HYPOGONADISM
Male hypogonadism is a condition in which the body doesn't produce enough of the sex hormone testosterone. As many as 5 million men in the United Sates may not produce enough testosterone — the hormone that plays a key role in masculine growth and development during puberty.
Testosterone's effects begin after conception, stimulating the formation of male sex organs. The hormone continues to play an important role through puberty and adulthood by triggering male characteristics and maintaining sex drive.
You may be born with hypogonadism, or it can develop later in life from injury or infection. The effects — and what you can do about them — depend on the cause and at what point in your life hypogonadism occurs.
During fetal development, low testosterone can cause incomplete formation of sex organs. Low testosterone levels before puberty can permanently affect growth and development. After puberty, the development of hypogonadism is more likely to cause temporary problems that may improve with treatment. Some types of hypogonadism can be treated with testosterone replacement therapy.
Signs and symptoms
Hypogonadism can occur during fetal development, puberty or adulthood. Depending on when it develops, the signs and symptoms differ.
Fetal development
If the body doesn't produce enough testosterone during fetal development, growth of external sex organs may be impaired. Depending at when it develops, and how much testosterone is present, a child that is genetically male may be born with:
- Female genitals
- Ambiguous genitals (genitals that are neither clearly male or female)
- Underdeveloped male genitals
Puberty
During puberty, male hypogonadism may slow growth and affect 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
- Increase in body fat
- Decrease in size or firmness of testicles
- 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
- Irritability
- Depression
Causes
Male hypogonadism means the testicles don't produce enough of the male sex hormone testosterone. There are two basic types of hypogonadism:
Primary. This type of hypogonadism — also known as primary testicular failure — originates from a problem in the testicles.
Secondary. This type of hypogonadism indicates a problem in the hypothalamus or the pituitary gland — parts of the brain that signal the testicles to produce testosterone. The hypothalamus produces gonadotropin-releasing hormone, which signals the pituitary gland to make follicle-stimulating hormone (FSH) and luteinizing hormone. Luteinizing hormone then signals the testes to produce testosterone.
Either type of hypogonadism may be caused by an inherited (congenital) trait or something that happens later in life, such as an injury or an infection (acquired)
