Thyroid stimulating hormone is referred to as TSH. A blood test called a TSH test is used to assess this hormone. TSH readings that are abnormally high or low might indicate a thyroid issue.
The thyroid is a little gland at the front of your neck that resembles a butterfly. The hormones your thyroid produces regulate how your body utilizes energy. The thyroid hormones, including your heart, impact nearly every organ in your body. They support the regulation of your mood, muscular tone, weight, and body temperature. Numerous bodily processes slow down if your blood doesn’t have adequate thyroid hormones. When you have too much, several physical processes accelerate.
The pituitary gland, a gland located in the brain, regulates your thyroid. The pituitary gland produces the thyroid-stimulating hormone (TSH). TSH informs your thyroid of the necessary production rate for thyroid hormone.
Your pituitary gland produces more TSH to instruct your thyroid to work harder if the thyroid hormone levels in your blood are too low. If your thyroid hormone levels are too high, the pituitary gland produces little or no TSH. You can determine whether your thyroid has the appropriate amount of hormones by checking the TSH levels in your blood.
Why is it done?
A TSH test is utilized to determine how well your thyroid is functioning. It may determine if your blood has hyperthyroidism (excess thyroid hormone) or hypothyroidism (insufficient thyroid hormone). However, a TSH test cannot identify the root cause of a thyroid condition.
You’ll have routine TSH testing to monitor your thyroid hormone levels if you use prescription thyroid hormone medication due to hypothyroidism or because your thyroid was removed. After receiving medication for hyperthyroidism, TSH testing is often used to monitor your thyroid hormone levels.
Is a TSH test necessary, and why?
If you have signs of having too much or too little thyroid hormone in your blood, a TSH test may be necessary.
Overactive thyroid is another name for hyperthyroidism (too much thyroid hormone). When you have more thyroid hormones than you need, your body works faster and exhibits signs like:
- Even though you can be eating more than usual, you nevertheless lose weight
- Irregular or fast pulse
- Feeling uneasy or agitated
- Difficulty sleeping and weariness
- Hand trembling and muscle wasting
- Sweating or having extreme heat sensitivity
- Regular bowel movements (a lot of pooping)
- Goiter (An enlarged thyroid)
Underactive thyroid is another name for hypothyroidism (too little thyroid hormone). Your body’s activities are slowed down by low thyroid hormone levels, which may result in symptoms like:
- Fatigue
- Gaining weight
- Being very susceptible to cold
- Muscle and joint discomfort
- Dry skin
- Thinning, dry hair
- Heavy or erratic menstrual cycles
- Depression
- Constipation
In addition to other testing, you could have a TSH test to help identify any odd lumps or bumps on your thyroid that might be thyroid cancer or thyroid nodules, which are benign growths on your thyroid.
What occurs during a TSH test?
A medical practitioner will use a tiny needle to draw blood from a vein in your arm. A small quantity of blood will be collected into a test tube or vial once the hand has been placed. The needle may hurt somewhat when it enters or exits your body. Usually, this takes a few minutes.
Will I need to do anything to be ready for the test?
A TSH blood test does not need any particular preparation on your part. If your doctor has prescribed additional blood tests, you may need to fast (not eat or drink) for a few hours before the test. Your provider will let you know if there are any particular instructions to follow.
Does the test include any risks?
The danger of getting a blood test is relatively low. Even though you can have some little discomfort or bruising where the needle was inserted, most side effects are transient.
What do the findings indicate?
Your TSH test results might let you know if your thyroid is producing too much or too little thyroid. Your TSH levels may be too high or too low, but the test cannot diagnose why.
If your test results are abnormal, your doctor will likely request more thyroid blood tests to identify the root of your thyroid issue. These blood tests might consist of the following:
- Test for thyroid hormone T4
- Test for thyroid hormone T3
- Tests for thyroid antibodies may help identify autoimmune thyroid disorders like:
- The most typical cause of hyperthyroidism is Graves’ disease.
- The most frequent cause of hypothyroidism is Hashimoto’s disease.
- An abnormal TSH test may sometimes indicate a pituitary gland issue, although this is uncommon.
Study up on laboratory procedures, reference intervals, and reading findings.
Do I need to learn anything more about a TSH test?
Even when your thyroid gland is healthy, your TSH levels might be high or low. Severe conditions unrelated to your thyroid may temporarily drop your TSH levels. And even if they have no thyroid issues, folks over 80 may have greater TSH levels.
TSH levels are also impacted by pregnancy. The first three months are often a touch low. However, thyroid illness might sometimes manifest during pregnancy. Your doctor will keep an eye on your health during your pregnancy and after your child’s birth if you acquire thyroid illness while you are expecting. This is due to the possibility of hyperthyroidism and, less often, hypothyroidism, persisting after giving birth. If you are pregnant or want to become pregnant and have a history of thyroid problems, be careful to discuss this with your healthcare practitioner.
A TSH test is often performed on newborn infants to check for congenital hypothyroidism, which is hypothyroidism that exists from birth.