Breast Enlargement In Adolescent Boys

Why does this occur?

Enlarged or swollen breasts are seen quite frequently in teenage boys. This is called “pre-pubertal gynecomastia”. As a boy enters puberty, many hormones are made that act to develop secondary sex characteristics such as, pubic hair, genital growth and deeper voice. This complex process, controlled by the brain, results in high levels of hormones in the body. Some of these hormones originate from and thus resemble female hormones.

In some boys the levels are so high, the breast gets stimulated to grow by the female type of hormones. It is not unusual that some boys, and even girls, develop breast buds at a different pace; in other words, one breast is larger than the other. This occurs because there may be a difference in sensitivity to the hormone by each breast. Because the breast tissue is stimulated, the breast may be tender or painful. A thorough physical examination is usually enough to confirm the diagnosis related to pubertal changes which usually resolve in 1-2 years. Once the cause is confirmed, some pressure is taken off as there is no need to worry.

How can boys cope with enlarged breasts?

Although not a serious medical problem, the social effects of enlarged breasts on boys may be quite worrisome. Adolescent boys are quite sensitive to being picked on, and of course this can be a source of embarrassment in public. While recognizing that this is a potential source of stress and shame, the answer is not to completely withdraw from activities that expose the enlarged breasts.

Depending on the situation, a boy can wear a T-shirt with a bathing suit saying that he was sun-burned as an example. On the other hand if a boy understands that it is just a temporary and normal part of growing up and is mature enough to be able to tell this to his friends and school mates, this is another route.

The extent to which a boy should shy away from these situations depends on the degree of shame or embarrassment the affected boy feels… not necessarily what he is called. Happily, in most situations boys can live through this period and really not suffer psychologically in the long term. Support, understanding and clear explanations go a long way in helping teenage boys deal with temporarily enlarged breasts during puberty.


As you can see form the survey below, published in the New England Journal of Medicine(1993;328:490-5), a fair amount of normal teenage boys experience breast enlargement.

Survey results: Normal teenage boys with breast enlargement:

  • 1865 American scouts, aged 10 to 16 – 39%
  • 993 Turkish schoolboys, aged 9 to 17 – 7%
  • 29 American schoolboys, at puberty – 69%
  • 681 Italian schoolboys, aged 11 to 14 – 33%
  • 135 Swiss youths, aged 8.5 to -17.5 – 22%
  • 377 American schoolboys, aged 10 to 15 – 49%

Printer Friendly Version

Pediatrician DR.PAUL Roumeliotis is certified by the American Board of Pediatrics and Royal College of Physicians and Surgeons of Canada. The information provided above is designed to be an educational aid only. It is not intended to replace the advice and care of your child’s physician, nor is it intended to be used for medical diagnosis or treatment. If you suspect that your child has a medical condition always consult a physician.