Testosterone Test
Testosterone is a steroid hormone, which is found in both males and females; men have around ten times more testosterone than women. Testosterone has a number of important roles, particularly in men; testosterone stimulates puberty, sexual development and helps to control the formation of muscle mass and regulate sex drive. The production of testosterone is regulated by luteinising hormone (LH), which is produced by the pituitary gland.
Why is the test used?
The test is used to assess the level of testosterone in the body; if levels are too high or too low, this can cause health conditions and problems. For men, the testosterone test may be ordered if the patient is suffering from erectile dysfunction, infertility and decreased libido. In female patients, the test may be used if the patient has excessive hair growth (hirsutism), infertility or virilisation (this is the development of male characteristics); the test may also be used if a doctor suspects that a patient may have an ovarian tumour. The test may also be used for patients of both sexes if the doctor suspects an adrenal tumour or problems relating to the hypothalamus or pituitary gland.
The test may also be used if young boys appear to be going through puberty very early or very late.
How is the test done?
The test is done by taking a sample of blood from the patient’s arm; a needle is inserted into the vein and the blood is drawn out into a syringe. Once the sample has been collected, it will be bottled, labelled and sent off to the laboratory for analysis.
The test is usually carried out early in the morning, as levels of testosterone in males are usually highest at this time; levels decrease throughout the day and are lowest in the evening.
What do the test results mean?
Levels of testosterone usually decrease as a man gets older.
Low levels of testosterone may be associated with problems which affect the pituitary gland or damage to the testes. Certain inherited conditions, including Prader-Willi syndrome, can also affect the production of testosterone. Injuries, excessive drinking and viral infections, such as mumps, can also affect production of testosterone by the testes.
Increased testosterone levels in men may indicate that the patient has a testicular tumour and further tests will be ordered; in young males, a high level of testosterone usually indicates early puberty.
Increased levels of testosterone in females may indicate that the patient has a health condition, such as PCOS (polycystic ovarian syndrome) or ovarian cancer.
Certain medications including steroids and androgens and alcohol decrease testosterone levels.
Specific Blood Tests
- Specific Blood Tests
- Factor V Leiden Mutation and PT 20210 Mutation
- Ferritin Test
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- Electrolytes
- Epstein-Barr Virus Antibodies
- Erythrocyte Sedimentation Rate
- Erythropoietin
- Ethanol
Blood Test Guide
- Blood Tests
- Types of blood tests
- what to expect
- What are the risks of blood tests?
- What do blood tests show?
- Specific Blood Tests