What is Gynecomastia?

Gynecomastia is a condition that affects a lot of men. The causes of it range from uncommon neoplasms to benign physiological processes. The clinician must be aware of the hormonal elements involved in breast development in order to identify the cause of gynecomastia. Male breast growth requires oestrogen, growth hormone (GH), and IGF-1, much like female breast development does. Since there is a balance between oestrogen and androgens in guys, any condition or medicine that raises the ratio of oestrogen to androgen by increasing circulating oestrogens or decreasing circulating androgens might cause gynecomastia. A thorough history and physical are essential due to the variety of potential aetiologies, including neoplasms. After the reason of gynecomastia has been identified, therapy is necessary. Close observation is advised if there is no underlying reason found. Medical therapy can be tried if the gynecomastia is severe and recent-onset, and if futile, glandular tissue can be surgically removed. Please check our online FREE resource for comprehensive coverage of all linked fields of endocrinology.


Breast development and ontogeny

Similar to how female breast development happens, male breast development also takes place. The development and maturation of the adult female breast happens during puberty in females as a result of a complicated hormonal interplay.

Early in foetal development, ducts that connect to the nipple at the skin’s surface are formed from proliferating epithelial cells derived from the epidermis of the area that will eventually become the areola. Later in gestation, the blind ends of these ducts bud to produce alveolar structures. The infantile breast regresses until adolescence as a result of the fall in foetal prolactin and placental oestrogen and progesterone at birth (1).

The first clinical manifestation of the breast bud and the growth and division of the ducts take place during thelarche in females, resulting in club-shaped terminal end buds that later develop into alveolar buds. The type 1 lobule is formed by a group of about a dozen alveolar buds that have gathered around a terminal duct. The type 1 lobule will develop into the ductule-like types 2 and 3. Up to 50 alveolar buds can be found in type 2 lobules and 80 in type 3 lobules. During puberty, the entire differentiation process takes years, and if pregnancy is not attained, it may never be finished (2). Contrarily, due to the increased testosterone levels during puberty, there is typically no further breast development. Some peripubertal boys may momentarily produce type 1 lobules, which could eventually atrophy.


Pseudogynecomastia describes an increase in fat in male breasts without an increase in glandular tissue.

Gynecomastia can emerge from typical variations in hormone levels in newborns, boys going through puberty, and older men, though there are other causes as well.

Gynecomastia is typically not a significant issue, although managing the illness can be challenging. Gynecomastia can cause men and boys to experience discomfort in their breasts as well as feelings of embarrassment.

Gynecomastia could disappear by itself. Surgery or medicines might be helpful if it continues.



Gynecomastia is brought on by a drop in testosterone levels when compared to oestrogen. Conditions that impede testosterone’s actions, lower testosterone, or raise oestrogen levels may be to blame for the decline.

The following are some factors that can interfere with the hormone balance.

natural hormone alterations
Both men and women’s sex characteristics are regulated by the hormones testosterone and oestrogen. Male characteristics like body hair and muscle mass are controlled by testosterone. Estrogen regulates feminine characteristics, particularly breast development.

Contrary to popular belief, men can also generate the hormone oestrogen, albeit often in much less amounts. Gynecomastia can be brought on by male oestrogen levels that are excessive or out of whack with testosterone levels.

infant gynecomastia Because of the impact of their mother’s oestrogen, more than half of male children are born with larger breasts. After giving birth, the enlarged breast tissue often fades away in two to three weeks.
during adolescence, gynecomastia It is rather typical for hormonal changes brought on by puberty to induce gynecomastia. The enlarged breast tissue will typically go away on its own in six months to two years.
Adult gynecomastia. Between 24% and 65% of men between the ages of 50 and 80 are believed to be affected. The majority of affected men, however, have no symptoms.



Several drugs have the potential to induce gynecomastia. They consist of:

Prostate cancer, as well as other disorders, are treated with anti-androgens. Flutamide, finasteride (Proscar, Propecia), and spironolactone are among examples (Aldactone, Carospir).
Treatment of hormone deficits, delayed puberty, or muscle loss due to another illness with anabolic steroids and androgens.
medicines for AIDS. Certain HIV drugs, particularly Efavirenz, might produce gynecomastia due to their estrogen-like characteristics (Sustiva).
Amphetamine-containing ADHD medicines, such as Adderall.
Anti-anxiety drugs, such as valium (Valium).
tricyclic mood stabilisers.

Medications for ulcers, such as the over-the-counter pain reliever cimetidine (Tagamet HB).
cancer treatment using chemotherapy.
heart drugs such calcium channel blockers and digoxin (Lanoxin).
drugs that empty the stomach, such metoclopramide (Reglan).