{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T14:43:43Z","timestamp":1785163423412,"version":"3.55.0"},"reference-count":22,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,1,31]],"date-time":"2025-01-31T00:00:00Z","timestamp":1738281600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background: Iodine is fundamental for the synthesis of thyroid hormones, which play a central role in foetal neurological development. The need for an iodine-containing supplement (ICS) in L-T4-treated women during pregnancy is still a subject of debate. Aim of the Study: The aim of the study is to investigate the iodine status in women with autoimmune thyroiditis (AT) who have or have not been treated with L-T4. Methods: This was a cross-sectional, observational study involving pregnant women with AT, treated with\/without L-T4. Upon enrolment, women provided a urine sample (to measure the urinary iodine concentration (UIC), which was normalised to urinary creatinine values (UI\/Creat)), and completed a questionnaire. TSH, FT4, and neonatal TSH were also obtained. Results: Among women taking an ICS, 74.1% had a UI\/Creat level \u2265 150 \u03bcg\/g, compared with only 46.2% of those not taking an ICS (p = 0.03). Among L-T4 users only, a UI\/Creat level \u2265 150 \u03bcg\/g was more frequent in ICS users than in non-ICS users (72.8% vs. 41.7%) (p = 0.03). In the multivariate analysis, ICS use was the only independent variable for UI\/Creat \u2265 150 \u03bcg\/g (OR: 3.4; CI: 1.1\u201310.9) (p = 0.04). There was a tendency towards higher UI\/Creat levels as the L-T4 (\u00b5g\/Kg) dosage increased, although no correlation was found. Newborns of women taking an ICS were found to have elevated neonatal TSH (2.8 mIU\/L vs. 1.7 mIU\/L) (p = 0.04). All newborns with a TSH &gt;5 mUI\/L were those of women taking supplements. Conclusions: Women with AT taking L-T4 still need iodine supplementation, although the amount should be regulated on the basis of their L-T4 dosage.<\/jats:p>","DOI":"10.3390\/nu17030542","type":"journal-article","created":{"date-parts":[[2025,1,31]],"date-time":"2025-01-31T09:16:26Z","timestamp":1738314986000},"page":"542","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Women with Autoimmune Thyroiditis Taking Levothyroxine During Pregnancy: Is Iodine Supplementation Needed?"],"prefix":"10.3390","volume":"17","author":[{"given":"Simona","family":"Censi","sequence":"first","affiliation":[{"name":"Endocrinology Unit, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giulia","family":"Messina","sequence":"additional","affiliation":[{"name":"Endocrinology Unit, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emma","family":"Feligiotti","sequence":"additional","affiliation":[{"name":"Endocrinology Unit, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina","family":"Clausi","sequence":"additional","affiliation":[{"name":"Endocrinology Unit, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilaria","family":"Piva","sequence":"additional","affiliation":[{"name":"Endocrinology Unit, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8745-6171","authenticated-orcid":false,"given":"Daniela","family":"Basso","sequence":"additional","affiliation":[{"name":"Laboratory Medicine, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Isabella","family":"Merante Boschin","sequence":"additional","affiliation":[{"name":"Department of Medical and Surgical Sciences (DiSCOG), University of Padua, 35100 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7931-0084","authenticated-orcid":false,"given":"Loris","family":"Bertazza","sequence":"additional","affiliation":[{"name":"Endocrinology Unit, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fiammetta","family":"Battheu","sequence":"additional","affiliation":[{"name":"Endocrinology Unit, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5821-2693","authenticated-orcid":false,"given":"Susi","family":"Barollo","sequence":"additional","affiliation":[{"name":"Endocrinology Unit, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7550-8461","authenticated-orcid":false,"given":"Marta","family":"Camilot","sequence":"additional","affiliation":[{"name":"Department of Paediatrics, Regional Centre for Newborn Screening, Diagnosis and Treatment of Inherited Metabolic Diseases and Congenital Endocrine Diseases, Azienda Ospedaliera Universitaria Integrata, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2615-8001","authenticated-orcid":false,"given":"Caterina","family":"Mian","sequence":"additional","affiliation":[{"name":"Endocrinology Unit, Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"404","DOI":"10.1210\/edrv.18.3.0300","article-title":"The Regulation of Thyroid Function in Pregnancy: Pathways of Endocrine Adaptation from Physiology to Pathology","volume":"18","author":"Glinoer","year":"1997","journal-title":"Endocr. 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