In hypothyroidism, what typically happens to TSH levels?

In hypothyroidism, there is an underproduction of thyroid hormones (T3 and T4) due to insufficient stimulation of the thyroid gland, often resulting from issues such as autoimmune disorders (like Hashimoto's thyroiditis), surgical removal of the thyroid gland, or iodine deficiency. When the levels of thyroid hormones are low, the pituitary gland compensates by secreting more thyroid-stimulating hormone (TSH) to stimulate the thyroid gland to produce more hormones. This feedback mechanism is crucial for maintaining hormonal balance in the body.

Consequently, in the case of hypothyroidism, TSH levels increase as the body attempts to counteract the deficiency of thyroid hormones. This elevated level of TSH is a key indicator in diagnosing hypothyroidism.