Breast enlargement in newborns, commonly known as breast buds, is one such condition. The breast tissue beneath and surrounding the nipple is usually raised and between ¼ and ½ inch in diameter. It is very important not to press or squeeze the enlarged tissue because it can result in an abscess or infection. In approximately 5% of newborns, a white milky discharge termed 'witch's milk' is secreted from the nipples. Many parents are quite shocked to see a newborn lactating, especially a baby boy and the discovery of any lump under a baby's skin can be extremely worrisome to a parent. Breast buds however are quite common and both the buds and 'witch's milk' usually go away within 2-4 weeks (the buds will take longer to disappear with breastfed children).
For the vast majority of babies there is absolutely no need to be concerned however if you have any worries, or if the breast buds don't clear up in the first month, you should consult with your pediatrician.
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