You are in Medical Library . There are many causes for lumps in the breast including normal physiologic findings.
Some lumps are age dependent.
Both male and female newborn infants have lumps of enlarged breast tissue beneath the nipple which have been stimulated by maternal hormones. These disappear within a few months of birth. These lumps are breast buds and are one of the earlier signs of the beginning of puberty. These tend to disappear over a period of 6 months to 1 year. It is also important to remember that hormonal changes just prior to menstruation may cause a lumpy or granular feeling to the breast tissue.