SynthesisBMC pregnancy and childbirth2025
Meta-analysis of maternal exposure to heavy metals (lead, cadmium, mercury, chromium) and adverse pregnancy outcomes.
Synthesis in BMC pregnancy and childbirth, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
3 citing papers in PubMed.
- Moderate Processing of Rice: Processing Technology, Quality Evaluation, and Reflections Precision.Foods (Basel, Switzerland) · 2026Review
- Maternal blood lead levels and proximity to legacy mining contamination in Kabwe, Zambia: socioeconomic disparities and potential implications on fetal health.Environmental science and pollution research international · 2026Article
- Heavy metals detected in fetal and placental tissues in a pregnancy complicated by severe fetal growth impairment and sacrococcygeal teratoma: a case report.Frontiers in toxicology · 2026Article
Corrections and comments
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Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe association of heavy metal exposure with adverse pregnancy outcomes (APOs) remains a subject of debate. The goal of the present study was to analyze the correlation of heavy metals (lead [Pb], cadmium [Cd], mercury [Hg], chromium [Cr]) with APOs.
methodsA systematic review was carried out across four databases: The Cochrane Library, PubMed, Web of Science, and Embase up to November 19, 2024. Two independent researchers performed the literature screening and data extraction based on predefined eligibility criteria. Then, based on the selected literature, the researchers extracted the odds ratios (ORs) and confidence intervals (CIs) of heavy metals (Pb, Cd, Hg, and Cr) and pregnancy outcomes (preterm birth, low birth weight [LBW], and small gestational age [SGA]). The Newcastle-Ottawa Scale (NOS) was adopted for quality assessment. Heterogeneity tests, sensitivity checks, subgroup evaluations, and publication bias analyses were implemented via Stata 15.1 software.
resultsThis meta-analysis incorporated 24 studies, involving 52,390 subjects. The results demonstrated a significant association of Pb concentration with preterm birth (OR = 1.4, 95% CI: 1.17, 1.68; P < 0.001) and SGA (OR = 1.66, 95% CI: 1.04, 2.66; P = 0.034), though not with LBW. Cd concentration was associated with LBW (OR = 1.10, 95% CI: 1.00, 1.20; P = 0.041) and SGA (OR = 1.27, 95% CI: 1.08, 1.48; P = 0.003), but not with preterm birth. No significant association was observed between Hg concentration and preterm birth. Due to insufficient data, the impact of Cr was not analyzed. Subgroup analysis suggested that region, study design, measurement time, and measurement source may influence the conclusions.
conclusionsThis meta-analysis indicated that Pb exposure was associated with elevated risks of both preterm birth and SGA. Cd exposure exhibited significant associations with LBW and SGA. However, the limited number of articles for other indicators warrants further investigation. Future prospective, high-quality studies are encouraged to explore these relationships further.
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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 Socratic graph.