Iodine-Induced Fetal Hypothyroidism: Diagnosis and Treatment with Intra-Amniotic Levothyroxine

Macy T Hardley; Andrew H Chon; Jorge Mestman; Caroline T Nguyen; Mitchell E Geffner; Ramen H Chmait

doi:10.1159/000488776

Iodine-Induced Fetal Hypothyroidism: Diagnosis and Treatment with Intra-Amniotic Levothyroxine

Horm Res Paediatr. 2018;90(6):419-423. doi: 10.1159/000488776. Epub 2018 May 23.

Authors

Macy T Hardley¹, Andrew H Chon², Jorge Mestman³, Caroline T Nguyen⁴, Mitchell E Geffner⁵, Ramen H Chmait⁶

Affiliations

¹ Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
² Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
³ Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine and Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
⁴ Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
⁵ The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
⁶ Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA, chmait@usc.edu.

PMID: 29791909
DOI: 10.1159/000488776

Abstract

Background: Iodine is necessary for fetal thyroid development. Excess maternal intake of iodine can cause fetal hypothyroidism due to the inability to escape from the Wolff-Chaikoff effect in utero.

Case report: We report a case of fetal hypothyroid goiter secondary to inadvertent excess maternal iodine ingestion from infertility supplements. The fetus was successfully treated with intra-amniotic levothyroxine injections. Serial fetal blood sampling confirmed fetal escape from the Wolff-Chaikoff effect in the mid third trimester. Early hearing test and neurodevelopmental milestones were normal.

Conclusion: Intra-amniotic treatment of fetal hypothyroidism may decrease the rate of impaired neurodevelopment and sensorineural hearing loss.

Keywords: Fetal goiter; Fetal hypothyroidism; Intra-amniotic treatment; Iodine; Wolff-Chaikoff effect.

Publication types

Case Reports

MeSH terms

Adult
Congenital Hypothyroidism* / blood
Congenital Hypothyroidism* / chemically induced
Congenital Hypothyroidism* / diagnosis
Congenital Hypothyroidism* / drug therapy
Female
Fetal Diseases* / blood
Fetal Diseases* / chemically induced
Fetal Diseases* / diagnosis
Fetal Diseases* / drug therapy
Goiter* / blood
Goiter* / chemically induced
Goiter* / diagnosis
Goiter* / drug therapy
Humans
Iodine / administration & dosage
Iodine / adverse effects*
Male
Pregnancy
Prenatal Diagnosis
Thyroxine / administration & dosage*

Substances

Iodine
Thyroxine