Evidence map›Paper›PMID 42850623›Full record

ArticleBMC endocrine disorders2026

Association of dietary iron intake and serum iron with self-reported history of pregnancy loss among women: a cross-sectional study based on NHANES 2005-2018.

Huiyan Cao, Yanping Tao

Abstract read
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Article in BMC endocrine disorders, 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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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

2 authors.

Huiyan CaoDepartment of Obstetrics, Hangzhou Maternity and Child Health Care Hospital, No. 369 Kunpeng Road, Shangcheng District, Hangzhou, Zhejiang, 310000, China.
Yanping TaoDepartment of Obstetrics, Hangzhou Maternity and Child Health Care Hospital, No. 369 Kunpeng Road, Shangcheng District, Hangzhou, Zhejiang, 310000, China. yanpingtao455@163.com.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveAbnormal iron metabolism has been suggested to be associated with pregnancy loss. However, dietary iron intake and serum iron levels reflect different aspects of iron metabolism, and their respective relationships with pregnancy loss remain unclear. This study aimed to investigate the associations of dietary iron intake and serum iron levels with self-reported history of pregnancy loss among women aged 20-50 years using data from the National Health and Nutrition Examination Survey (NHANES) 2005-2018.

methodsAnalyses were conducted based on the NHANES 2005-2018 dataset. Weighted logistic regression models were applied to examine the relationships between dietary iron intake, serum iron concentrations, and the prevalence of self-reported history of pregnancy loss. Restricted cubic spline regression was utilized to characterize the dose‑response associations among these indicators. Additionally, subgroup stratification analysis and sensitivity analysis were further carried out to verify the stability and reliability of the findings.

resultsA total of 3,417 women aged 20-50 years were included in the final analysis. In the fully adjusted weighted logistic regression model, dietary iron intake was negatively associated with self-reported history of pregnancy loss (OR = 0.975, 95% CI: 0.953-0.999, P = 0.038), whereas serum iron levels were positively associated with self-reported history of pregnancy loss (OR = 1.028, 95% CI: 1.007-1.049, P < 0.001). Restricted cubic spline analysis revealed a linear negative association between dietary iron intake and self-reported pregnancy loss (P overall < 0.001) and a linear positive association between serum iron levels and self-reported pregnancy loss (P overall = 0.003). Subgroup analysis, showed a significant interaction between oral contraceptive use history and serum iron levels (P for interaction = 0.016). Sensitivity analyses supported the robustness of the findings.

conclusionThis cross‑sectional investigation enrolled American women aged 20-50 years. The results indicated that dietary iron intake was inversely correlated with self-reported history of pregnancy loss, whereas serum iron concentrations displayed a positive correlation with such medical history, presenting opposite association trends. A notable interactive effect was identified between oral contraceptive use history and serum iron levels. Given the inherent limitations of the cross‑sectional design, causal inference could not be established in the present study. Further prospective cohort studies are therefore required to corroborate these observations.

Indexed as

Abortion, SpontaneousIronIron, DietaryAdultCross-Sectional StudiesFemaleFollow-Up StudiesHumansMiddle AgedNutrition SurveysPregnancyPrognosisSelf ReportYoung AdultIronIron, DietaryDietary iron intakeNHANESPregnancy lossSerum iron

Identifiers

PMID42850623
PMCPMC13647559

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.