Evidence mapPaperPMID 42101199Full record

ArticleJournal of hypertension2026

Asymmetric U-shaped association between first-trimester maternal free thyroxine levels and the risk of preeclampsia: a large-scale cohort study.

Sha Chen, Xueya Zhao, Lina Xia, Yu Meng

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Article in Journal of hypertension, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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4 · The record

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5 · Who and what money

Authors and funding

4 authors.

Sha ChenDepartment of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University.
Xueya ZhaoDepartment of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University.
Lina XiaDepartment of Obstetrics and Gynecology, Songjiang Maternity & Child Health Hospital of Shanghai, Shanghai, China.
Yu MengDepartment of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveThis study aimed to define the nonlinear relationship between maternal free thyroxine (FT4) levels in early pregnancy and the risk of preeclampsia.

methodsThis study used a large-scale retrospective cohort of 46 592 women with singleton pregnancies. Thyroid function parameters and preeclampsia outcomes were collected. A restricted cubic spline model analyzed the nonlinear relationship between FT4 levels and preeclampsia risk. Odds ratios were calculated using multivariable logistic regression, adjusting for confounders. Preeclampsia risk was also assessed based on thyroid disease classifications. Sensitivity analyses validated the robustness of the results.

resultsThe study found a U-shaped relationship between FT4 levels in early pregnancy and preeclampsia risk. The risk was lowest at 15 pmol/l, with a significant increase as FT4 deviated from this value, especially at lower FT4 levels. A physiological optimal range of 13.9-17.3 pmol/l was identified. Compared to women in this range, low FT4 levels (< 11.7 pmol/l) had a significantly higher risk of preeclampsia (adjusted odds ratio, aOR = 2.23). Even women with FT4 at the lower end of the normal range (11.7-13.9 pmol/l) had increased risk (aOR = 1.26), indicating a latent high-risk group. In traditional thyroid classification, only hypothyroxinemia was a significant independent risk factor. Sensitivity analyses confirmed result stability.

conclusionThis study reveals that low FT4 level is an independent risk factor for preeclampsia, with a dose-dependent effect. These findings support targeted prevention strategies and provide a new approach for precise preeclampsia prevention.

Indexed as

Pre-EclampsiaPregnancy Trimester, FirstThyroxineAdultCohort StudiesFemaleHumansPregnancyRetrospective StudiesRisk FactorsThyroxinecohort studyfirst trimesterfree thyroxinepreeclampsiathyroid-stimulating hormone

Identifiers

PMID42101199
PMCPMC13336680

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