Background: Although studies have suggested an association between organic solvent exposure and small-for-gestational age (SGA), conclusions remain inconsistent due to variations in sample size and study design, with insufficient epidemiological evidence.
Objective: We investigated the association between organic solvent exposure and SGA.
Methods: Following the PRISMA guidelines, searched PubMed, MEDLINE, Embase, and Science Direct databases for cohort and case-control studies. Exposure was classified based on job-exposure matrices (JEMs), expert assessment, or self-reported history. SGA was defined as birth weight <10th centile for gestational age based on a national reference. This systematic review included a total of 11 eligible articles, comprising 15 independent observational studies, of which 10 were cohort studies and 5 were case-control studies. The quality of included studies was assessed using the Newcastle-Ottawa Scale (NOS). Statistical analyses were performed using STATA 14.0 software to calculate the pooled odds ratio (OR) and 95% confidence interval (CI). Heterogeneity was evaluated via Cochran's Q test and I² statistic, with subgroup analysis, sensitivity analysis, and publication bias testing conducted.
Results: Pooled analysis showed that organic solvent exposure was associated with a slight increase in the risk of SGA (OR = 1.15, 95% CI: 1.04-1.26), with moderate heterogeneity (I² = 40.5%, P = 0.052). Subgroup analyses indicated that studies conducted in European and American regions, cohort studies, occupational exposure studies, and high-quality studies (NOS ≥ 7 points) all showed a significant positive association with low heterogeneity (I² = 0), among which the association intensity of occupational exposure was the highest (OR = 1.33). Sensitivity analyses showed that after sequentially excluding each individual study, the pooled OR ranged from 1.12 (95% CI: 1.03-1.22) to 1.19 (95% CI: 1.09-1.29), indicating stable results. Publication bias tests suggested the presence of overall bias (Egger's test P < 0.05), which implies that the pooled effect size might be an overestimation due to the potential absence of small, null-result studies. However, notably, no significant bias was found in the occupational exposure subgroup (Begg's test P = 0.592, Egger's test P = 0.464). Therefore, while the main findings should be interpreted with caution, the results for the occupational exposure subgroup appear to be more robust against publication bias.
Significance: Maternal occupational/environmental exposure to selected organic solvents may increase the risk of small-for-gestational age, especially in occupationally exposed populations.
Impact statement: This systematic review and meta-analysis, which synthesizes evidence from 15 high-quality studies (10 cohort studies and 5 case-control studies) across Europe and the USA, confirms that maternal occupational/environmental exposure to organic solvents is associated with a 15% increased risk of small-for-gestational-age (SGA) births, with the risk being even higher (33% increase) in occupationally exposed populations. This finding carries substantial implications for public health practice, workplace safety policy, and clinical prenatal care, as outlined below.
Keywords: Meta-analysis; Organic solvents; Prenatal exposure; Small-for-gestational age (SGA); Systematic review.
© 2026. The Author(s), under exclusive licence to Springer Nature America, Inc.