Objective: To assess the impact on cord blood (CB) thyroglobulin (Tg) of early iodine supplementation during pregnancy. Methods: A total of 111 healthy pregnant women with normal thyroid function were included in a prospective randomized study and divided into two groups with (150 µg/day) or without iodine supplementation started during the first trimester. Maternal smoking was assessed qualitatively by self-reported statements and quantitatively by cotininuria. Exhaustive thyroid tests were performed at delivery in the mother and in CB. Results: Third-trimester ioduria documented compliance with iodine supplementation (160 vs. 76 µg/l in controls). CB Tg was not different between the iodine and control groups (median 77 vs. 79.5 ng/ml, respectively) and did not correlate with maternal ioduria. CB Tg was higher in newborns from smoking mothers (114 vs. 64.7 ng/ml) and correlated with self-reported smoking status more than with maternal cotininuria. Nonsmokers had no difference in CB Tg whether they took iodine supplementation or not, as opposed to smokers, who tended to benefit from supplementation. Conclusions: Iodine supplementation does not significantly impact CB Tg in healthy nonsmoker pregnant women selected for normal thyroid function, as opposed to maternal smoking. CB Tg appears to be a marker of in utero tobacco exposure. In areas of mild iodine deficiency, iodine supplementation could especially benefit the fetuses of smokers.

Keywords:
Iodine, Smoking, Thyroglobulin, Cord blood, Pregnancy, Thyroid tests
1.
Zimmermann MB: Iodine deficiency. Endocr Rev 2009;30:376–408.
2.
WHO Secretariat, Andersson M, de Benoist B, Delange F, Zupan J: Prevention and control of iodine deficiency in pregnant and lactating women, and in children less than 2 years of age: conclusions and recommendations of the Technical Consultation. Public Health Nutr 2007;10:1606–1611.
3.
Vejbjerg P, Knudsen N, Perrild H, Laurberg P, Carlé A, Bülow Pedersen I, Rasmussen L, Ovesen L, Jorgensen T: Thyroglobulin as a marker of iodine nutrition status in the general population. Eur J Endocrinol 2009;161:475–481.
4.
Sava L, Tomaselli L, Runello F, Belfiore A, Vigneri R: Serum thyroglobulin levels are elevated in newborns from iodine-deficient areas. J Clin Endocrinol Metab 1986;62:429–432.
5.
Pacini F, Lari R, La Ricca P, Grasso L, Taddei D, Bardini N, Fenzi GF, Di Bartolo F, Baschieri L, Pinchera A: Serum thyroglobulin in newborns’ cord blood, in childhood and adolescence: a physiological indicator of thyroidal status. J Endocrinol Invest 1984;7:467–471.
6.
Pedersen KM, Laurberg P, Iversen E, Knudsen PR, Gregersen HE, Rasmussen OS, Larsen KR, Eriksen GM, Johannesen PL: Amelioration of some pregnancy-associated variations in thyroid function by iodine supplementation. J Clin Endocrinol Metab 1993;77:1078–1083.
7.
Glinoer, D, De Nayer P, Delange F, Lemone M, Toppet V, Spehl M, Grün JP, Kinthaert J, Lejeune B: A randomized trial for the treatment of mild iodine deficiency during pregnancy: maternal and neonatal effects. J Clin Endocrinol Metab 1995;80:258–269.
8.
Institut de Veille Sanitaire: L’état de santé de la population en France. Suivi des objectifs annexés à la Loi de Santé Publique. Rapport 2009–2010.
9.
Nohr 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.
10.
Antonangeli L, Maccherini D, Cavaliere R, Di Giulio C, Reinhardt B, Pinchera A, Aghini-Lombardi F: 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.
11.
Bartalena L, Bogazzi F, Tanda ML, Manetti L, Dell’Unto E, Martino E: Cigarette smoking and the thyroid. Eur J Endocrinol 1995;133:507–512.
12.
Utiger RD: Effects of smoking on thyroid function. Eur J Endocrinol 1998;138:368–369.
13.
Chanoine JP, Toppet V, Bourdoux P, Spehl M, Delange F: Smoking during pregnancy: a significant cause of neonatal thyroid enlargement. Br J Obstet Gynaecol 1991;98:65–68.
14.
Ericsson UB, Ivarsson SA, Persson PH: Thyroglobulin in cord blood. The influence of the mode of delivery and the smoking habits of the mother. Eur J Pediatr 1987;146:44–47.
15.
Gasparoni A, Autelli M, Ravagni-Probizer MF, Bartoli A, Regazzi-Bonora M, Chirico G, Rondini G: Effect of passive smoking on thyroid function in infants. Eur J Endocrinol 1998;138:379–382.
16.
McDonald S, Walker M, Ohlsson A, Murphy K, Beyene J, Perkins S: The effect of tobacco exposure on maternal and fetal thyroid function. Eur J Obstet Gynecol Reprod Biol 2008;140:38–42.
17.
Meberg A, Marstein S: Smoking during pregnancy. Effects on the fetal thyroid function. Acta Paediatr Scand 1986;75:762–766.
18.
Shields B, Hill A, Bilous M, Knight B, Hattersley A, Bilous R, Vaidya B: Cigarette smoking during pregnancy is associated with alterations in maternal and fetal thyroid function. J Clin Endocrinol Metab 2009;94:570–574.
