The thyroid is a gland in the lower neck. It makes hormones that regulate growth, brain development, and metabolism. Hypothyroidism is a low or absent production of these hormones. Congenital means the conditions is present since birth.
The Thyroid Gland
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If this condition is not treated it can cause damage to the brain. This can lead to intellectual disability and abnormal growth.
In most cases, the cause is unknown. The most common known cause is abnormal development of the thyroid gland. A small percentage of cases are inherited.
Babies born before 40 weeks may have a temporary shortage in the thyroid hormones.
Factors that may increase the risk of congenital hypothyroidism include:
Symptoms or signs take time to develop. The symptoms of congenital hypothyroidism may include the following:
At birth, most infants are screened for this condition. Blood tests will be able to identify thyroid levels. Images of the thyroid may also be taken with:
The outcome is best if the condition is caught early. It is important to start treatment before the brain and nervous system are fully developed. If treatment is given early, it could prevent damage. Left untreated, the condition can lead to poor mental development and delayed growth.
Medication will treat the hypothyroidism. The medication will replace the missing hormones.
Once medication starts, the levels of thyroid hormones are checked often. This will help to keep the values within normal range. If values are kept within a normal range, there are no side effects or complications.
Most cases cannot be prevented. The following are some things the mother can do during pregnancy to reduce the risk:
Genetics Home Reference
American Medical Association
American Thyroid Association
Thyroid Foundation of Canada
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Accessed December 31, 2012.
Update of newborn screening and therapy for congenital hypothyroidism. American Academy of Pediatrics. Pediatrics. 2006;117:2290-2303.
Last reviewed March 2013 by Kim Carmichael, MD
Last Updated: 3/15/2013