Can I continue breastfeeding if my breast milk is cytomegalovirus positive? Excretion of CMV in the milk of cytomegalovirus (CMV) IgG-positive mothers is common and mostly intermittent. The peak of CMV excretion in breast milk is 4-6 weeks after delivery, with a significantly higher rate of infection acquired after more than 1 month of breastfeeding. Current studies have confirmed that CMV infection in postnatal infants is primarily derived from CMV-containing breast milk. Perinatal and postnatal CMV infections are benign, self-limiting diseases with no significant near-term or long-term effects on full-term infants. A multicenter study in Beijing in which our hospital participated showed that the percentage of perinatal CMV infection was 20.27% and 66.69% at the age of 1 year. The difference in clinical manifestations between CMV-infected and uninfected infants was not statistically significant, confirming that perinatal and postnatal CMV infection had no significant effect on growth and development. Breast milk contains suitable nutrients and rich immunologically active substances, which is an important material basis for defense against pathogenic bacteria and is the most ideal food for infants. Although there is a risk of perinatal CMV infection, the advantages still outweigh the disadvantages relative to the growth and development of the infant and the reduction of serious illness. Moreover, CMV lgG positive women of childbearing age in China account for more than 90%, and most mothers have the possibility of detoxification in breast milk during breastfeeding, and it is difficult to achieve under the existing conditions hoping to completely avoid CMV in breast milk, therefore, for healthy full-term infants, even if the breast milk is positive for CMV, they can still continue breastfeeding and generally do not cause significant effects on the infant. It is important to note that preterm infants born to CMV IgG-negative mothers and very low birth weight infants born to CMV IgG-positive mothers who develop perinatal CMV infection. Serious lesions may occur. It has been observed that 38% of very low birth weight infants acquire CMV infection from the breast milk of serologically positive mothers, and 48% of them have symptomatic infection with CMV “sepsis-like syndrome”, with clinical manifestations including hepatosplenomegaly, apnea, bradycardia, intestinal distention, pallor, leukopenia, and thrombocytopenia. In view of the risk of perinatal infection to very low birth weight infants, many experts suggest that feeding the breast milk of IgG-positive mothers to very low birth weight infants after pasteurization or freezing at one 20°C may reduce the activity of CMV. There are many similar reports from abroad, but the results are inconsistent and further studies are needed.