19.
Soldin OP, Goughenour BE, Gilbert SZ, Landy HJ, Soldin SJ: Thyroid hormone levels associated with active and passive cigarette smoking. Thyroid 2009;19:817–823.
20.
Abalovich M, Amino N, Barbour LA, Cobin RH, De Groot LJ, Glinoer D, Mandel SJ, Stagnaro-Green A: Management of thyroid dysfunction during pregnancy and post partum: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab 2007;92(8 suppl):S1–S47.
21.
Oddoze C, Pauli AM, Pastor JJ: Rapid and sensitive high-performance liquid chromatographic determination of nicotine and cotinine in nonsmoker human and rat urines. J Chromatogr B Biomed Sci Appl 1998;708:95–101.
22.
Hieronimus S, Bec-Roche M, Ferrari P, Chevalier N, Fenichel P, Brucker-Davis F: Iodine status and thyroid function of 330 pregnant women from Nice area assessed during the second part of pregnancy. Ann Endocrinol (Paris) 2009;70:218–224.
23.
Klett M, Ohlig M, Manz F, Tröger J, Heinrich U: Effect of iodine supply on neonatal thyroid volume and TSH. Acta Paediatr 1999;88:18–20.
24.
Vejbjerg P, Knudsen N, Perrild H, Carlé A, Laurberg P, Bülow Pedersen I, Rasmussen L, Ovesen L, Jorgensen T: The impact of smoking on thyroid volume and function in relation to a shift towards iodine sufficiency. Eur J Epidemiol 2008;23:423–429.
25.
Ittermann T, Schmidt CO, Kramer A, Below H, John U, Thamm M, Wallaschofski H, Völzke H: Smoking as a risk factor for thyroid volume progression and incident goiter in a region with improved iodine supply. Eur J Endocrinol 2008;159:761–766.
26.
Cho NH, Choi HS, Kim KW, Kim HL, Lee SY, Choi SH, Lim S, Park YJ, Park Do J, Jang HC, Cho BY: Interaction between cigarette smoking and iodine intake and their impact on thyroid function. Clin Endocrinol 2010;73:264–270.
27.
Vanderver GB, Engel A, Lamm S: Cigarette smoking and iodine as hypothyroxinemic stressors in US women of childbearing age: a NHANES III analysis. Thyroid 2007;17:741–746.
28.
Liesenkötter KP, Göpel X, Bogner U, Stach B, Grüters A: Earliest prevention of endemic goiter by iodine supplementation during pregnancy. Eur J Endocrinol 1996;134:443–448.
29.
Pearce EN, Oken E, Gillman MW, Lee SL, Magnani B, Platek D, Braverman LE: Association of first-trimester thyroid function test values with thyroperoxidase antibody status, smoking and multivitamin use. Endocr Pract 2008;14:33–39.
30.
Velasco I, Carreira M, Santiago P, Muela JA, Garcia-Fuentes E, Sanchez-Munoz B, Garriga MJ, Gonzalez-Fernandez MC, Rodriguez A, Caballero FF, Machado A, Gonzalez-Romero S, Anarte MT, Soriguer F: Effect of iodine prophylaxis during pregnancy on neurocognitive development of children during the first two years of life. J Clin Endocrinol Metab 2009;94:3234–3241.
31.
Marco A, Vicente A, Castro E, Perez CE, Rodriguez O, Merchan MA, Sastre J, Canocas B, Maqueda E, Pena V, Lopez J: Patterns of iodine intake and urine iodine concentrations during pregnancy and blood thyroid-stimulating hormone concentrations in newborn progeny. Thyroid 2010;20:1295–1299.
32.
Zimmermann MB, Aeberli I, Torresani T, Bürgi H: Increasing the iodine concentration in the Swiss iodized salt program markedly improved iodine status in pregnant women and children: a 5-y prospective national study. Am J Clin Nutr 2005;82:388–392.
33.
Zimmermann MB: The adverse effects of mild to moderate iodine deficiency during pregnancy and childhood: a review. Thyroid 2007;17:829–835.
34.
Fukayama H, Nasu M, Murakami S, Sugawara M: Examination of antithyroid effects of smoking products in cultured thyroid follicles: only thiocyanate is a potent antithyroid agent. Acta Endocrinol (Copenh) 1992;127:520–525.
35.
Gondou A, Toyoda N, NishikawaM, Yonemoto T, Sakaguchi N, Tokoro T, Inada M: Effect of nicotine on type 3 deiodinase activity in cultured rat glial cells. Endocr J 1999;46:107–112.
36.
Zoeller RT: Environmental chemicals impacting the thyroid: targets and consequences. Thyroid 2007;17:811–817.
37.
Brucker-Davis F, Ferrari P, Boda-Buccino M, Wagner-Mahler K, Pacini P, Gal J, Azuar P, Fenichel P: Cord blood thyroid tests in boys born with and without cryptorchidism. Correlations with birth parameters and in utero xenobiotics exposure. Thyroid 2011;21:1133–1141.
38.
Pearce EN: What do we know about iodine supplementation in pregnancy? J Clin Endocrinol Metab 2009;94:3188–3190.
© 2012 European Thyroid Association Published by S. Karger AG, Basel
2012
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