TSH is thyroid stimulating hormone; it is secreted by the pituitary gland in the brain. The function of TSH is to regulate the amount of thyroid hormone T3 (triiodothyronine) and T4 (thyroxin) in the blood for various metabolic activities, growth and development.
What Is TSH 3rd Generation?
- The thyroid hormone T3 and T4 are secreted by the thyroid gland. Thyroid gland is a butterfly shaped gland located in the center of the lower neck below the voice box.
- Thyroid disorders such as hypothyroidism or hyperthyroidism can be detected by testing T3, T4, and TSH in the blood. TSH plays a vital role in producing thyroid hormone and its regulation, therefore TSH blood estimation in thyroid disorder is very significant.
- 3rd generation TSH is a laboratory test which can measure the TSH level even when it is at a very low concentration in the blood. This is where it differs from first and second generation tests.
Thyroid Stimulating Hormone Normal Range
- The normal range of TSH 3rd generation is 0.3 to 3mlU/L according to American Association of clinical Endocrinologists. The earlier normal range first and second generations were considered between 0.5 to 5. 0mlU/L.
- According to TSH 3rd generation test, TSH below 0.3mlU/L indicates hyperthyroidism, whereas TSH level above 3mlU/L indicates hypothyroidism.
3rd Generation TSH Levels
Due to its sensitivity of measuring TSH at a very low concentration, TSH 3rd generation blood test is considered to be more accurate by physicians for diagnosing thyroid disorders. It is also useful in adjusting the thyroid medicinal dose in a hypo or hyper thyroid patient.