Part of the newborn nipple will grow out, because the newborn body has from the mother’s body secretion of hormones, nipple will appear to develop, this is a normal physiological phenomenon. Newborns nipple growth is affected by the mother’s estrogen, progesterone and prolactin, estrogen and progesterone can promote the baby mammary glands to increase in size, prolactin can promote the baby lactation. The hormones from the mother in the newborn’s body will basically disappear in 2 to 3 weeks, and then the enlargement of the mammary glands and the phenomenon of lactation will also disappear on its own. Parents should not squeeze the nipples, because squeezing the nipples of newborn babies can easily lead to skin infections, and the nipples may become pus-filled. If the newborn nipple grows out of the situation, you can go to the pediatrician for consultation, do not blindly take measures, so as not to cause adverse consequences.