Breast milk should not be heated repeatedly, and breast milk that is refrigerated or frozen should be fed cleanly at once after heating. If the child cannot finish all the heated breastmilk at one time, it should not be heated again and fed to the child. If the breastmilk is heated repeatedly, it will easily lead to the destruction of various nutrients in the breastmilk, and the child will not be able to take in enough nutrients although he/she has eaten the breastmilk. Occasionally, it will not have a big impact, but if you repeatedly feed your child with heated breast milk, it will easily lead to nutritional deficiency and affect the physical and intellectual development of your child. Breast milk that is thawed after being frozen is more likely to be contaminated by various microorganisms and spoiled, and feeding it after repeated heating may lead to intestinal infection in babies.