{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T13:03:29Z","timestamp":1784811809946,"version":"3.55.0"},"reference-count":39,"publisher":"Wiley","issue":"5","license":[{"start":{"date-parts":[[2021,8,13]],"date-time":"2021-08-13T00:00:00Z","timestamp":1628812800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"},{"start":{"date-parts":[[2021,8,13]],"date-time":"2021-08-13T00:00:00Z","timestamp":1628812800000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100000024","name":"Canadian Institutes of Health Research","doi-asserted-by":"publisher","award":["PJT156025"],"award-info":[{"award-number":["PJT156025"]}],"id":[{"id":"10.13039\/501100000024","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bpspubs.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Pharmacology Res &amp;amp; Perspec"],"published-print":{"date-parts":[[2021,10]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Our study aimed to describe levothyroxine prescription patterns and trends over time among pregnant women with subclinical hypothyroidism (SCH) in the United Kingdom.<\/jats:p>\n                  <jats:p>We used data from the Clinical Practice Research Datalink linked to its Pregnancy Register and the Hospital Episode Statistics database from 1998 to 2017. The study population included women with a diagnosis of SCH or an abnormal thyroid\u2010simulated hormone (TSH) level one\u00a0year prior to or during pregnancy. We compared characteristics between women who received a prescription for levothyroxine during pregnancy and those who did not. We further described the timing, dose, duration, and temporal trends of levothyroxine prescriptions.<\/jats:p>\n                  <jats:p>Our cohort included 6,757 pregnancies from 6,287 women with SCH, of whom 10% received levothyroxine during pregnancy. Among women who received levothyroxine, most received their first prescription during the first trimester (median gestational age: 7\u00a0weeks; interquartile range [IQR]: 0, 16) with a median daily dosage of 50\u00a0mcg (IQR: 50, 73). Levothyroxine prescription varied over time, decreasing from 23% of pregnant women in 1998 to 7.5% in 2003, remaining stable until 2014, and increasing to 12.5% in 2016. Smoking, diabetes, polycystic ovary syndrome, infertility, timing of SCH diagnosis, age, TSH level at diagnosis, and general practice regions were associated with prescription.<\/jats:p>\n                  <jats:p>Few women with SCH received levothyroxine during pregnancy, and treatment varied by patient characteristics and geographical regions. These results highlight the need to increase awareness among healthcare providers and will guide future studies that explore barriers to initiating levothyroxine treatment for women with SCH during pregnancy.<\/jats:p>","DOI":"10.1002\/prp2.848","type":"journal-article","created":{"date-parts":[[2021,8,14]],"date-time":"2021-08-14T01:32:25Z","timestamp":1628904745000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Use of levothyroxine among pregnant women with subclinical hypothyroidism in the United Kingdom: A population\u2010based assessment"],"prefix":"10.1002","volume":"9","author":[{"given":"Ya\u2010Hui","family":"Yu","sequence":"first","affiliation":[{"name":"Department of Epidemiology, Biostatistics and Occupational Health McGill University  Montreal Quebec Canada"},{"name":"Centre for Clinical Epidemiology Lady Davis Institute Jewish General Hospital  Montreal Quebec Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6055-0088","authenticated-orcid":false,"given":"Kristian B.","family":"Filion","sequence":"additional","affiliation":[{"name":"Centre for Clinical Epidemiology Lady Davis Institute Jewish General Hospital  Montreal Quebec Canada"},{"name":"Departments of Medicine and of Epidemiology, Biostatistics and Occupational Health McGill University  Montreal Quebec Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pauline","family":"Reynier","sequence":"additional","affiliation":[{"name":"Centre for Clinical Epidemiology Lady Davis Institute Jewish General Hospital  Montreal Quebec Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5981-8443","authenticated-orcid":false,"given":"Robert W.","family":"Platt","sequence":"additional","affiliation":[{"name":"Centre for Clinical Epidemiology Lady Davis Institute Jewish General Hospital  Montreal Quebec Canada"},{"name":"Departments of Pediatrics and of Epidemiology, Biostatistics and Occupational Health McGill University  Montreal Quebec Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oriana H. Y.","family":"Yu","sequence":"additional","affiliation":[{"name":"Centre for Clinical Epidemiology Lady Davis Institute Jewish General Hospital  Montreal Quebec Canada"},{"name":"Division of Endocrinology Jewish General Hospital  Montreal Quebec Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8576-7854","authenticated-orcid":false,"given":"Sonia M.","family":"Grandi","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, Biostatistics and Occupational Health McGill University  Montreal Quebec Canada"},{"name":"Centre for Clinical Epidemiology Lady Davis Institute Jewish General Hospital  Montreal Quebec Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2021,8,13]]},"reference":[{"key":"e_1_2_12_2_1","doi-asserted-by":"publisher","DOI":"10.1159\/000362597"},{"key":"e_1_2_12_3_1","doi-asserted-by":"publisher","DOI":"10.1093\/humupd\/dmr024"},{"key":"e_1_2_12_4_1","doi-asserted-by":"publisher","DOI":"10.1089\/thy.2015.0418"},{"key":"e_1_2_12_5_1","doi-asserted-by":"publisher","DOI":"10.1089\/thy.2016.0457"},{"issue":"5","key":"e_1_2_12_6_1","first-page":"CD007752","article-title":"Interventions for clinical and subclinical hypothyroidism pre\u2010pregnancy and during pregnancy","author":"Reid SM","year":"2013","journal-title":"Cochrane Database Syst Rev"},{"key":"e_1_2_12_7_1","doi-asserted-by":"publisher","DOI":"10.1093\/humupd\/dms052"},{"key":"e_1_2_12_8_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00404-019-05245-2"},{"key":"e_1_2_12_9_1","doi-asserted-by":"publisher","DOI":"10.1210\/jc.2011-2803"},{"key":"e_1_2_12_10_1","doi-asserted-by":"publisher","DOI":"10.1089\/thy.2011.0087"},{"issue":"3","key":"e_1_2_12_11_1","first-page":"322","article-title":"Effects of maternal subclinical hypothyroidism on obstetrical outcomes during early pregnancy","volume":"35","author":"Wang S","year":"2012","journal-title":"J Endocrinol Invest"},{"key":"e_1_2_12_12_1","doi-asserted-by":"publisher","DOI":"10.1089\/thy.2016.0014"},{"key":"e_1_2_12_13_1","first-page":"356","article-title":"Thyroid hormone treatment among pregnant women with subclinical hypothyroidism: US national assessment","volume":"25","author":"Maraka S","year":"2017","journal-title":"BMJ"},{"issue":"9","key":"e_1_2_12_14_1","first-page":"3893","article-title":"Variation in treatment practices for subclinical hypothyroidism in pregnancy: US national assessment","volume":"104","author":"Maraka S","year":"2019","journal-title":"J Clin Endocrinol Metab"},{"key":"e_1_2_12_15_1","doi-asserted-by":"publisher","DOI":"10.1093\/ije\/dyv098"},{"key":"e_1_2_12_16_1","doi-asserted-by":"publisher","DOI":"10.1002\/pds.4811"},{"key":"e_1_2_12_17_1","unstructured":"English indices of deprivation 2015(access at 1\/14\/2021). 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