{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T11:00:46Z","timestamp":1784718046625,"version":"3.55.0"},"reference-count":27,"publisher":"Bioscientifica","issue":"7","license":[{"start":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T00:00:00Z","timestamp":1783382400000},"content-version":"vor","delay-in-days":6,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["journals.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,7,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The management of subclinical hypothyroidism with thyroid-stimulating hormone (TSH) levels between 2.5 and 4.0 mIU\/L in women with recurrent pregnancy loss (RPL) remains controversial, as guidelines derived from general populations conflict. While a recent randomized trial confirmed the benefit of initiating levothyroxine (LT4) during early pregnancy, whether a more proactive strategy of preconception thyroid optimization improves outcomes in this high-risk group remains unknown.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a retrospective cohort analysis of 896 women with RPL and elevated TSH (2.5\u20134.0 mIU\/L) during pre-pregnancy, from the Recurrent Pregnancy Loss Cohort Study. Based on clinical records, participants were categorized into two groups: treated group (n = 636) and untreated group (n = 260). The primary outcome was miscarriage. Associations were assessed using Firth\u2019s penalized-likelihood regression to address small-sample bias, with propensity score matching as a sensitivity analysis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>After adjustment for antiphospholipid syndrome, degree of education, gravidity, and parity, LT4 treatment was associated with a significantly lower risk of miscarriage (adjusted odds ratio (aOR) = 0.33; 95% CI: 0.20, 0.54; P &amp;lt; 0.001). A reduced risk was also observed for threatened abortion (aOR = 0.49; 95% CI: 0.35, 0.71; P &amp;lt; 0.001). Results were robust in the propensity score-matched analysis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>In women with RPL and elevated TSH (2.5\u20134.0 mIU\/L), a clinical care pathway involving preconception LT4 treatment was significantly associated with a reduced risk of miscarriage. This finding provides real-world evidence supporting the potential value of proactive preconception thyroid optimization in RPL, highlighting it as a priority strategy worthy of prospective investigation versus post-conception treatment initiation.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1530\/ec-26-0215","type":"journal-article","created":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T10:01:47Z","timestamp":1784714507000},"update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-10","source":"Crossref","is-referenced-by-count":0,"title":["Preconception thyroid function optimization and pregnancy outcomes in women with recurrent pregnancy loss: a real-world cohort study"],"prefix":"10.1530","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8411-0922","authenticated-orcid":true,"given":"Heze","family":"Xu","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University 1 , , ,","place":["Shenyang, Liaoning Province, China"]},{"name":"Key Laboratory of Maternal-Fetal Medicine of Liaoning Province 2 , , ,","place":["Shenyang, Liaoning, China"]},{"name":"Research Center of China Medical University Birth Cohort 3 , , ,","place":["Shenyang, Liaoning Province, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhijiao","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University 1 , , ,","place":["Shenyang, Liaoning Province, China"]},{"name":"Key Laboratory of Maternal-Fetal Medicine of Liaoning Province 2 , , ,","place":["Shenyang, Liaoning, China"]},{"name":"Research Center of China Medical University Birth Cohort 3 , , ,","place":["Shenyang, Liaoning Province, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yijia","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University 1 , , ,","place":["Shenyang, Liaoning Province, China"]},{"name":"Key Laboratory of Maternal-Fetal Medicine of Liaoning Province 2 , , ,","place":["Shenyang, Liaoning, China"]},{"name":"Research Center of China Medical University Birth Cohort 3 , , ,","place":["Shenyang, Liaoning Province, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shanwei","family":"Xing","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University 1 , , ,","place":["Shenyang, Liaoning Province, China"]},{"name":"Key Laboratory of Maternal-Fetal Medicine of Liaoning Province 2 , , ,","place":["Shenyang, Liaoning, China"]},{"name":"Research Center of China Medical University Birth Cohort 3 , , ,","place":["Shenyang, Liaoning Province, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hang","family":"Zhen","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University 1 , , ,","place":["Shenyang, Liaoning Province, China"]},{"name":"Key Laboratory of Maternal-Fetal Medicine of Liaoning Province 2 , , ,","place":["Shenyang, Liaoning, China"]},{"name":"Research Center of China Medical University Birth Cohort 3 , , ,","place":["Shenyang, Liaoning Province, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiapo","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Shengjing Hospital, China Medical University 1 , , ,","place":["Shenyang, Liaoning Province, China"]},{"name":"Key Laboratory of Maternal-Fetal Medicine of Liaoning Province 2 , , ,","place":["Shenyang, Liaoning, China"]},{"name":"Research Center of China Medical University Birth Cohort 3 , , ,","place":["Shenyang, Liaoning Province, 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