ArticlePublic health nutrition2020
Preconception Hb concentration with risk of spontaneous abortion: a population-based cohort study in over 3·9 million women across rural China.
Article in Public health nutrition, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers.
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Who cites it
7 citing papers in PubMed.
- Novel proteomics biomarkers of recurrent pregnancy loss reflect the dysregulation of immune interactions at the maternal-fetal interface.Frontiers in immunology · 2025Article
- Risk and protective factors of miscarriage: Evidence from a nationally representative sample of women in India.Journal of family medicine and primary care · 2024Article
- Associations between maternal occupational exposures and pregnancy outcomes among Chinese nurses: a nationwide study.Reproductive health · 2023Article
- Article
- Spatiotemporal Patterns of Adverse Pregnancy Outcomes in Rural Areas of Henan, China.International journal of environmental research and public health · 2022Article
- Nationwide-free preconception care strategy: Experience from China.Frontiers in public health · 2022Review
- High and Low Haemoglobin Levels in Early Pregnancy Are Associated to a Higher Risk of Miscarriage: A Population-Based Cohort Study.Nutrients · 2021Article
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Authors and funding
14 authors.
Funding
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Abstract
objectiveEvidence on the relationship between maternal Hb concentration and spontaneous abortion (SA) risk is limited and conflicting. The purpose of the study was to evaluate whether maternal preconception anaemia or high Hb concentration is associated with risk of SA.
designA population-based cohort study established between 2013 and 2017. SETTINGS: Local maternal and child care service centres in each county.
participantsIn total, 3 971 428 women aged 20-49 years, who participated in National Free Pre-Pregnancy Checkups Project from 2013 to 2016 and successfully got pregnant before 2017 in rural China.
resultsA total of 101 700 (2·56 %) women were recorded having SA, with highest SA rate in women with severe anaemia (4·58 %). Compared with women with Hb of 110-149 g/l, the multivariable-adjusted OR for SA was 1·52 (95 % CI: 1·25, 1·86) for women with Hb < 70 g/l, 0·92 (0·84, 1·01) for 70-99 g/l, 0·80 (0·77, 0·83) for 100-109 g/l, 1·11 (1·08, 1·15) for 150-159 g/l, 1·12 (1·04, 1·20) for 160-169 g/l and 1·02 (0·93, 1·12) for ≥ 170 g/l, respectively. An approximate U-shaped curve for the risk of SA with Hb concentrations was observed when Hb concentrations less than 145 g/l, above which the association plateaued (Pnon-linear < 0·001).
conclusionsSevere anaemia and high Hb concentration before pregnancy were associated with an increased risk of SA. Women with mild anaemia prior to pregnancy had lower risk of SA. Underlying mechanisms need to be further studied.
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