Can TSH test detect pregnancy?

Not usually. Tsh or thyroid-stimulating hormone, is made by pituitary gland to control thyroid hormone production by thyroid gland. Tsh level is useful to detect over- or under-active thyroid levels, as well as to guide thyroid treatment doses. In a woman with known hypothyroidism, onset of pregnancy will raise the TSH higher, indicating need for higher thyroid doses. But TSH is not direct test for pregnancy.