Testicular dysfunction or male hypogonadism is a condition in which the body doesn’t produce enough testosterone — the hormone that plays a key role in masculine growth and development during puberty — or has an impaired ability to produce sperm or both.
You may be born with male hypogonadism, or it can develop later in life, often from injury or infection. The effects — and what you can do about them — depend on the cause and at what point in your life male hypogonadism occurs.
Some types of male hypogonadism can be treated with testosterone replacement therapy.
Symptoms
Male reproductive system
Hypogonadism can begin during fetal development, before puberty or during adulthood. Signs and symptoms depend on when the condition develops.
Fetal development
If the body doesn’t produce enough testosterone during fetal development, the result may be impaired growth of the external sex organs. Depending on when hypogonadism develops and how much testosterone is present, a child who is genetically male may be born with:
• Female genitals
• Ambiguous genitals — genitals that are neither clearly male nor clearly female
• Underdeveloped male genitals
Puberty
Male hypogonadism may delay puberty or cause incomplete or lack of normal development. It can cause:
• Decreased development of muscle mass
• Lack of deepening of the voice
• Impaired growth of body hair
• Impaired growth of the penis and testicles
• Excessive growth of the arms and legs in relation to the trunk of the body
• Development of breast tissue (gynecomastia)
Adulthood
In adult males, hypogonadism may alter certain masculine physical characteristics and impair normal reproductive function. Signs and symptoms may include:
• Erectile dysfunction
• Infertility
• Decrease in beard and body hair growth
• Decrease in muscle mass
• Development of breast tissue (gynecomastia)
• Loss of bone mass (osteoporosis)
Hypogonadism can also cause mental and emotional changes. As testosterone decreases, some men may experience symptoms similar to those of menopause in women. These may include:
• Fatigue
• Decreased sex drive
• Difficulty concentrating
• Hot flashes
The production of testosterone occurs within the Leydig cells of the testes. When production fails at this level from either congenital, acquired, or systemic disorders, the result is primary hypogonadism. While numerous testosterone formulations have been developed, none are yet fully capable of replicating the physiological patterns of testosterone secretion. Multiple stem cell therapies to restore androgenic function of the testes are under investigation. Leydig cells derived from bone marrow, adipose tissue, umbilical cord, and the testes have shown promise for future therapy for primary hypogonadism.