Male hypogonadism is a medical condition where the testes do not produce sufficient amounts of testosterone, the primary male sex hormone. This deficiency can impact males at any stage of life, from before birth through adulthood, and its effects vary depending on when it begins. The condition can arise from issues within the testes or from problems with the brain’s hormonal signaling pathways.
Types and Causes of Male Hypogonadism
Male hypogonadism is categorized into two main types: primary and secondary. In primary hypogonadism, the problem originates directly within the testicles, which fail to produce adequate testosterone despite receiving proper signals from the brain. This form is also known as primary testicular failure. Common causes include genetic conditions like Klinefelter syndrome, physical injury, undescended testicles, and complications from infections like mumps orchitis.
Secondary hypogonadism occurs when the testicles are functional but do not receive the necessary signals from the brain to produce testosterone. The issue lies within the hypothalamus or the pituitary gland. The hypothalamus produces gonadotropin-releasing hormone (GnRH), which prompts the pituitary to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH). LH is the direct signal for testosterone production. Causes of secondary hypogonadism include pituitary disorders, inflammatory diseases like sarcoidosis, obesity, and the use of certain medications.
Signs and Symptoms
The signs of male hypogonadism depend on the age when the testosterone deficiency begins. When the condition develops in adulthood, symptoms can significantly affect quality of life. Men may experience:
- Decreased sex drive, erectile dysfunction, and infertility
- A reduction in muscle mass and strength
- Loss of body and facial hair
- Increased body fat
- Development of breast tissue (gynecomastia)
Beyond the physical changes, adult-onset hypogonadism can cause emotional and cognitive effects. Many men report persistent fatigue, low energy levels, and mood swings or depression. Difficulties with concentration and memory can also occur. In severe cases, some men may experience hot flashes, similar to what women experience during menopause.
If hypogonadism occurs before or during puberty, it disrupts normal male development. An adolescent may show a lack of voice deepening, impaired growth of the penis and testicles, and underdeveloped muscle mass for his age. The growth of facial and body hair may also be sparse or absent, resulting in a physical appearance that seems younger than their chronological age.
The Diagnostic Process
Diagnosing male hypogonadism involves a physical examination, a review of symptoms, and laboratory tests. A healthcare provider will discuss the patient’s symptoms and medical history. The physical exam helps identify signs like reduced body hair, gynecomastia, or smaller testicular volume.
The diagnosis relies on blood tests to measure hormone levels. A total testosterone level blood test is the primary tool, and because testosterone levels fluctuate, this test is performed in the morning between 8 a.m. and 10 a.m., when levels are highest. An acute illness can cause a falsely low result, so it is important to be healthy during testing. To confirm a diagnosis, a low testosterone level may need to be verified on at least two separate occasions.
To determine the type of hypogonadism, doctors also measure luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In primary hypogonadism, LH and FSH levels are high as the pituitary gland tries to stimulate unresponsive testes. In secondary hypogonadism, LH and FSH levels are low or inappropriately normal, indicating a problem with the pituitary or hypothalamus signaling.
Available Treatment Options
The most common treatment for male hypogonadism is Testosterone Replacement Therapy (TRT). The goal of TRT is to restore testosterone levels to a normal range, alleviating many associated symptoms. Restoring these levels can lead to improvements in libido, energy, mood, muscle mass, and bone density. Treatment is initiated and monitored by a healthcare professional, such as an endocrinologist.
TRT is available in several forms, allowing for a choice based on preference, cost, and convenience:
- Topical gels applied daily to the skin, providing stable blood levels of the hormone
- Intramuscular injections administered every one to two weeks, or as a long-acting formula every 10 to 12 weeks
- Skin patches
- Pellets implanted under the skin every few months
- Oral tablets that are absorbed through the gums
TRT must be managed carefully by a healthcare provider. Regular follow-ups and blood tests are necessary, especially during the first year, to ensure testosterone levels are within the target range and to monitor for side effects. Side effects can include acne, an increase in red blood cell count, or breast tenderness. Because TRT can suppress the body’s natural hormone production, it can also impact sperm production and fertility, a consideration for men who wish to have children.