Gynecomastia: Symptoms, Causes, Complications, Risk Factors, Diagnosis and Treatment

What is Gynecomastia?

Gynecomastia is a swelling of the breast tissue in children or in men, caused by an imbalance of the hormones estrogen and testosterone. Gynecomastia can affect one or both breasts, sometimes unevenly.

Newborns, children going through puberty and older men can develop gynecomastia as a result of normal changes in hormone levels, although there are other causes as well.

In general, gynecomastia is not a serious problem, but it can be difficult to cope with the condition. Men and children with gynecomastia sometimes have pain in their breasts and may feel embarrassed.

Symptoms of a gynecomastia

The signs and symptoms of gynecomastia include: Inflammatory tissue of the mammary gland and breast tenderness.

The prevalence of asymptomatic gynecomastia is 60% to 90% in neonates, 50% to 60% in adolescents and up to 70% in men from 50 to 69 years.

The prevalence of symptomatic gynecomastia is markedly lower. A selection of gynecomastia in 214 adult men hospitalized from 27 to 92 years revealed that 65% had gynecomastia, defined in this study as nodule size greater than 2 cm; however, none of them was symptomatic.

The variation in prevalence reported between the studies is attributed to the variations in the size of the palpable breast tissue used to define gynecomastia and the characteristics of the population such as age and the start of treatment.

Although breast cancer is rare in men, those who have gynecomastia often become anxious and seek medical attention, making this presentation quite common in primary care settings.

The diagnostic evaluation of these cases can be expensive and involves laboratory and radiographic tests. Therefore, a diagnostic algorithm that facilitates step-by-step evaluation can be cost-effective and reduce the anxiety of the associated patient.

If a case of gynecomastia is suspected, when should a doctor be consulted?

Consult your doctor if you have swelling, pain, tenderness, nipple discharge in one or both breasts.

Causes of gynecomastia

Gynecomastia is triggered by a decrease in the amount of the hormone testosterone compared to estrogen.

The cause of this decrease is that conditions block the effects of or reduce testosterone or a condition that increases the level of estrogen in men.

Several things can alter the hormonal balance, including the following:

  • Natural hormonal changes: the hormones testosterone and estrogen control the development and maintenance of sex characteristics in both men and women.

Testosterone controls male traits, such as muscle mass and body hair. Estrogen controls female characteristics, including the growth of breasts.

  • Most people think of estrogen as an exclusively female hormone, but man also produces it, although usually in small amounts.

However, male estrogen levels that are too high or out of balance with testosterone levels can cause gynecomastia.

  • Gynecomastia in babies: more than half of boys are born with enlarged breasts due to the effects of their mother’s estrogen.

Generally, swollen breast tissue disappears within two to three weeks after birth.

  • Gynecomastia during puberty: gynecomastia caused by hormonal changes during puberty is relatively common.

In most cases, the swollen breast tissue will disappear without treatment within six months to two years.

  • Gynecomastia in men: the prevalence of gynecomastia again increases between 50 and 69 years. At least 1 in 4 males in this age group is affected.

Drugs that can cause gynecomastia

A series of medications can cause gynecomastia. These include:

  • Anti-androgens used to treat enlarged prostate, prostate cancer and some other conditions. Examples include flutamide, finasteride (Proscar, Propecia) and spironolactone (Aldactone).
  • Anabolic steroids and androgens.
  • AIDS. Gynecomastia can develop in HIV-positive men who are receiving a treatment regimen called highly active antiretroviral therapy (HAART). Efavirenz (Sustiva) is more commonly associated with gynecomastia than other HIV medications.
  • Anti-anxiety medications, such as diazepam (Valium).
  • Tricyclic antidepressants.
  • Antibiotics
  • Medications for the ulcer, such as cimetidine (Tagamet HB).
  • Treatment against cancer (chemotherapy).
  • Drugs for the heart, such as digoxin (Lanoxin) and calcium channel blockers.
  • Gastric motility medications, such as metoclopramide (Reglan).
  • Drugs in the street and alcohol

Substances that can cause gynecomastia include:

  • Alcohol
  • Amphetamines
  • Marijuana
  • Heroin
  • Methadone
  • Finally, the health conditions that suddenly can be presented.

Several health conditions can cause gynecomastia by affecting the normal balance of hormones. These include:

  • The Hypogonadism : any conditions that interfere with normal testosterone production, such as Klinefelter syndrome or pituitary insufficiency may be associated with gynecomastia.
  • Aging: the hormonal changes that occur with normal aging can cause gynecomastia, especially in men who are overweight.
  • Tumors: Some tumors, such as those that affect the testicles, the adrenal glands or the pituitary gland, can produce hormones that alter the male-female hormone balance.
  • Hyperthyroidism : in this condition, the thyroid gland produces too much of the hormone thyroxine.
  • Renal insufficiency : approximately half of the people treated with regular hemodialysis experience gynecomastia due to hormonal changes.
  • Hepatic insufficiency and cirrhosis : hormonal fluctuations related to liver problems, as well as medications taken for cirrhosis are associated with gynecomastia.
  • Malnutrition and hunger: when your body is deprived of adequate nutrition, testosterone levels fall, but estrogen levels remain constant, causing hormonal imbalance.

