{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,25]],"date-time":"2026-07-25T04:22:02Z","timestamp":1784953322865,"version":"3.55.0"},"reference-count":35,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2019,10,25]],"date-time":"2019-10-25T00:00:00Z","timestamp":1571961600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000063","name":"Office of Dietary Supplements","doi-asserted-by":"publisher","award":["HHSN2752011000011 and HHSN27500009"],"award-info":[{"award-number":["HHSN2752011000011 and HHSN27500009"]}],"id":[{"id":"10.13039\/100000063","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Finnish Medical Association of Clinical Chemistry","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]},{"name":"Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Normal maternal thyroid function during pregnancy is essential for fetal development and depends upon an adequate supply of iodine. Little is known about how iodine status is associated with preterm birth and small for gestational age (SGA) in mildly iodine insufficient populations. Our objective was to evaluate associations of early pregnancy serum iodine, thyroglobulin (Tg), and thyroid-stimulating hormone (TSH) with odds of preterm birth and SGA in a prospective, population-based, nested case-control study from all births in Finland (2012\u20132013). Cases of preterm birth (n = 208) and SGA (n = 209) were randomly chosen from among all singleton births. Controls were randomly chosen from among singleton births that were not preterm (n = 242) or SGA (n = 241) infants during the same time period. Women provided blood samples at 10\u201314 weeks\u2019 gestation for serum iodide, Tg and TSH measurement. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for preterm birth and SGA. Each log-unit increase in serum iodide was associated with higher odds of preterm birth (adjusted OR = 1.19, 95% CI = 1.02\u20131.40), but was not associated with SGA (adjusted OR = 1.01, 95% CI = 0.86\u20131.18). Tg was not associated with preterm birth (OR per 1 log-unit increase = 0.87, 95% CI = 0.73\u20131.05), but was inversely associated with SGA (OR per log-unit increase = 0.78, 95% CI = 0.65\u20130.94). Neither high nor low TSH (versus normal) were associated with either outcome. These findings suggest that among Finnish women, iodine status is not related to SGA, but higher serum iodide may be positively associated with preterm birth.<\/jats:p>","DOI":"10.3390\/nu11112573","type":"journal-article","created":{"date-parts":[[2019,10,25]],"date-time":"2019-10-25T04:41:27Z","timestamp":1571978487000},"page":"2573","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["The Joint Role of Thyroid Function and Iodine Status on Risk of Preterm Birth and Small for Gestational Age: A Population-Based Nested Case-Control Study of Finnish Women"],"prefix":"10.3390","volume":"11","author":[{"given":"Alexandra C.","family":"Purdue-Smithe","sequence":"first","affiliation":[{"name":"Epidemiology Branch, Division of Intramural Population Health Research, <i>Eunice Kennedy Shriver<\/i> National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tuija","family":"M\u00e4nnist\u00f6","sequence":"additional","affiliation":[{"name":"Northern Finland Laboratory Centre NordLab, 90120 Oulu, Finlan"},{"name":"Department of Clinical Chemistry, University of Oulu, 90120 Oulu, Finland"},{"name":"Medical Research Center Oulu, Oulu University Hospital and University of Oulu, 90120 Oulu, Finland"},{"name":"Finnish Institute for Health and Welfare, 00290 Helsinki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Griffith A.","family":"Bell","sequence":"additional","affiliation":[{"name":"Ariadne Labs, Brigham and Women\u2019s Hospital, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA"},{"name":"Harvard T.H. Chan School of Public Health, Department of Health Policy and Management, Boston, MA 02115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0133-3176","authenticated-orcid":false,"given":"Sunni L.","family":"Mumford","sequence":"additional","affiliation":[{"name":"Epidemiology Branch, Division of Intramural Population Health Research, <i>Eunice Kennedy Shriver<\/i> National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aiyi","family":"Liu","sequence":"additional","affiliation":[{"name":"Biostatistics and Bioinformatics Branch, Division of Intramural Population Health Research, <i>Eunice Kennedy Shriver<\/i> National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kurunthachalam","family":"Kannan","sequence":"additional","affiliation":[{"name":"Wadsworth Center, New York State Department of Health, Albany, NY 12201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Un-Jung","family":"Kim","sequence":"additional","affiliation":[{"name":"Wadsworth Center, New York State Department of Health, Albany, NY 12201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eila","family":"Suvanto","sequence":"additional","affiliation":[{"name":"Northern Finland Laboratory Centre NordLab, 90120 Oulu, Finlan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helj\u00e4-Marja","family":"Surcel","sequence":"additional","affiliation":[{"name":"Biobank Borealis of Northern Finland, Oulu University Hospital, 90120 Oulu, Finland"},{"name":"Faculty of Medicine, University of Oulu, 90120 Oulu, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8254-7525","authenticated-orcid":false,"given":"Mika","family":"Gissler","sequence":"additional","affiliation":[{"name":"Finnish Institute for Health and Welfare, 00290 Helsinki, Finland"},{"name":"Karolinska Institute, 17177 Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4496-332X","authenticated-orcid":false,"given":"James L.","family":"Mills","sequence":"additional","affiliation":[{"name":"Epidemiology Branch, Division of Intramural Population Health Research, <i>Eunice Kennedy Shriver<\/i> National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1251","DOI":"10.1016\/S0140-6736(08)61005-3","article-title":"Iodine-deficiency disorders","volume":"372","author":"Zimmermann","year":"2008","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"580","DOI":"10.1089\/thy.2015.0418","article-title":"Subclinical Hypothyroidism in Pregnancy: A Systematic Review and Meta-Analysis","volume":"26","author":"Maraka","year":"2016","journal-title":"Thyroid"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"31969","DOI":"10.3402\/fnr.v60.31969","article-title":"Iodine status in the Nordic countries-past and present","volume":"60","author":"Nystrom","year":"2016","journal-title":"Food Nutr. 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