ADAM Health Encyclopedia

Gynecomastia

Definition

Gynecomastia is the development of abnormally large breasts in males.

Alternative Names

Considerations

The condition may occur in one or both breasts and begins as a small lump beneath the nipple, which may be tender. The breasts often enlarge unevenly. Gynecomastia during puberty is not uncommon and usually goes away over a period of months.

In newborns, breast development may be associated with milk flow (galactorrhea). This condition usually lasts for a couple of weeks, but in rare cases may last until the child is 2 years old.

Causes

The most common cause of gynecomastia is puberty.

Other causes include:

• Chronic liver disease
• Exposure to anabolic steroid hormones
• Exposure to estrogen hormone
• Genetic disorders
• Kidney failure
• Marijuana use
• Side effects of some medications
• Testosterone (male hormone) deficiency

Rare causes include:

• Genetic defects
• Overactive thyroid
• Tumors

Home Care

Apply cold compresses and use analgesics as your health care provider recommends if swollen breasts are also tender.

When to Contact a Medical Professional

Call your health care provider if the breasts have developed abnormally or if there is swelling or pain in one or both breasts.

Note: Gynecomastia in children who have not yet reached puberty should always be checked by a health care provider.

Your health care provider will take a medical history and perform a physical examination.

Medical history questions may include:

• Is one or both breasts involved?
• What is the age and gender of the patient?
• What medications is the person taking?
• How long has gynecomastia been present?
• Is the gynecomastia staying the same, getting better, or getting worse?
• What other symptoms are present?

Testing may not be necessary, but the following tests may be done to rule out certain diseases:

• Blood hormone level tests
• Breast ultrasound
• Liver and kidney function studies
• Mammogram

Intervention:

If an underlying condition is found, it is treated. Gynecomastia during puberty usually goes away on its own; however, persistent, extreme, or uneven breast enlargement may be embarrassing for an adolescent boy. Breast reduction surgery may be recommended.

After seeing your health care provider:

If your health care provider made a diagnosis related to gynecomastia, you may want to note that diagnosis in your personal medical record.