The following are the indications to which prompt a free T4 and TSH test:
In a pregnant woman with known thyroid disease 4. How is the test performed?
A: A blood sample will be collected from a vein in your arm. Fasting is not needed prior to sample collection.
NORMAL VALUES OF TSH: 0.4 to 5.5mU/mL. If you are on thyroid medications then the value should be between 0.4 to 3.0 mU/mL.
Above-normal results mean—
If the TSH value is above the normal range, then it suggests that the thyroid gland is underactive (hypothyroidism) and the pituitary gland is releasing more TSH when thyroid is not capable of producing enough hormones.
Below normal results mean—
If the TSH value is below the normal range, then it suggests that the thyroid gland is overactive (hyperthyroidism) which suggests release of less TSH from pituitary as thyroid gland is over producing hormones.
Normal values of free T4: 0.7-1.9 ng/dL.