by Shanna R. Cox, M.D., F.A.A.P.
Published on May. 24, 2010
“Doctor, my baby has breasts!” On more than one occasion I have been greeted with this exclamation from new parents as I enter the room. First time parents, frequently changing their baby, may notice that either their male or female infant has what may appear as swollen or firm breasts.
In the first few weeks of life, this is a normal manifestation of breast tissue that will resolve spontaneously in most cases. It is caused by circulating maternal hormones that crossed into fetal circulation through the placenta and have made their way to the newborn’s breast tissue. In some cases this development may also be associated with milky white discharge from the nipple. In the past this discharge was often referred to as “witch’s milk.” Many believed this to be an abnormal reaction that indicated “possession” of the infant by a witch. Clearly this theory lost favor, along with many other superstitious beliefs, centuries ago.
The two-to-three centimeter firm bud usually subsides over the first few months of life. This bud is not commonly associated with redness, and is not hot to the touch. The bud does not typically grow once it is noticed. It’s presence or absence in a newborn holds no consequence for future early breast development during adolescence. If parents note the bud to be changing in size, or should it develop any surrounding redness, this should immediately be reported to the child’s pediatrician. Bloody discharge should also be checked immediately. These symptoms may be indicative of an infection in the breast tissue, or of a clogged duct that may need further medical attention. Under no circumstances should parents squeeze or prod their infant’s breast tissue.
Occasionally toddlers may also be noted to have a similar breast development. This may be due to a few different etiologies. Toddlers may simply have fat tissue that appears like breasts. A pediatrician may distinguish this difference by palpation, and the presence or absence of a breast bud.
If there is a bud that is appreciated, the toddler likely has a condition known as benign thelarche. Benign thelarche is more common in females, and is related to an increased circulating estrogen level. It occurs most often in toddlers under the age of three. It may grow in proportion with the toddler for approximately six months prior to receding. Alternatively, the breast tissue may remain unchanged into puberty. In either of these cases, this early change should not signal an early onset of puberty or an abnormal growth of the mature breast.
The exception to these situations is when the breast development is rapidly changing, or is associated with other signs of puberty. If an infant or toddler also presents with the development of odor and/or axillary or pubic hair, or growth in genitalia, an underlying over production of hormones must be considered. This may occur in disorders of the thyroid, brain, or reproductive organs. In this case, a pediatrician would involve the help of an endocrinology specialist to fully investigate the nature of these premature manifestations. Evaluation typically might include looking at blood work and radiological study.