Congenital Hypothyroidism Caused by Excess Prenatal Maternal Iodine Ingestion

We report the cases of 3 infants with congenital hypothyroidism detected with the use of our newborn screening program, with evidence supporting excess maternal iodine ingestion (12.5 mg/d) as the etiology. Levels of whole blood iodine extracted from their newborn screening specimens were 10 times above mean control levels. Excess iodine ingestion from nutritional supplements is often unrecognized. (J Pediatr 2012;161:760-2)