How is it used?
Testosterone testing is used to diagnose several conditions in men, women, and boys. These conditions include:
Boys
delayed or early (precocious) puberty
Men
decreased sex drive
erectile dysfunction
infertility
Women
infertility
excessive body hair, also called hirsutism
virilization
ovarian tumours
Men and women
adrenal tumours
Hypothalamic and pituitary disorders
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When is it requested?
In boys, the testosterone is measured with the
FSH and
LH tests, if puberty is delayed or slow in developing. Although puberty begins at different times in different individuals, generally by the age of 10 years, there are hormonal and physical manifestations of the onset of puberty. A delay can occur if the testes do not produce enough testosterone or if the pituitary does not produce enough LH.
The test may be performed if a young boy seems to be undergoing a very early (precocious) puberty with obvious secondary sex characteristics, such as an enlarged penis, development of muscle mass, deepening voice and growth of body hair.
In men, the test may be performed when
infertility is suspected or if the patient has a decreased sex drive or erectile dysfunction, which can result from low testosterone levels.
In women, testosterone may be measured if a patient has irregular or no menstrual periods (amenorrhoea), is having difficulty getting pregnant, or appears to have masculine features, such as facial and body hair, male pattern baldness, and a low voice. Testosterone levels can rise because of tumours that develop in either the ovary or adrenal gland or because of other conditions, such as
polycystic ovarian syndrome (PCOS).
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What does the test result mean?
There is great variability in testosterone levels in men and it is normal for testosterone levels to fall as men get older.
In males, a low testosterone level may be due to hypothalamic or pituitary disease with reduced production of LH and FSH, or damage to the testes with reduced production of testosterone. Genetic diseases can cause decreased testosterone production in young men (Klinefelter’s, Kallman’s, and Prader-Willi syndromes) or testicular failure and
infertility (as in myotonic dystrophy, a form of muscular dystrophy). A decreased testosterone level also can indicate impaired testosterone production because of acquired damage to the testes, such as
alcoholism, physical injury, or viral diseases like mumps.
Use of most anabolic steroids also causes a decrease in testosterone levels.
Increased testosterone levels in males can indicate
testicular tumours . Increased testosterone in boys is usually the cause of early puberty.
In women, increased testosterone levels can indicate
polycystic ovary syndrome (PCOS) or an ovarian or adrenal gland tumour.
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Is there anything else I should know?
Alcoholism and
liver disease in males can decrease testosterone levels. Drugs, including androgens and steroids, can also reduce testosterone levels.
Prostate cancer responds to androgens, so men with advanced prostate cancer may receive drugs that lower testosterone levels.
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