU/L, the mother is highly infectious, and at this time breastmilk is highly susceptible to infection of infants, and transmission of the hepatitis B virus through mother-to-child feeding. It is recommended that pregnant women with hepatitis B should seek medical treatment in time, and carry out proper feeding and antiviral treatment according to the doctor’s instructions, and should not make judgment on their own, so as to avoid adverse consequences.