The TSH 3rd generation test is a diagnostic blood test that measures the amount of thyroid-stimulating hormone in the blood stream. The test is used to evaluate thyroid function and to determine if hypothyroidism or hyperthyroidism is present.
The TSH 3rd generation test is very sensitive and detects even minute amounts of circulating hormones. The test is also used to diagnose endocrine and infertility conditions in women, and as a monitoring tool for those taking thyroid replacement hormones. Dosing for thyroid replacement hormone therapy is typically based upon the results of the TSH test. An elevated TSH 3rd generation test indicates hypothyroidism, and a decreased value indicates hyperthyroidism. While considered an accurate diagnostic test, results may be skewed by taking thyroid supplements.