RT Book, Section A1 Fisher, Delbert A. A2 Rudolph, Colin D. A2 Rudolph, Abraham M. A2 Lister, George E. A2 First, Lewis R. A2 Gershon, Anne A. SR Print(0) ID 7053228 T1 Chapter 527. Hypothyroidism in the Infant T2 Rudolph's Pediatrics, 22e YR 2011 FD 2011 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-149723-7 LK accesspediatrics.mhmedical.com/content.aspx?aid=7053228 RD 2024/10/06 AB Causes of hypothyroidism are listed in Table 527-1. Transient neonatal hypothyroidism occurs in premature infants, and may be caused by drugs or maternal antibodies. The most common cause of nonendemic congenital hypothyroidism is defective thyroid embryogenesis. Inborn defects in thyroid hormone synthesis or action are the second most common cause of congenital hypothyroidism.1-13 Other causes include intrauterine exposure to goitrogenic agents and hypothalamic-pituitary disorders. These usually occur in the setting of panhypopituitarism, but isolated defects in thyrotropin-releasing hormone (TRH) or thyroid-stimulating hormone (TSH) do occur.5-7