TSH test normal levels

 TSH is thyroid stimulating hormone and produced in pituitary gland. TSH travels to thyroid gland after released from pituitary gland  then stimulates thyroid gland for thyroid hormones T3 and T4 production.

TSH normal range should be known for TSH blood test evaluation. Different units and ranges may be used in several labs so TSH test result must be evaluated by using the lab’s normal ranges and units that you have the test.

Where the TSH is  produced in body

TSH- thyroid stimulating hormone is produced in pituitary gland in your brain. TSH stimulates your thyroid gland for T3- triiodothyronine and T4-thyroxine thyroid hormones production.

TSH test purpose


TSH blood test is used to determine how well your thyroid gland is working. TSH blood test provides information about thyroid gland problems, thyroid disorder treatment, overactive thyroid gland and underactive thyroid gland.

Evaluation of TSH blood test


TSH normal range of lab should be known for TSH test evaluation. Reference range of TSH and normal levels change according to test method, lab, analyzer, and the units that are used in lab. mIU/L ( milli-internation unit per liter) is the unit which is commonly used by labs for TSH test results.

TSH blood test normal levels

Adult 0.3-4.2 mIU/L
11-19 years 0.5-4.3 mIU/L
6-10 years 0.6-4.8  mIU/L
1-5 years 0.7-6.0 mIU/L
3-11 months 0.7-8.4 mIU/L
6 days-2 months 0.7-11.0 mIU/L
Newborn- 5 days baby 0.7-15.2 mIU/L

( TSH test results are taken from Mayo Clinic web page )


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