Hormone Testing in the Lab
Growth hormone and testosterone tests are required to determine the exact levels of these hormones in the blood and learn if a patient has got a deficiency and whether he or she requires treatment.
Growth Hormone Tests
Growth hormone (GH) tests are blood tests that check to see if your body is making a normal amount of GH. GH, also known as human growth hormone, is a substance that controls your body’s growth. It also helps control metabolism, the process of how your body uses food and energy. GH is made in the pituitary gland, a small organ at the base of the brain.
In children, GH plays a major role in bone growth, development of muscle mass, and height. In adults, GH affects bone and muscle health. If children or adults have too much or too little GH, it can cause health problems.
GH levels in the blood fluctuate throughout the day depending on your diet and activity levels. So, a standard blood test doesn’t usually provide helpful information about GH levels. Instead, GH levels are usually checked in tests that measure other substances, such as hormones and proteins, that are related to GH production.
Other names: GH test, human growth hormone test, somatropin test, growth hormone stimulation test, growth hormone suppression test.
What are they used for?
GH tests are used to diagnose GH disorders, including:
- GH deficiency. In children, GH is essential for normal growth and development. A GH deficiency can cause a child to grow more slowly and be much shorter than children of the same age. In adults, GH deficiency can lead to low bone density and reduced muscle mass.
- Gigantism. This is a rare childhood disorder that causes the body to produce too much GH. Children with gigantism are very tall for their age and have large hands and feet.
- Acromegaly. This disorder, which affects adults, causes the body to produce too much growth hormone. Adults with acromegaly have thicker than normal bones and enlarged hands, feet, and facial features.
The tests may also be used if other tests show a problem with the pituitary gland.
Why do I need a growth hormone test?
Your provider may order a GH test if you or your child has symptoms of a GH disorder.
Symptoms of GH deficiency in children include:
- the slowed growth rate compared with children of the same age;
- shorter height, arms, and legs, and lower weight than children of the same age;
- small penis in males;
- delayed puberty.
Adults with GH deficiency may have symptoms such as fatigue and decreased bone density and muscle mass. But GH testing isn’t common for adults, as other disorders are much more likely to cause these symptoms.
Symptoms of GH excess (gigantism) in children include:
- excessive growth compared with children of the same age;
- overly large head;
- larger than normal hands and feet;
- mild to moderate obesity.
Symptoms of GH excess (acromegaly) in adults include:
- a deep, husky voice;
- larger than normal facial features such as lips, nose, and tongue;
- excessive sweating and body odor;
- thickening of bones;
- coarse, oily skin;
- irregular menstrual cycles in women;
- erectile dysfunction in men.
What happens during a growth hormone test?
Your provider may order a GH stimulation or a GH suppression test, depending on whether symptoms show a possible GH deficiency (not enough GH) or a GH excess (too much GH).
A GH stimulation test is used to check for a GH deficiency. During the test:
- A health care professional will take a blood sample from a vein in your arm, using a small needle.
- After the needle is inserted, a small amount of blood will be collected into a test tube or vial.
- Your child (or you) will be given a medicine through an IV line that stimulates the pituitary gland to make GH.
- More blood samples will be taken over the course of about two hours.
- Each sample will be tested to see if GH levels have increased.
A GH suppression test is used to check for a GH excess. During the test:
- A health care professional will take a blood sample from a vein in your arm, using a small needle.
- After the needle is inserted, a small amount of blood will be collected into a test tube or vial.
- You or your child will drink a solution that contains water and glucose (sugar).
- Two more blood samples will be taken within one to two hours after drinking the solution.
- The blood samples will be tested to see if GH levels have decreased.
Will I need to do anything to prepare for this test?
You may need to fast (not eat or drink) for several hours before your test.
Are there any risks to this test?
There is very little risk to you or your child is having a blood test or getting an IV. There may be slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly. There is no risk in drinking the glucose solution.
What do the results mean?
If GH levels don’t increase to a certain level during a GH stimulation test, it may indicate GH deficiency.
If your child is diagnosed with GH deficiency, he or she may benefit from treatment with GH supplementation. GH supplementation is an injected medicine that contains manufactured human growth hormone. When GH deficiency is diagnosed and treated early, some children can grow several inches in the first year of treatment. Others grow less and more slowly but still benefit from treatment.
If GH levels don’t decrease to a certain level during a GH suppression test, it may mean your child has gigantism or you have acromegaly.
Gigantism and acromegaly are most often caused by a tumor in the pituitary gland, a small organ in the base of the brain that controls many functions, including growth. Treatment for the tumor may include radiation therapy, surgery, and/or medicine. If the disorders were not caused by a tumor, you or your child may need more tests.
Is there anything else I need to know about a growth hormone test?
Your provider may order other blood tests to help diagnose a GH disorder. These include:
- IGF-1 test. IGF-1 is a hormone that helps manage GH in the body. Unlike GH, IGF-1 levels remain stable throughout the day. So, it can be a useful way to find out if your body is making a normal amount of GH.
- IGBP-3 test. IGBP-3 is a protein that is the main carrier of IGF-1. This test can help diagnose a GH deficiency or GH excess.
Testosterone test
The hormone testosterone (T) is often associated with masculinity. But women’s bodies also make testosterone. Too little or too much testosterone in men or women can indicate serious health problems.
In men, the testicles make testosterone. In women, the ovaries produce the hormone.
