Newborns are not allowed to express their breasts. Some of the newborns can be seen with enlarged breasts such as fava bean or walnut size, or even darkened areola area or lactation. This is generally due to the fetus in the mother’s body by the high level of hormone stimulation, belongs to the physiological performance, with the postpartum hormone level of reduction, can return to normal, do not need to carry out additional breast squeezing and other operations. The enlarged mammary glands of newborns usually subside in 2 to 3 weeks after birth, and you should never squeeze the nipples. Squeezing the nipple may lead to breast infection in the newborn. Newborns have an incomplete immune system, so if the infection is serious, sepsis and septicemia may occur, and they need to be taken to a doctor as soon as possible.