Congenital hypothyroidism

Congenital hypothyroidism is a condition that affects infants from birth and results from a partial or complete loss of thyroid function (hypothyroidism). The thyroid gland makes hormones that play an important role in regulating growth, brain development, and metabolism in the body. Congenital hypothyroidism occurs when the thyroid gland fails to develop or function properly. In the United States and many other countries, all newborns are tested for congenital hypothyroidism as part of newborn screening. If untreated, congenital hypothyroidism can lead to intellectual disability and abnormal growth. If treatment begins in the first month after birth, infants usually develop normally. Treatment involves medication to replace the missing thyroid hormones, such as levothyroxine. Most cases of congenital hypothyroidism occur in people with no history of the disorder in their family. About 15-20% of cases are due to an underlying gene mutation. Rarely, congenital hypothyroidism can be a symptom included in a larger genetic disorder called a syndrome.