Gynecomastia can also occur once normal nutrition is resumed.

Herbal products that can cause it

Vegetable oils, such as tea tree or lavender, used in shampoos, soaps or lotions have been associated with gynecomastia. This is probably due to its weak estrogenic activity, which however for some cases may be notorious.


The imbalance between the action of estrogens in relation to the action of androgens at the level of breast tissue seems to be the main etiology of gynecomastia.

Elevated levels of serum estrogens can result from estrogen-secreting neoplasms or their precursors (eg, Leydig or Sertoli cell tumors, chorionic gonadotropin-producing tumors (hCG), and adrenocortical tumors.

But more commonly they are caused by increased extragonadal conversion of androgens to estrogen by tissue aromatase (as in obesity ).

Free serum testosterone levels decrease in patients with gonadal insufficiency, which can be primary (Klinefelter syndrome, mumps orchitis, castration) or secondary ( hypothalamus and pituitary ).

Syndromes of androgen resistance due to the alteration of the activity of enzymes involved in the biosynthesis of testosterone may also be associated with gynecomastia.

The balance between free testosterone and estrogen is also affected by serum levels of globulin binding to sex hormones, which is the proposed mechanism of gynecomastia in certain conditions, such as hyperthyroidism , chronic liver disease and the use of some medications such as spironolactone .

Androgen receptors may also have genetic defects or be blocked by certain medications (eg, Bicalutamide, used in the treatment of prostate cancer ) and estrogen receptors may be activated by certain medications or environmental exposures.

It should be noted that in patients with puberty, gynecomastia has normal levels of serum estradiol, testosterone and dehydroepiandrosterone sulfate and a normal ratio of estrogen-testosterone.

However, free testosterone levels in these patients are lower than those in controls without gynecomastia.

Eventually, exposure to hormonal imbalance leads to the proliferation of glandular tissues, that is, ductal hyperplasia.

Risk factor’s

Risk factors for gynecomastia include:

  • Adolescence
  • Advanced age
  • Use of anabolic steroids or androgens to improve athletic performance
  • Certain health conditions, including liver and kidney disease, thyroid disease, hormonally active tumors and Klinefelter syndrome.


Gynecomastia has few physical complications, but can cause psychological or emotional problems caused by the unexpected and unwanted appearance of male “breasts”

Diagnosis of a Gynecomastia

Your doctor will ask you questions about your medical and medication history and about the health conditions that run in your family. The doctor will also do a physical exam that may include a careful evaluation of your breast tissue, abdomen and genitals.

Initial tests to determine the cause of your gynecomastia may include:

  • Blood test
  • Mammograms
  • You may need more tests depending on the results of your initial test, including:
  • Computed tomography (CT)
  • Magnetic resonance imaging (MRI)
  • Testicular ultrasound
  • Tissue biopsies
  • Conditions that cause similar symptoms

Your doctor will want to make sure that your chest swelling is actually gynecomastia and not another condition. Other conditions that can cause similar symptoms are:

  • Fatty breast tissue: some men and boys have chest fat that resembles gynecomastia. This is called false gynecomastia (pseudogynecomastia), and is not the same as gynecomastia.
  • Breast cancer: this is uncommon in men, but it can occur. The enlargement of a breast or the presence of a firm nodule raises the concern for male breast cancer.
  • A breast abscess (mastitis): this is an infection of the breast tissue.

A review of all mammographic findings for men over a 5-year period revealed a malignancy rate of 1%.

The majority of the cases were due to benign causes; Of these, gynecomastia accounted for 62%, with other causes including lipomas, dermoid cysts, sebaceous cysts, lymphoplasmacytic inflammation, ductal ectasia, bruising and fat necrosis.

In contrast, the differential diagnosis of gynecomastia per se, as demonstrated in a series of (25%), hyperprolactinemia (9%), chronic liver disease (4%) and drug-induced gynecomastia (4%), 10 young patients with Gynecomastia from 19 to 29 years of age, include idiopathic gynecomastia (58%).

The frequency distribution of these etiologies is imprecise due to the small number of cases reported in the literature and can vary widely between publications and practice.


In general, gynecomastia is a benign condition and is usually self-limited. Over time, the fibrotic tissue replaces the symptomatic proliferation of the glandular tissue.

If adequate treatment does not reveal a significant underlying disease, periodic follow-up is recommended. Although there is a lack of evidence to support a recommendation for follow-up intervals, 6 months seems reasonable.

The causative drugs must be withdrawn or the underlying medical conditions causing (eg, hyperthyroidism) must be addressed. Most cases of pubertal gynecomastia usually resolve in less than a year.

If the gynecomastia persists and is associated with pain or psychological disorder and if the patient wishes to continue the treatment, there are pharmacological and surgical options.

Pharmacotherapy is beneficial if it is implemented before the fibrous tissue replaces the glandular tissue, while surgery can be performed at any time.