Maternal iodine excess: an uncommon cause of acquired neonatal hypothyroidism.

All of us who work in pediatrics know that adequate thyroid function in a newborn is absolutely critical for the infants development.  Nothing is worse than hypothyroidism in a newborn infant.  While the infant needs low to modest levels of potassium iodine to make all the thyroxin it needs,  TOO MUCH iodine basically shuts the infant thyroid down.  Remember,  there is a pump in the human breast that collects all iodine molecules that pass the mothers breast and transfers that iodine molecule into the milk.  This was nature's way to make sure the baby could make adequate thyroxin to grow. 

However,  too much Iodine (such as from seaweed, or repeated Betadyne vaginal douches over time), may completely shut down the infants thyroid and lead to hypothyroidism.   This study again shows that too much iodine from seaweed ingestion by the mom,  may ultimately shut down the infants thryoid as well.  Please heed these repeated warnings that EXCESS CONSUMPTION OF IODINE FROM ANY SOURCE MAY SUPPRESS YOUR INFANTS THRYOID FUNCTION.  This will ultimately and severely harm your infant.  Seaweed and kelp may contain up to 20 times the recommended daily intake. Recommended dietary allowance for iodine by the US Institute for Medicine in breastfeeding women is 290 µg/day. Excessive iodine exposure (from any source) may cause hypothyroidism in infants.   TWH


J Pediatr Endocrinol Metab. 2018 Jul 27. pii: /j/jpem.ahead-of-print/jpem-2018-0138/jpem-2018-0138.xml. doi: 10.1515/jpem-2018-0138. [Epub ahead of print]

Maternal iodine excess: an uncommon cause of acquired neonatal hypothyroidism.

Hamby T1,2, Kunnel N3, Dallas JS4, Wilson DP4.

Author information

Abstract

Background Excessive iodine exposure is an often overlooked cause of neonatal hypothyroidism. Case presentation We present an infant with iodine-induced hypothyroidism, which was detected at age 15 days by newborn screening. The infant's iodine excess resulted from maternal intake of seaweed soup both during and after pregnancy. Treatment included discontinuation of seaweed soup, temporary interruption of breastfeeding and short-term levothyroxine therapy. By age 4 months, the infant's hypothyroidism had resolved, and her growth and development were normal. Conclusions This case illustrates the importance of considering excess dietary iodine as a possible cause of hypothyroidism in infants.

KEYWORDS:

hypothyroidism; iodine; thyroid

PMID: 30052521