Breast Enlargement in Adolescent Boys

By Dr. Paul Roumeliotis

DEAR DR.PAUL:
My 13 year-old son is embarrassed to go swimming because his breasts are enlarged and sometimes painful. Aside from the effect on him emotionally, I am concerned about this. Is breast enlargement normal in boys?

PEDIATRICIAN DR.PAUL ANSWERS:
Breast enlargement or "physiologic pubertal gynecomastia", develops in up to 65% of normal boys. All children who enter puberty produce both female hormones, called estrogens, and male hormones known as androgens. Androgens cause the development of the male secondary sex characteristics such as pubic hair, genital growth and a deeper voice. Estrogens are responsible for the development of female sex characteristics such as breast enlargement.

This complex process of pubertal hormone production is controlled by the brain and results in temporary high levels of both androgens and estrogens. During this period, the high estrogen levels may stimulate breast enlargement in some boys. It is not uncommon for one breast to be enlarged and not the other. In some cases, both breasts are affected. Frequently, the breasts may be tender or painful. Very rarely, breast enlargement, especially in younger boys, may be caused by a more serious problem. However, a thorough physical examination is usually enough to confirm the diagnosis of pubertal breast enlargement in teenage boys, which usually resolves on its own within in one to two years.

Knowing this fact is quite reassuring to most boys and their parents. However, the social effect on the boy's self image needs to be evaluated. Adolescent boys are quite sensitive to being picked on, and of course, enlarged breasts can be a source of embarrassment in public. While recognizing this is a potential source of stress and shame, I do not think the answer is to completely withdraw the boy from swimming and other sporting activities. At the pool or beach, or even during outdoor summer sporting events, wearing a T-shirt under the guise of "sun sensitivity" for example, may do the trick. On the other hand, this situation can be dealt with if a boy understands that it is just a normal part of growing up and is mature enough to be able to explain this to his friends, teammates and schoolmates.

Again, the extent to which a boy's lifestyle is affected depends on the degree of shame or embarrassment he feels or experiences. Happily, most adolescent boys can get through this period very well by having supportive parents and a clear understanding of the normal and temporary nature of enlarged breasts during puberty.

Since I am on the topic of the effect of hormones on breast tissue, it is not uncommon for newborn baby girls and boys to have engorged and slightly enlarged breasts at birth. This breast enlargement is caused by estrogens passed from the mother to the baby during the pregnancy. At birth, this hormone transfer stops and the breasts return to normal size within a week or two.