Thyroid test results – healthy woman

The thyroid gland is a gland in the neck that is controlled by the pituitary gland. It produces hormones that help regulate important functions such as:

• temperature

• digestion

• heart rate

• atmosphere

To check how your thyroid is working, your health care provider (HCP) may order the following blood tests:

• TSH

• T4

• T3

• thyroid antibodies

What is TSH?

Thyroid-stimulating hormone (TSH) is a hormone that:

• It is made by the pituitary gland in the brain.

• It tells the thyroid gland how much thyroid hormone to make.

What do TSH test results mean?

• Low TSH levels occur when the thyroid gland is overactive.

• To slow down the thyroid gland, the pituitary gland stops producing TSH.

• This is called hyperthyroidism.

• Graves’ disease is the most common cause of hyperthyroidism.

• High TSH levels occur when the thyroid gland is underactive.

• To stimulate the thyroid gland to produce more T4, the pituitary gland produces additional TSH.

• This is called hypothyroidism

• Hashimoto’s disease is the most common cause of hypothyroidism.

A TSH test cannot diagnose the root cause of your thyroid problem.

What is T4?

T4 is thyroxine, one of the main hormones produced by the thyroid gland.

The T4 test is usually performed in conjunction with the TSH test.

T4 is measured by:

Free T4 Test

Total T4 test, which measures free T4 and bound T4

What do T4 test results mean?

Low levels of T4 may be a sign of:

• hypothyroidism

• Hashimoto’s disease

• Other thyroid disorders

High levels of T4 may be a sign of:

What is T3?

T3 is triiodothyronine, one of the main hormones produced by the thyroid gland.

The T3 test is used to:

• Diagnosis of hyperthyroidism when symptoms appear

• Diagnosing Pituitary Gland Problems

• Thyroid disease treatment monitoring

This test is not usually used to diagnose hypothyroidism.

What do T3 test results mean?

What are thyroid antibodies?

• If TSH, T3, or T4 are abnormal, a thyroid antibody test is performed to determine whether the antibodies may be attacking the thyroid gland.

What do antibody thyroid test results mean?

• Negative = If no thyroid antibodies are found, you most likely do not have autoimmune thyroid disease.

• Positive = You may have an autoimmune thyroid disease.

thyroid test values

These ranges vary by laboratory, but typical adult thyroid testing ranges include:

Consult your healthcare provider

The results of this test show how well your thyroid is working. Ask your HCP to help you understand what your results mean.

This training material was created with support from Immunovant, a member of the HealthyWomen Corporate Advisory Board.