Why Screen for Congenital Hypothyroidism?
In the United States, congenital hypothyroidism occurs in 1 of 3,000 to 4,000 infants. It is one of the most common preventable causes of mental retardation, according to the American Academy of Pediatrics. A screening test (obtaining blood from the infant's heel) should be done on all newborns between 2 and 4 days of age. Without prompt treatment, most affected children gradually develop growth failure, irreversible mental retardation, and a variety of neuropsychologic deficits, comprising the syndrome of cretinism. These complications have become rare since the introduction in the 1970s of routine neonatal screening and early treatment of congenital hypothyroidism.
U.S. Preventive Services Task Force, 2008