{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T22:50:51Z","timestamp":1788994251070,"version":"build-2803163510"},"reference-count":31,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2019,2,20]],"date-time":"2019-02-20T00:00:00Z","timestamp":1550620800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000272","name":"National Institute for Health Research","doi-asserted-by":"publisher","award":["PR-R10-0514-11004"],"award-info":[{"award-number":["PR-R10-0514-11004"]}],"id":[{"id":"10.13039\/501100000272","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Severe iodine deficiency in mothers is known to impair foetal development. Pregnant women in the UK may be iodine insufficient, but recent assessments of iodine status are limited. This study assessed maternal urinary iodine concentrations (UIC) and birth outcomes in three UK cities. Spot urines were collected from 541 women in London, Manchester and Leeds from 2004\u20132008 as part of the Screening for Pregnancy End points (SCOPE) study. UIC at 15 and 20 weeks\u2019 gestation was estimated using inductively coupled plasma-mass spectrometry (ICP-MS). Associations were estimated between iodine status (UIC and iodine-to-creatinine ratio) and birth weight, birth weight centile (primary outcome), small for gestational age (SGA) and spontaneous preterm birth. Median UIC was highest in Manchester (139 \u03bcg\/L, 95% confidence intervals (CI): 126, 158) and London (130 \u03bcg\/L, 95% CI: 114, 177) and lowest in Leeds (116 \u03bcg\/L, 95% CI: 99, 135), but the proportion with UIC &lt;50 \u00b5g\/L was &lt;20% in all three cities. No evidence of an association was observed between UIC and birth weight centile (\u22120.2% per 50 \u03bcg\/L increase in UIC, 95% CI: \u22121.3, 0.8), nor with odds of spontaneous preterm birth (odds ratio = 1.00, 95% CI: 0.84, 1.20). Given the finding of iodine concentrations being insufficient according to World Health Organization (WHO) guidelines amongst pregnant women across all three cities, further studies may be needed to explore implications for maternal thyroid function and longer-term child health outcomes.<\/jats:p>","DOI":"10.3390\/nu11020441","type":"journal-article","created":{"date-parts":[[2019,2,20]],"date-time":"2019-02-20T11:45:39Z","timestamp":1550663139000},"page":"441","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Maternal Iodine Status and Associations with Birth Outcomes in Three Major Cities in the United Kingdom"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3164-3271","authenticated-orcid":false,"given":"Charles J. P.","family":"Snart","sequence":"first","affiliation":[{"name":"Department of Clinical and Population Science, Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1633-8842","authenticated-orcid":false,"given":"Claire","family":"Keeble","sequence":"additional","affiliation":[{"name":"Leeds Institute for Data Analytics, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4559-5573","authenticated-orcid":false,"given":"Elizabeth","family":"Taylor","sequence":"additional","affiliation":[{"name":"Department of Clinical and Population Science, Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3421-0121","authenticated-orcid":false,"given":"Janet E.","family":"Cade","sequence":"additional","affiliation":[{"name":"Nutritional Epidemiology Group, School of Food Science &amp; Nutrition, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul M.","family":"Stewart","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Zimmermann","sequence":"additional","affiliation":[{"name":"Laboratory for Human Nutrition, Institute of Food, Nutrition and Health, Swiss Federal Institute of Technology (ETH), 8092 Z\u00fcrich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen","family":"Reid","sequence":"additional","affiliation":[{"name":"Earth Surface Science Institute, School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diane E.","family":"Threapleton","sequence":"additional","affiliation":[{"name":"Department of Clinical and Population Science, Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lucilla","family":"Poston","sequence":"additional","affiliation":[{"name":"Division of Women\u2019s Health, Women\u2019s Health Academic Centre, King\u2019s College London, London SE1 7EH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jenny E.","family":"Myers","sequence":"additional","affiliation":[{"name":"Maternal and Fetal Health Research Centre, Institute of Human Development, University of Manchester, Manchester M13 0JH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nigel A. B.","family":"Simpson","sequence":"additional","affiliation":[{"name":"Division of Women\u2019s and Children\u2019s Health, School of Medicine, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7035-3096","authenticated-orcid":false,"given":"Darren C.","family":"Greenwood","sequence":"additional","affiliation":[{"name":"Department of Clinical and Population Science, Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds LS2 9JT, UK"},{"name":"Leeds Institute for Data Analytics, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura J.","family":"Hardie","sequence":"additional","affiliation":[{"name":"Department of Clinical and Population Science, Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,20]]},"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":"1571","DOI":"10.1017\/S1368980007360941","article-title":"Iodine requirements during pregnancy, lactation and the neonatal period and indicators of optimal iodine nutrition","volume":"10","author":"Delange","year":"2007","journal-title":"Public Health Nutr."},{"key":"ref_3","unstructured":"WHO, UNICEF, and ICCIDD (2007). 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