Synonyms: Thyroid-stimulating hormone, thyrotrophin, thyrotrophic hormone
Related tests: thyroglobulin antibodies, FT3, FT4, thyroid peroxidase antibodies
Clinical significance
TSH is a hormone secreted by the anterior pituitary gland that stimulates all aspects of thyroid function, from iodine uptake to the release of the thyroid hormones T3 and T4 into the bloodstream. TSH secretion is stimulated by TRH, secreted by the hypothalamus, and inhibited by circulating thyroid hormones.
TSH is certainly the most appropriate test for screening thyroid function.
Clinical indications
Suspected thyroid dysfunction.
Sample type
The patient must have a blood sample taken.
Preparation
You must fast for at least 8 hours; a small amount of water is allowed. You must have been standing or sitting upright for at least 30 minutes.