Thyroid Dysfunction in PregnancyIodine Deficiency and Supplementation in PregnancyCHITTIMOJU, SANJITA B. MD; PEARCE, ELIZABETH N. MSc, MD Author Information Section of Endocrinology, Diabetes, Nutrition, and Weight Management, Boston University School of Medicine, Boston, Massachusetts The authors declare that they have nothing to disclose. Correspondence: Elizabeth N. Pearce, MSc, MD, Section of Endocrinology, Diabetes, Nutrition, and Weight Management, Boston University School of Medicine, 720 Harrison Ave., Suite 8100, Boston, MA. E-mail: [email protected] Clinical Obstetrics and Gynecology 62(2):p 330-338, June 2019. | DOI: 10.1097/GRF.0000000000000428 Buy Metrics Abstract Iodine deficiency during pregnancy is an important global public health issue and the leading preventable cause of neurodevelopmental impairments worldwide. The effects of severe iodine deficiency during pregnancy, including adverse obstetric outcomes and decreased child intelligence quotient, have been clearly established. However, the effects of mild-to-moderate deficiency remain less well understood. Pregnant and lactating women have higher iodine requirements than other adults; intakes of 220 to 250 µg/d in pregnancy and 250 to 290 µg/d in lactation. In this article, we describe iodine metabolism, iodine requirements in pregnancy and lactation, the effects of both iodine deficiency and excessive iodine intakes in pregnancy, and the efficacy of iodine supplementation. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.