Testosterone is responsible for traits such as:
- body hair;
- muscle mass;
- strength.
Men with low levels of testosterone might notice a reduction in these traits, while women with too much testosterone might notice an increase in these traits.
You may want to take a testosterone level test if you believe your testosterone levels are not within a normal range.
When to get tested: Understanding testosterone levels
A normal range for testosterone level in men is 300 to 1,000 nanograms per deciliter (ng/dL). For women, it’s between 15 and 70 ng/dL. However, it’s also considered normal to have changes in your level of testosterone throughout your life.
Testosterone levels can decrease naturally due to your age or other health conditions.
After age 30, men’s testosterone levels can decrease an average of up to 2 percent every year. Some symptoms of low testosterone, particularly erectile dysfunction, are commonly seen in men over age 30. Low testosterone levels have often been observed in people with obesity, no matter their age.
The most common testosterone-related problem in men is hypogonadism, also called low testosterone. To be diagnosed with hypogonadism, a person must not only have low testosterone levels but also experience symptoms of low testosterone.
Symptoms of low testosterone
Your testosterone level may be abnormally low if you have one or more of the following symptoms:
- decreased sex drive;
- inability to achieve an erection (erectile dysfunction);
- inability to conceive a child;
- overall tiredness.
Symptoms of high testosterone
Women with too much testosterone may grow facial hair, develop a deeper voice, or experience decreased breast size. Too much testosterone in women can also cause acne.
One possible cause of too much testosterone in women is polycystic ovary syndrome (PCOS). PCOS can make it difficult to get pregnant and interfere with menstruation.
What if I’m experiencing symptoms?
Abnormally high or low levels of testosterone in men and women can indicate other serious conditions.
High T levels can indicate ovarian or testicular cancer. Low T levels can indicate chronic illness or a problem with the pituitary gland, which releases hormones.
In infant boys and girls, signs of abnormal testosterone levels may be more extreme. Testosterone tests are often ordered for boys and girls who are not developing properly or when parents notice delayed puberty.
Boys with low T may grow slowly, with no body hair and poorly developed muscles. Girls with high T may have delayed menstruation or too much body hair. Boys with high T may enter puberty early and robustly.
Too much T: Congenital adrenal hyperplasia
Sometimes, too much T is the result of a condition known as congenital adrenal hyperplasia (CAH). This testosterone overload can result in males having an abnormally large penis and females having abnormal genitalia at birth.
In some cases, CAH can cause men to have a very deep voice and women to grow facial hair.
CAH can be diagnosed early in infants because it causes dehydration, poor feeding habits, and other symptoms. It can also cause stunted growth, even though someone with this condition may be tall when they’re young.
How is a testosterone test performed?
Getting testosterone levels checked usually requires a blood test. The test is usually performed in the morning when T levels are highest. Sometimes, the test needs to be retaken to confirm the measurements.
Before the test, a doctor may ask you to stop taking any prescriptions that could affect your testosterone levels. Some medications that can artificially increase your testosterone levels include:
- steroids (but T levels can fall rapidly after stopping them);
- barbiturates;
- anticonvulsants;
- androgen or estrogen therapies.
Some medications, including opiates, can artificially decrease your testosterone levels. If you’re taking any of the medications above, tell a doctor. They’ll ensure that your testosterone test results are accurate.
Depending on your symptoms, a doctor may also perform a physical examination. If you’re male, a doctor may perform a physical if they notice:
- a loss of facial hair;
- a loss of height;
- signs of gynecomastia, an abnormal increase in breast tissue size;
- abnormal weight gain.
If you’re female, a doctor may perform a physical if they notice:
- abnormal facial acne;
- abnormal hair growth on your lips or chin (hirsutism);
- abnormal hair thinning or balding on the head.
Testosterone home testing kits are widely available from several companies. They use your blood or saliva to test your hormone levels. After taking the test, you’ll send your sample to a laboratory for testing.
Several studies have confirmed that saliva offers a relatively accurate measurement of testosterone levels and should continue to be clinically tested to confirm that saliva samples are a reliable replacement for blood samples.
Some research suggests salivary testing is not fully reliable, though. It suggests that supplemental tests, such as serum testing, are necessary to ensure that salivary test results are accurate.
How can I treat my abnormal testosterone levels?
Ask a doctor about testosterone tests if you suspect that you have abnormal hormone levels or if you notice developmental issues in your children. A wide range of treatments is available.
Some treatments include testosterone pellet implants and a recently FDA-approved oral testosterone supplement.
The most common treatment for low testosterone is testosterone replacement therapy (TRT). TRT is given as an injection, a skin patch, or a topical gel containing testosterone that replaces the testosterone missing from your body.
Though this treatment is common, TRT is known to have some risks and side effects. They include:
- sleep apnea;
- acne;
- blood clot formation;
- possible worsening of benign prostatic hyperplasia, or prostate growth;
- possible increased risk of heart attacks and strokes.
If you’re taking any medications or supplements (such as steroids) that abnormally affect your testosterone levels, a doctor may ask you to stop taking them or suggest an alternative.
A doctor may also recommend lifestyle changes, such as exercising to build muscle and healthy weight loss through dietary changes, depending on your specific situation, that can help balance your testosterone levels.
Ask any other questions concerning growth hormone and testosterone levels testing from our qualified experts, get in touch here.