Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Effects of maternal iodine supplementation during pregnancy and lactation on iodine status and neonatal thyroid-stimulating hormone



To determine the iodine status in pregnant and lactating women, as well as neonatal thyroid-stimulating hormone (TSH) concentration.

Study Design:

Pregnant women cared at our hospital, the University Hospital in Bangkok, had routinely received 200 μg iodine tablet daily since October 2010. Urinary iodine concentrations (UICs) of 1508 pregnant and 87 lactating women and 76 offspring and breast milk iodine concentration (BMIC) (n=57) were measured. Cord serum TSH levels from hypothyroidism screening were analyzed.


Median UIC levels of pregnant and lactating women were 170.6 and 138.0 μg l–1, respectively. Median BMIC and infants’ UIC at 2-month postpartum in iodine-supplemented group were higher than the respective values of non-supplemented group. Median cord serum TSH level obtained before iodine supplementation (n=8332) was higher than that obtained after supplementation (n=5181; 7.3 vs 5.2 mU l–1).


Maternal iodine supplementation improved iodine nutrition in their breast-fed offspring. A trend toward declining in cord serum TSH values after iodine supplementation indicates improvement of iodine status during pregnancy.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Get just this article for as long as you need it


Prices may be subject to local taxes which are calculated during checkout

Figure 1
Figure 2
Figure 3
Figure 4


  1. Zimmermann MB . Iodine deficiency. Endocr Rev 2009; 30: 376–408.

    Article  CAS  Google Scholar 

  2. Rajatanavin R . Iodine deficiency in pregnant women and neonates in Thailand. Public Health Nutr 2007; 10: 1602–1605.

    Article  Google Scholar 

  3. Jaruratanasirikul S, Sangsupawanich P, Koranantakul O, Chavitan P, Ruanengrairatanaroj P, Sriplung H et al. Maternal iodine status and neonatal thyroid-stimulating hormone concentration: a community survey in Songkhla, southern Thailand. Public Health Nutr 2009; 12: 2279–2284.

    Article  Google Scholar 

  4. Antonangeli L, Maccherini D, Cavaliere R, Di Giulio C, Reinhardt B, Pinchera A et al. Comparison of two different doses of iodide in the prevention of gestational goiter in marginal iodine deficiency: a longitudinal study. Eur J Endocrinol 2002; 147: 29–34.

    Article  CAS  Google Scholar 

  5. Lamm SH, Chen R, Engel A, Hollowell JG . Effect of iodine supplementation on urine iodine in iodine-sufficient population-pregnant US women [Abstract]. Thyroid 2005; 15: S-171.

    Google Scholar 

  6. WHO, UNICEF, ICCIDD. Indicators for Assessing Iodine Deficiency Disorders and Their Control through Salt Iodization . World Health Organization, WHO/NUT/94.6: Geneva, Switzerland, 1994; 1–55.

  7. Oltarzewski M, Szymborski J . Neonatal hypothyroid screening in monitoring of iodine deficiency and iodine supplementation in Poland. J Endocrinol Invest 2003; 26: 27–31.

    CAS  PubMed  Google Scholar 

  8. Chan SS, Hams G, Wiley VT, Wilcken B, McElduff A . Postpartum maternal iodine status and the relationship to neonatal thyroid function. Thyroid 2003; 13: 873–876.

    Article  CAS  Google Scholar 

  9. Spitzweg C, Joba W, Eisenmenger W, Heufelder AE . Analysis of human sodium iodide symporter gene expression in extrathyroidal tissues and cloning of its complementary deoxyribonucleic acids from salivary gland, mammary gland, and gastric mucosa. J Clin Endocrinol Metab 1998; 83: 1746–1751.

    Article  CAS  Google Scholar 

  10. Delange F . Iodine requirements during pregnancy, lactation and the neonatal period and indicators of optimal iodine nutrition. Public Health Nutr 2007; 10: 1571–1580.

    Article  Google Scholar 

  11. Pedersen KM, Laurberg P, Iversen E, Knudsen PR, Gregersen SE, Rasmussen OS et al. Amelioration of some pregnancy-associated variations in thyroid function by iodine supplementation. J Clin Endocrinol Metab 1993; 77: 1078–1083.

    CAS  PubMed  Google Scholar 

  12. Glinoer D, De Nayer P, Delange F, Lemone M, Toppet V, Spehl M et al. A randomized trial for the treatment of mild iodine deficiency during pregnancy: maternal and neonatal effects. J Clin Endocrinol Metab 1995; 80: 258–269.

    CAS  PubMed  Google Scholar 

  13. WHO, UNICEF, ICCIDD. Assessment of the Iodine Deficiency Disorders and Monitoring Their Elimination. WHO/NHD/01.1 World Health Organization: Geneva Switzerland, 2007.

  14. Division of Nutrition, Ministry of Public Health. Surveillance System for ‘Tracking Progress Towards the Sustainable Elimination of Iodine Deficiency Disorders in Thailand: Result of 2000–2004’. Division of Nutrition, Ministry of Public Health: Bangkok, 2005.

