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TSH

Meaning

TSH, or Thyroid-Stimulating Hormone, is a critical regulatory hormone synthesized and secreted by the anterior pituitary gland that exerts primary control over the thyroid gland’s function. Measuring TSH levels is the most sensitive initial screening test for primary thyroid disorders, reflecting the pituitary’s feedback response to circulating thyroid hormone levels. A high TSH suggests primary hypothyroidism, while a low TSH often indicates hyperthyroidism.