Careless breastfeeding when you have a fever of 39°C is divided into many cases. If a pregnant woman originally has a contagious disease and breastfeeds her child when she has a fever of 39°C, she needs to take her child to the hospital as soon as possible for immunoglobulin injection treatment. If the fever is 39℃ caused by common cold or diarrhea, there is no need to worry too much about breastfeeding, as it is less likely that viruses or bacteria will enter the child’s body through breast milk, and the mother’s milk contains more antibodies, which will help the baby to strengthen its resistance. So there is no need to be too nervous about breastfeeding at this time, just give your child more water. When the fever is 39℃, you should try to deal with it. A high body temperature can be used first by physical cooling to see if the temperature can be brought down, for example, you can use a warm towel to wipe the skin of the whole body. In addition, if the fever is caused by a cold, you can take busulfan anti-inflammatory oral solution. If the fever is caused by other reasons, go to the hospital for a specific checkup to find out the specific cause and suspend breastfeeding for the child.