Free Testosterone Test

This test measures the Free Testosterone levels in the blood.

What is Testosterone?

Luteinizing Hormone LH is a pituitary hormone that stimulates and controls the production of testosterone hormone. Secretion of Testosterone into the blood circulation depends on the response of Luteinizing Hormone (LH). Most of the Testosterone which is secreted into the blood binds to the Sex-hormone binding globulin (SHBG) and a little amount to the albumin. The remaining amount of testosterone which is not bounded and freely circulates in the blood is known as Free Testosterone. Free testosterone and testosterone bound to albumin together is the bioavailable testosterone. It is present in both male and female.

This hormone is responsible for male physical characteristics and known as a male sex hormone. This is mainly produced by the Leydig cells which are present in the male testicles. Luteinizing Hormone helps testicles to produce testosterone. In women, testosterone is produced in less amount by ovaries. It is also produced by adrenal glands in both men and women.

Testosterone plays an important role in the facilitation of spermatogenesis (production of sperm). Testosterone stimulates the development of secondary sexual characteristics in men like the growth of the body hair, deepening of the voice, enlargement of the penis (sex organ in men), muscle development. In women, testosterone is converted to the main female sex hormone i.e:-Estradiol. Testosterone production is high in the early morning hours from about 4-am to 8-am and low in production from about 4-pm to 8-pm. Production of testosterone is rapidly high at the onset of puberty and starts to drop at the age near to 30.

Why this test is performed?

The free Testosterone test is performed to understand whether the testicular function in men is normal or abnormal. This test is performed to diagnose hypogonadism, hypopituitarism, impotence, and Klinefelter syndrome, erectile dysfunction, testicular tumors, hypothalamus or pituitary gland disorder in men. It also helps to investigate the cause of unwanted hair growth, anovulation, tumors of the ovary, amenorrhea, and virilization in women.

Your doctor may ask you to perform this test if you are suffering from symptoms like underdevelopment of muscle in puberty, lack of body hair, enlarged breasts, low energy levels, slow growth of hair, hair loss, loss of bone mass, underdeveloped male genitals (penis), irregular or missed periods, unusual body hair growth in women, or heavy vaginal bleeding. Your doctor may advise you to perform this test if you are suffering from infertility. This test is also being performed to estimate the effectiveness of the treatment and testosterone levels in the body. If you exhibit any symptoms of testicular dysfunction, your doctor may ask you to undergo a Free Testosterone test which gives a better status of the condition. Mostly, this test is done along with other testosterone tests.

Precautions:

Smoking, chemotherapy, and radiation may change the levels of Free Testosterone in the blood. So inform your doctor prior to the test if you are on to these.

If the test result falls within the normal reference range, then no need for further medical intervention.

In case of increased Free Testosterone in the blood than the normal range then it may be due to early puberty in young men, acne, high libido (hypersexuality), infertility (not getting pregnant), steroid abuse, tumors in testes, decreased sperm count, high blood pressure, high red blood cell count, aggression, treatment with testosterone medications, or polycystic ovarian syndrome.

If the level of Free Testosterone is less than the normal range then it may be due to hypogonadism, testicular failure, pituitary disorders, Klinefelter syndrome (a genetic disorder), obesity, adrenal cancer, ovarian cancer, high levels of stress, or major surgery.