{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T17:25:56Z","timestamp":1790184356241,"version":"4.1.0"},"reference-count":47,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,2,25]],"date-time":"2021-02-25T00:00:00Z","timestamp":1614211200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Endocrinol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Iron deficiency (ID) is concerned as the most common nutritional deficiency worldwide. The effects of ID on thyroid function and autoimmunity in pregnant women and reproductive-age women are controversial. The aim of the current study was to summarize the evidences and evaluate the relationship between ID and thyroid disorders.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In this systematic review and meta-analysis, studies published on the Cochrane, Embase, Medline, and PubMed databases by October 2020 were searched. A total of 636 studies which discussed the correlation between ID and thyroid disorders were eligible in the initial search. Pooled mean differences (MD) and 95% confidence intervals (CI) were calculated for the assessment of thyrotropin (TSH) and free thyroxine (FT4) levels. Combined odd ratios (OR) and 95% CI were calculated for the assessment of the prevalence of overt and subclinical hypothyroidism, positive thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      For women of reproductive age, ID could significantly increase the risk of positive TPOAb (OR: 1.89; 95% CI: 1.17, 3.06:\n                      <jats:italic>P<\/jats:italic>\n                      = 0.01) and both positive TPOAb and TgAb (OR: 1.48; 95% CI: 1.03, 2.11:\n                      <jats:italic>P<\/jats:italic>\n                      = 0.03). The meta-analysis of pregnant women showed that pregnant women with ID had increased serum TSH levels (MD: 0.12; 95% CI: 0.07, 0.17; P &amp;lt; 0.00001) and decreased FT4 levels (MD: \u22120.73; 95% CI: \u22121.04, \u22120.41; P &amp;lt; 0.00001). Meanwhile, the prevalence of overt (OR: 1.60; 95% CI: 1.17, 2.19; P = 0.004) and subclinical (OR: 1.37; 95% CI: 1.13, 1.66; P = 0.001) hypothyroidism in pregnant women with ID was significantly increased.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>ID may adversely affect thyroid function and autoimmunity of pregnant and reproductive-age women and it is very necessary for monitoring iron nutritional status and early treatment of ID for them.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fendo.2021.629831","type":"journal-article","created":{"date-parts":[[2021,2,25]],"date-time":"2021-02-25T04:14:13Z","timestamp":1614226453000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":52,"title":["Iron Deficiency, a Risk Factor of Thyroid Disorders in Reproductive-Age and Pregnant Women: 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