Testosterone Replacement and Hypogonadism

Programs and Disease Treatment

Male Hypogonadism

The male testes secrete hormones called androgens, including testosterone. Male hypogonadism is a deficiency of testosterone in men. In men, hypogonadism may be associated with a deficiency of sperm production. About 5 percent to 6 percent of men experience male hypogonadism, a condition that is more common as a man ages.

There are two types of male hypogonadism:

In primary hypogonadism, the testes fail to make testosterone because of infection or injury to the testes.

In secondary hypogonadism, which is more common, the hypothalamus or the pituitary gland fails to produce enough of their respective releasing or stimulating hormones. These hormones “tell” the testes to produce testosterone. The hypothalamus produces a hormone that signals the pituitary gland to make FSH and LH. LH signals the testes to produce testosterone.

A man may be born (congenital) with either type of hypogonadism, or he may acquire it as the result of aging, disease, drugs or other factors. Symptoms may include decreased libido, erectile dysfunction, fatigue, sleep disturbances, depression and other symptoms.

Diagnosing Male Hypogonadism

Following a complete medical history and physical, tests will be done. An important test for male hypogonadism is a man’s testosterone level. Because testosterone levels fall off during the day, a testosterone blood test is done between 7:00 am and 10:00 am.

If the test shows a low testosterone level, additional tests will be done to determine if a pituitary gland disorder may be the cause. A blood test to check serum follicle-stimulating hormone (FSH), luteinizing hormone (LH) and prolactin levels can help determine the cause. If it is unclear whether FSH and LH levels are inappropriate or not and fertility is a concern, specialized testing is performed in the Endocrine Diagnostic Unit, based at Froedtert & The Medical College of Wisconsin.

Other tests may include:

Semen analysis — sperm count is assessed in men who are seeking fertility treatment.

Karyotype analysis — a blood test to detect chromosomal abnormalities, which can determine if hypogonadism has a congenital cause.

Testicular ultrasound — a test that uses sound waves to produce a picture of the testicles; this is done to check for a tumor or other abnormality.

MRI scan — magnetic resonance imaging to check for tumors or other abnormalities of the pituitary or hypothalamus glands.

Bone density evaluation — men who are deficient in testosterone have a higher risk for bone loss (osteopenia or osteoporosis); A dual energy X-ray (DEXA) test scans the bones and measures bone mineral density.

Gynecomastia evaluation — some men develop gynecomastia, or enlargement of the breast, that may be related to hypogonadism. Diagnosis includes a physical examination, history and blood tests.

Treatment Options

A man may be referred to a Medical College of Wisconsin endocrinologist to be evaluated for hypogonadism by his primary care physician or by a specialist treating the man for a related disorder (e.g., a nephrologist for kidney disease or a urologist for infertility).

For men with primary hypogonadism, treatment typically involves lifelong testosterone replacement therapy. Options for replacement therapy include:

Testosterone gel — applied on the skin
Buccal mucosal patch — placed inside the mouth
Transdermal testosterone patch — placed on the skin
Testosterone injections into the muscles

Fertility treatment

Infertility related to secondary hypogonadism may respond to hormonal replacement therapy, which involves replacement of LH and FSH. Infertility related to primary hypogonadism, however, does not respond to hormonal therapy. In these cases, a patient may be referred to a Medical College of Wisconsin reproductive medicine physician. The referring endocrinologist maintains close communication with the reproductive medicine physician.

Too much testosterone can place a man at a higher risk for blood clots. As with any hormonal therapy, it’s important to monitor patients as treatment progresses. Men receiving hormone replacement therapy are seen for blood tests and a prostate exam at one, three and six months after beginning treatment. They continue to be seen every six months.

Other treatments may include:

Erectile dysfunction (ED) therapy — referral to a Medical College of Wisconsin urologist for treatment if ED is not caused by a hormonal disorder
Bone loss treatment, if bone loss has been diagnosed
Gynecomastia treatment, if desired, which may involve breast reduction surgery

Causes of Hypogonadism

Froedtert & The Medical College of Wisconsin endocrinologists are experts in identifying and treating all forms of male hypogonadism.

Causes of primary hypogonadism (testicular dysfunction)