Thyroid Hormone Tests: About Your Child's Test
What are they?
Thyroid hormone tests are blood tests that check to see how well your child's thyroid gland is working. The
thyroid gland is a butterfly-shaped gland that lies in front of your child's windpipe (trachea). It's just
below the voice box (larynx). The thyroid gland makes hormones that control the way your child's body uses
energy (metabolism).
These tests show your child's thyroid hormone levels. Your child's thyroid may be making too much or too
little hormone.
Why are these tests done?
Thyroid hormone tests are done to find the cause of an abnormal thyroid-stimulating hormone (TSH) test. TSH
tests can also check how well treatment for thyroid disease is working. They are used in newborns to find out
if the thyroid gland is working as it should.
How do you prepare for the test?
If your child takes thyroid medicines, tell the doctor when your child took the last dose. Your child may
need to stop taking thyroid medicines for a short time before having these tests.
How is the test done?
Blood test
A health professional uses a needle to take a blood sample, usually from the arm.
Heel stick
A heel stick is used to get a blood sample from a baby. The baby's heel is poked, and several drops of blood
are collected. Your baby may have a tiny bruise where the heel was poked.
What happens after the test?
Follow-up care is a key part of your child's treatment and safety. Be sure to make and go to all
appointments, and call your doctor if your child is having problems. Ask your doctor when you can expect to
have your child's test results.
Current as of: May 13, 2023
Content Version: 14.0
Care instructions adapted under license by your
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