Testosterone

The testosterone test measures the amount of testosterone, the male hormone, in the blood. However, this hormone is produced by both men and women.

This testosterone test measures the total amount of testosterone found in the blood. A large amount of the testosterone in the blood is bound to a protein called sex hormone binding globulin (SHBG). But another test which measures only the free testosterone in the blood is available. This test for free testosterone isn’t always accurate.

How is a testosterone test done?

A healthcare provider will take a blood sample from your vein. The best time for collecting the blood sample is from 7a.m to 10 a.m. You might need a second sample collection to confirm the result if the initial result was lower than expected.

How to prepare for a testosterone test

Your healthcare provider may advise that you stop taking certain medications that may affect the test result.

How will the test feel?

When the provider inserts the needle, you may feel a slight sting or prick. Some people also feel a throbbing afterwards.

Why perform a testosterone test?

The healthcare provider may order this test if you have abnormal androgen (male hormone) production symptoms.

The testicles produce the largest amount of testosterone in males. The test is usually to evaluate the following signs of abnormal testosterone. These signs include:

• Infertility, low sex drive, thinning of the bones and erectile dysfunction in men
• Late or early puberty in boys

The ovaries produce testosterone in females. However, the adrenal glands can also produce an excess of other androgens, which get converted to testosterone. The levels are mostly checked to evaluate the signs of elevated testosterone levels, such as:

• Hair thinning or male-pattern baldness
• Acne, oily skin
• Increased size of the clitoris
• Change in voice
• Excess hair growth (dark, coarse hair in the inner thighs, chest, buttocks, beard, moustache, beard sideburns)
• Decreased breast size
• Absent or irregular periods

Normal results

The normal measurements for the testosterone test are:

• Male: 10 – 35 nanomoles per litre (nmol/L) or 300 – 1000 nanograms per decilitre (ng/dL)
• Female:5 – 2.4 nmol/L or 15 – 70 ng/Dl

The above values are common measurements for testosterone tests, but the normal value may differ slightly in laboratories. Some labs also use different measurements or use different test specimens. Ensure you consult your provider about the meaning of your test result.

What do abnormal results mean?

Some medicines, health conditions or injuries can cause low testosterone levels, and your testosterone levels will naturally drop with age. In men, low testosterone levels may affect muscle mass, mood and sex drive.

Low total testosterone levels may result from

• Chronic illness
• Excess body fat (obesity)
• Low thyroid function
• Problems with the hypothalamus, the area of the brain that controls hormones
• The pituitary gland not producing the normal amount of all or some of its hormones
• Delayed puberty
• Sleep problems like obstructive sleep apnoea
• Chronic stress from too much exercise, also called over-training syndrome
• Benign tumour of the pituitary cells that produce excess prolactin
• Diseases of the testicles, such as cancer, infection, iron overload and trauma

Higher total testosterone levels may result from

• Congenital adrenal hyperplasia
• Ovarian tumour
• Resistance to action of the male hormone (androgen resistance)
• Taking drugs or supplements that increase testosterone levels
• Testicular cancer

At our clinic, we offer testosterone test and other hormone tests. You can call us on 02071830244 to book an appointment for your testosterone test.