What does it mean if your tsh is too high

what is thyroid stimulating hormone (tsh)?

thyroid-stimulating hormone, commonly called tsh and also known as thyrotropin, is a hormone released by the pituitary gland to cause the thyroid to make and release its own hormones: thyroxine (t4) and triiodothyronine (t3). These two hormones are essential for maintaining your body’s metabolic rate—the rate at which your body turns the food you eat into energy and uses it. thyroxine and triiodothyronine also maintain:

• your heart and digestive functions.
• muscle control.
• brain development.
• bone maintenance.

Hormones are chemicals that coordinate different functions in your body by carrying messages through your blood to your organs, muscles, and other tissues. these signals tell your body what to do and when to do it.

Your pituitary gland is a small, pea-sized gland located at the base of your brain below your hypothalamus. produces and releases eight hormones, including tsh. Your pituitary gland consists of two lobes: the posterior (back) lobe and the anterior (front) lobe. the anterior lobe produces tsh.

The thyroid is a small, butterfly-shaped gland located in the front of the neck under the skin. your pituitary gland and thyroid are part of your endocrine system.

how are tsh levels monitored?

multiple hormones and glands in your endocrine system work together to carefully control the level of tsh in your bloodstream through a feedback loop.

To begin with, the hypothalamus releases thyroid-releasing hormone (trh) to trigger the release of thyroid-stimulating hormone (tsh) from the pituitary gland.

Your pituitary gland is connected to your hypothalamus through a stalk of blood vessels and nerves. this is called the pituitary stalk. Your hypothalamus is the part of your brain that controls functions like blood pressure, heart rate, body temperature, and digestion. Through the stalk, your hypothalamus communicates with your pituitary gland, telling it to release certain hormones. In this case, your hypothalamus releases thyroid-releasing hormone (TRH), which stimulates your anterior pituitary lobe to release TSH. your hypothalamus may also release somatostatin, another hormone, to inhibit (prevent) the release of tsh from your anterior pituitary.

tsh then stimulates thyroid cells to release thyroxine or t4 (80%) and triiodothyronine or t3 (20%) into the bloodstream. These two hormones prevent the pituitary gland from producing more TSH if thyroxine and triiodothyronine levels are too high, thus completing the cycle. when t4 and t3 levels drop, the cycle starts again.

Because of this feedback loop, if your thyroid produces too much or too little thyroid hormone, it affects your tsh levels. Also, if your pituitary gland produces too much or too little TSH, it affects your thyroid function. it is more common to have a problem with the thyroid that causes irregular tsh levels than to have a problem with the pituitary gland that causes irregular tsh levels.

what are normal tsh levels?

Normal tsh levels vary by age. In general, normal tsh ranges for healthy people who are not pregnant include:

• Infants up to 5 days old: 0.7 – 15.2 micro international units per milliliter (iu/ml).
• babies from 6 to 90 days: 0.72 – 11.0 iu/ml.
• babies from 4 to 12 months: 0.73 – 8.35 iu/ml.
• children from 1 to 6 years old: 0.7 – 5.97 iu/ml.
• children from 7 to 11 years old: 0.6 – 4.84 iu/ml.
• people from 12 to 20 years old: 0.51 – 4.3 iu/ml.
• adults from 21 to 99 years old: 0.27 – 4.2 iu/ml.

Normal value ranges for tsh may vary slightly between different laboratories. be sure to check your lab report’s reference range on your results. If you have any questions about your results, ask your healthcare provider.

what are normal tsh levels during pregnancy?

It is especially important for pregnant women to have healthy amounts of TSH and thyroid hormones to ensure the healthy development of their babies. TSH levels fluctuate during pregnancy. In general, normal tsh levels during pregnancy include:

• first trimester (9 to 12 weeks): 0.18 – 2.99 (uiu/ml).
• second trimester: 0.11 – 3.98 iu/ml.
• third trimester: 0.48 – 4.71 iu/ml.

Always check your lab’s reference range on your results report. If you have questions about your results, ask your healthcare provider.

how are tsh levels tested?

Health care providers test TSH levels using a blood test. They take a blood sample from a vein in your arm and send the sample to a lab for testing. You usually don’t need to do anything special to prepare for a TSH blood test.

a tsh blood test is often the first test providers order if you experience symptoms related to thyroid problems.

what happens when tsh levels are too low?

If you have too little tsh, your thyroid gland is most likely making too much thyroid hormone. this condition is called hyperthyroidism or overactive thyroid. A variety of conditions lead to hyperthyroidism, including Graves’ disease and thyroid nodules. Just over 1% of adults in the United States have hyperthyroidism.

Because thyroid hormone suppresses the release of tsh, high levels of thyroid hormone can cause lower than normal tsh levels. Rarely, problems with the pituitary gland, such as a nonfunctioning pituitary adenoma, can lead to low tsh and low thyroid hormone levels.

symptoms of low tsh levels

Low tsh levels are often a sign of hyperthyroidism. symptoms of hyperthyroidism include:

• rapid heartbeat (palpitations).
• feel shaky and/or anxious.
• unexplained weight loss with increased appetite.
• diarrhea and more frequent bowel movements.
• vision changes and/or bulging eyes.
• thin, warm, moist skin.
• swelling and enlargement of the neck due to an enlarged thyroid gland (goiter).
• irregular menstrual periods.

If you experience these symptoms, it is important to talk with your healthcare provider. hyperthyroidism is treatable.

what happens when tsh levels are too high?

If you have too much tsh, it may mean that your thyroid is not making enough thyroid hormone. this condition is called hypothyroidism or underactive thyroid. Various conditions can cause hypothyroidism, including Hashimoto’s disease. About 5% of adults in the United States have hypothyroidism.

Because thyroid hormone suppresses the release of tsh, too little thyroid hormone can cause the pituitary to make too much tsh. Rarely, problems with the pituitary gland, such as a tsh-secreting pituitary adenoma, or rare genetic conditions can result in higher than normal levels of thyroid hormone and tsh.

symptoms of high tsh levels

high levels of tsh are usually a sign of hypothyroidism. Symptoms of hypothyroidism include:

• fatigue.
• numbness and tingling in the hands.
• constipation.
• unexplained weight gain.
• depression.
• not able to tolerate low temperatures.
• decreased interest in sex.
• frequent and heavy menstrual periods.

It is important to talk to your healthcare provider if you experience these symptoms. hypothyroidism is treatable.

Should I be concerned if my tsh level test results are abnormal?

If your tsh test results are abnormal, it doesn’t always mean you have a medical condition. Your healthcare provider will consider many factors when interpreting your tsh test results, including:

• your age: Tsh levels tend to be higher in people over 80 years of age. Most older people with slightly higher than normal tsh levels do not have any associated health conditions.
• pregnancy: Pregnancy causes changes in thyroid hormones. it’s common for tsh to be a little lower than normal during the first trimester and then slowly rise.
• severe illness: People who are very sick with conditions that are not related to the thyroid may have a temporary low tsh level.
• Other thyroid tests: The results of other thyroid tests, such as free t4 and thyroid antibodies, may affect how your provider interprets your thyroid test results. tsh test.

a note from the cleveland clinic

In most cases, irregular levels of thyroid-stimulating hormone (tsh) mean there’s a problem with your thyroid—it’s making too much or too little thyroid hormone. The good news is that thyroid hormone levels and TSH levels can be corrected with treatment and medication. If you have any questions about your tsh test results, talk to your health care provider. they are there to help.