Pesticide exposure during pregnancy and the risk of adverse maternal and fetal outcomes: a systematic review.

BACKGROUND: Pesticides are widely used in agriculture, residential settings, and public spaces, leading to environmental contamination and human exposure. During pregnancy, these compounds may cross the placenta and affect both maternal and fetal health. However, epidemiological evidence remains inconsistent and often focuses on specific pesticide classes or isolated reproductive outcomes. OBJECTIVES: To systematically review and synthesize observational evidence on associations between maternal exposure to currently used pesticide classes and maternal and fetal outcomes. METHODS: A systematic search was conducted in PubMed, Web of Science, Scopus, and ScienceDirect from inception to November 14, 2025. During screening, studies assessing pesticide exposure prior to 2000 were excluded due to regulatory restrictions over recent decades. Eligible studies measured prenatal pesticide exposure using biological samples and reported maternal or fetal outcomes. Three reviewers independently screened and extracted data. Risk of bias was assessed using the NHLBI quality assessment tools. The protocol was registered in PROSPERO (CRD420251172677). RESULTS: Of 6,776 records identified, 39 studies including 24,532 participants from 17 countries and territories met the inclusion criteria. Exposure to organophosphate pesticides (OPs) was associated with impaired fetal growth in several studies, with evidence pointing to trimester- and sex-specific effects. Associations with shortened gestational duration and increased risk of preterm birth were also reported, particularly for OPs and glyphosate. Evidence for neonicotinoid exposure and gestational diabetes mellitus was suggestive, but derived exclusively from Chinese cohorts, limiting generalizability. CONCLUSION: Maternal exposure to currently used pesticides during pregnancy may be associated with fetal growth outcomes and maternal health. Future research should prioritize repeated biomarker measurements and mixture modelling to improve the characterization of potential reproductive health effects associated with these pesticides.