Congenital Hypothyroidism

Hypothyroidism means the body doesn’t make enough thyroid hormone for normal growth, bone development, and to control how the body uses energy to function (metabolism). When the metabolism slows down, many body functions slow down.

Newborns are tested for hypothyroidism at birth. Congenital hypothyroidism is when a baby is born without enough thyroid hormone. Treatment for low thyroid levels must be started in the first weeks of life to prevent permanent harm to the brain and learning problems.

Signs and Symptoms

Most babies don’t have symptoms of low thyroid levels at birth. Symptoms that may develop soon after birth are:

Treatment

The treatment of hypothyroidism is simple, safe, and effective. You will give your baby a pill each day to replace the missing thyroid hormone. The medicine is called levothyroxine (Synthroid^®).

Since babies cannot swallow a pill, you will need to:

1. Crush the pill.
2. Mix it with 0.2 mL of sterile water, human milk, or formula.
3. Give it to your baby with a needleless syringe or a spoon (Picture 1). Your child’s doctor or health care provider will tell you which to use.

Don’t put the medicine in your baby’s bottle. If they don’t finish the bottle, they will not get enough medicine.

Follow-up

Your baby will see their doctor or health care provider every 2 to 3 months. Their blood will be tested at each visit to make sure they’re getting the right dose of medicine. It may need to be tested more often. Your baby will likely need thyroid medicine and regular blood tests for the rest of their life.

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