Normal Values of Thyroid-Stimulating Hormone (TSH)
May 10, 2022
Source: Cainiu Health
Dr. Pan Yongyuan
Introduction
Thyroid-stimulating hormone (TSH): For individuals over 18 years of age, the normal reference range is 0.55–4.78 µIU/mL; for children aged 2–12 years, the normal range is 0.64–6.27 µIU/mL. The normal reference ranges for thyroid hormones and TSH should be based on those provided by the local hospital where the blood sample was drawn.
Thyroid-stimulating hormone (TSH) is a glycoprotein hormone primarily secreted by the anterior pituitary gland’s thyrotrophs (not eosinophils—this is an error in the original text). Both elevated and decreased TSH levels are abnormal and may indicate hypothyroidism or hyperthyroidism, respectively.
Normal Reference Range for Thyroid-Stimulating Hormone (TSH)
For individuals aged 18 years and older, the normal TSH range is 0.55–4.78 µIU/mL; for children aged 2–12 years, the normal range is 0.64–6.27 µIU/mL. However, the reference ranges for thyroid hormones (e.g., FT3, FT4) and TSH should be interpreted according to the specific laboratory’s reference values provided by the local hospital where the blood sample was drawn. This is because different hospitals use varying assay instruments and methodologies, leading to differences in reported normal ranges. These ranges are not directly comparable across laboratories; therefore, clinical interpretation must rely exclusively on the reference values supplied by the testing laboratory.
TSH is secreted by the anterior pituitary gland. Its secretion is regulated by two opposing mechanisms: it is stimulated by thyrotropin-releasing hormone (TRH) released from the hypothalamus, while simultaneously inhibited via negative feedback by circulating thyroid hormones (primarily T3 and T4). This dynamic interplay forms the hypothalamic–pituitary–thyroid (HPT) axis.
Thyroid hormones play a critical role in regulating thyroid follicular cell proliferation, thyroid blood supply, and the synthesis and secretion of thyroid hormones themselves—thereby maintaining normal thyroid function. We hope this information is helpful to you!