  15. Nøhr SB, Laurberg P . Opposite variations in maternal and neonatal thyroid function induced by iodine supplementation during pregnancy. J Clin Endocrinol Metab 2000; 85: 623–627.

    Article  Google Scholar 

  16. Mezosi E, Molnar I, Jakab A, Balogh E, Karanyi Z, Nagy P et al. Prevalence of iodine deficiency and goitre during pregnancy in East Hungary. Eur J Endocrinol 2000; 143: 479–483.

    Article  CAS  Google Scholar 

  17. Smyth PP . Variation in iodine handling during normal pregnancy. Thyroid 1999; 9: 637–642.

    Article  CAS  Google Scholar 

  18. Public Health Committee of the American Thyroid Association: Public Health Committee of the American Thyroid Association Becker DV, Public Health Committee of the American Thyroid Association Braverman LE, Public Health Committee of the American Thyroid Association Delange F, Public Health Committee of the American Thyroid Association Dunn JT, Public Health Committee of the American Thyroid Association Franklyn JA et al. Iodine supplementation for pregnancy and lactation-United States and Canada: recommendations of the American Thyroid Association. Thyroid 2006; 16: 949–951.

    Article  Google Scholar 

  19. International Council for the Control of Iodine Deficiency Disorders (ICCIDD). Tracking progress towards sustainable elimination of iodine deficiency disorders in Thailand. External Review of the IDD Elimination Program in Thailand. ICCIDD: Ottawa, Canada, 2009.

  20. Smyth PP, Hetherton AM, Smith DF, Radcliff M, O’Herlihy C . Maternal iodine status and thyroid volume during pregnancy: correlation with neonatal iodine intake. J Clin Endocrinol Metab 1997; 82: 2840–2843.

    Article  CAS  Google Scholar 

  21. Brander L, Als C, Buess H, Haldimann F, Harder M, Hanggi W et al. Urinary iodine concentration during pregnancy in an area of unstable dietary iodine intake in Switzerland. J Endocrinol Invest 2003; 26: 389–396.

    Article  CAS  Google Scholar 

  22. Fuse Y, Ohashi T, Yamaguchi S, Yamaguchi M, Shishiba Y, Irie M . Iodine status of pregnant and postpartum Japanese women: effect of iodine intake on maternal and neonatal thyroid function in an iodine-sufficient area. J Clin Endocrinol Metab 2001; 96: 3846–3854.

    Article  Google Scholar 

  23. Mulrine HM, Skeaff SA, Ferguson EL, Gray AR, Valeix P . Breast-milk iodine concentration declines over the first 6 mo postpartum in iodine-deficient women. Am J Clin Nutr 2001; 92: 849–856.

    Article  Google Scholar 

  24. Institute of Medicine, Academy of Sciences, USA. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium and Zinc. National Academy Press: Washington, DC, 2001.

  25. Tylek-Lemańska D, Rybakowa M, Kumorowicz-Kopiec M, Dziatkowiak H, Ratajczak R . Iodine deficiency disorders incidence in neonates based on the experience with mass screening for congenital hypothyroidism in southeast Poland in the years 1985–2000. J Endocrinol Invest 2003; 26: 32–38.

    PubMed  Google Scholar 

  26. Burns R, Mayne PD, O’Herlihy C, Smith DF, Higgins M, Staines A et al. Can neonatal TSH screening reflect trends in population iodine intake? Thyroid 2008; 18: 883–888.

    Article  CAS  Google Scholar 

  27. Li M, Eastman CJ . Neonatal TSH screening: is it a sensitive and reliable tool for monitoring iodine status in populations? Best Pract Res Clin Endocrinol Metab 2010; 24: 63–75.

    Article  Google Scholar 

  28. Hynes KL, Otahal P, Hay I, Burgess JR . Mild iodine deficiency during pregnancy is associated with reduced educational outcomes in the offspring: 9-year follow-up of the gestational iodine cohort. J Clin Endocrinol Metab 2013; 98: 1954–1963.

    Article  CAS  Google Scholar 

  29. Bath SC, Steer CD, Golding J, Emmett P, Rayman MP . Effect of inadequate iodine status in UK pregnant women on cognitive outcomes in their children: results from the Avon Longitudinal Study of Parents and Children (ALSPAC). Lancet 2013; 382: 331–337.

    Article  CAS  Google Scholar 

Download references


This study was supported by a research grant (no. MURA2012/50) from the Faculty of Medicine Ramathibodi Hospital, Mahidol University, Thailand. We thank Professor Rajata Rajatanavin for the constructive critique of the manuscript.

Author information

Authors and Affiliations


Corresponding author

Correspondence to P Mahachoklertwattana.

Ethics declarations

Competing interests

The authors declare no conflict of interest.

Rights and permissions

Reprints and Permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Sukkhojaiwaratkul, D., Mahachoklertwattana, P., Poomthavorn, P. et al. Effects of maternal iodine supplementation during pregnancy and lactation on iodine status and neonatal thyroid-stimulating hormone. J Perinatol 34, 594–598 (2014).

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


Quick links