Screening of newborn infants for hypothyroidism. Two years' experience in South Autralia.

Over a period of two years, 40,000 newborn infants in South Australia have been screened for congenital hypothyroidism by the measurement of thyroxine and, on selected samples, of thyroid stimulating hormone. Samples were those obtained for an established newborn screening programme in the State. Eight infants with hypothyroidism were detected; in seven, this was due to congenital agenesis of the thyroid gland and one infant had residual thyroid tissue. A further three sick infants had abnormalities of thyroid function; in two, this was transient and reverted to normal after several weeks and the third infant died. Three infants had thyroxine-binding globulin deficiency.