Generally frozen breastmilk can be kept for about 6 months. When breastmilk is produced in large quantities and the baby cannot suckle all of it, the mother can use a breast pump to express some of the breastmilk and place it in the refrigerator for freezing, and it can usually be kept for about 6 months at -15℃ to -5℃. If the mother puts the expressed breastmilk in the refrigerator at 0 to 4 degrees, it can be kept for 48 hours to prevent bacteria growth and loss of nutrients in the breastmilk if it is left for too long. In special circumstances when frozen breastmilk is needed, the frozen breastmilk should be thawed at room temperature in advance, and should not be heated under water. Fresh breastmilk is generally recommended in clinical practice, and mothers should also pay attention to feeding on demand to ensure that their babies have the necessary nutrients. It is recommended that frozen breastmilk should be properly preserved. If it has been left for more than half a year or has deteriorated, it should be discarded in time to avoid feeding the baby again. Mothers should pay attention to the rationality of their diet to ensure a balanced intake of nutrients.