When the adolescent male suddenly develops noticeable breast tissue under each nipple he becomes worried, embarrassed and uncomfortable. This condition is called gynecomastia. This is the development of mammary (breast) tissue in males. In otherwise healthy boys, it is seen commonly in two age groups: during the newborn period and during mid-puberty.
In newborns, breast development is the result of circulating maternal hormones, and most male newborns are affected. In mid-puberty, approximately two-thirds of boys develop varying amounts of breast tissue, either in one or both breasts, at the same or at different times. There may or may not be some breast tenderness. This breast development results from the normal hormonal changes seen during puberty.
Emotionally, the adolescent is very sensitive to this physical finding. Parents or siblings should never joke about the matter. School mates are sometimes less thoughtful and tease the youth about "breast development". The parents should reassure him that it is a transient phenomenon.
Usually, this condition regresses within a few months, rarely taking longer than 24 months.
Researchers have noted that in these boys the value for various male and female hormone tests are within the normal range, but there is a decreased ratio of male hormone (testosterone) to the female hormone (estradiol). The male hormones are normal and this transient tissue is present until all the hormones are produced in the usual proportions. This tells the worried boys that their "maleness" is not threatened, and they can better tolerate the teasing they must endure.
When gynecomastia occurs in otherwise healthy boys, reassurance and education are the mainstays of treatment. There is no need for medication in this temporary condition. Less commonly, there is a condition called familial gynecomastia, where the breast development fails to regress. This condition runs in families, and the exact genetic defect is unknown.
Gynecomastia can also occur through the ingestion or topical application of the female hormone, estrogen. Usually this is the result of accidental poisoning and is seen in young children. Additionally, long-term use of anabolic steroids, as seen during body-building, can lead to gynecomastia.
In otherwise healthy boys, breast development during puberty is a harmless and temporary condition. If more information is needed your son's doctor will be able to provide him with proper education, so that he has a better understanding of his present condition.