The medical term for breast formation in men is ‘gynaecomastia’. It is caused by a hormonal imbalance between estrogens and androgens. In most cases it occurs bilaterally, ie on both breasts. Usually it is asymptomatic. In older age, other factors, such as certain disorders, may also play a role in the development of gynecomastia. Breast development in the man often affects both breasts, sometimes only one breast. Breast formation does not have to be symmetrical. For example, the one breast may be larger than the other breast. Physiological gynecomastia can be treated as a medical or surgical treatment if necessary.

Excessive development of the male mammary glands

Gynecomastia is breast formation in men, or an excessive development of the male mammary glands, which is caused by a hormonal imbalance between estrogens and androgens. It can occur on both sides, but it can also happen on one side. It is basically asymptomatic.

Normal phenomenon

In boys, it is common that the male mammary glands swell during puberty. This stimulation of the growth of mammary gland tissue in puberty is usually short-lived, but can also last for a few years. In babies too, this breast formation in boys can be a ‘normal’ physiological phenomenon.

In older men

Gynecomastia also occurs in middle-aged men. This phenomenon can occur as a result of normal changes in hormone levels, but breast formation can sometimes also signal a serious underlying disease.

No serious problem

Gynecomastia is not a serious problem in general, but for many boys / men it is an embarrassing problem. Gynecomastia can disappear spontaneously. If the problem persists, medication or surgery can provide a solution.


A breast that has been enlarged by fat accumulation is called pseudogynaecomastia.

Gynecomastia complaints and symptoms
Signs and symptoms of gynecomastia include:
Swollen mammary gland tissue; and
Breast shaping.

When to Consult?

Consult a doctor in the following cases:
Sensitivity; and
Separation from one or both nipples.

Causes breast formation in Men

Gynecomastia occurs as a result of a disturbance of the hormonal balance between estrogens and androgens. There is a preponderance of the amount of estrogen, which stimulates the growth of the mammary gland tissue. In babies, the mammary glands in both girls and boys are increased by the action of estrogens of the mother. This swelling disappears in a few weeks.

Gynecomastia in Puberty

Gynecomastia in (pre) puberty can also be explained by this temporary hormonal imbalance. It is also conceivable that in some boys the glandular tissue is extra sensitive to the effects of estrogens. Gynecomastia is quite common during puberty; the prevalence in the age between 10 and 15 years is around 50%. It can be regarded as a normal physiological phenomenon. In most cases, the swollen breast tissue will leave within six months to two years without treatment.

Gynecomastia in men in later life can be explained by a gradual decline in androgen production and increase in estrogen proliferation. It mainly occurs in men between the ages of 50 and 80. The highest prevalence is found in the group between 50 and 69 years (72%). However, one must be aware of other causes, such as:

Side effect of certain medications. The use of some medications can lead to gynecomastia, website Examples include: anti-androgens used to treat prostate enlargement; Anabolic steroids and androgens; Tricyclic antidepressants; Antibiotics; Stomach ulcers, such as cimetidine; Hormone therapy in connection with cancer.

Alcohol and drugs. Drugs that can lead to gynecomastia include: alcohol, amphetamines, marijuana, heroin and methadone.
Diseases. Various disorders can cause gynaecomastia, because they disturb the normal balance of hormones. Examples are: a thyroid gland, a liver disease or a tumor in the adrenal gland or testicle.

In most cases, however, no cause is found for gynaecomastia

Treatment Gynaecomastia

If no indications are found that indicate one of the above diseases or a medical cause, the general practitioner will suffice with reassurance of the patient and possible monitoring after three to six months.ยน In 92% of the boys, gynaecomastia disappears spontaneously within two years. If the deviation lasts longer, further investigation or referral to a specialist may take place. No spontaneous regression occurs in old age. Physiological gynecomastia can be treated medicinally if necessary. Surgical therapy can also offer a solution.