Prenatal exposure to pesticides and the risk of male genital malformations: a scoping review.

Hypospadias and undescended testis (UDT) are common genital malformations with multifactorial origins. Endocrine-disrupting chemicals, including pesticides, are suspected contributors, but prior reviews are outdated, and none has mapped evidence for both conditions together. To map evidence on the association between prenatal pesticide exposure and hypospadias/UDT, with particular attention to underexplored exposures such as pyrethroids and household pesticides, and to identify research gaps. Following PRISMA-ScR guidance, we searched PubMed, Web of Science, Cochrane, and Embase from 2003 to 2024. Eligible items were original human studies and reviews. Study selection and data extraction were performed by two reviewers. We included 117 articles (62 case-control studies, 7 population-based/cohort/epidemiological studies, 4 meta-analyses, and 44 reviews). Evidence from primary studies was heterogeneous across designs, but several signals recurred: increased risks associated with maternal occupational or residential exposure in agricultural settings; positive associations when exposure was assessed using bioaccumulative matrices (placenta, breast milk, meconium); and limited or null findings with single time-point blood/urine measures. Data on household insecticides use remain scarce, particularly for pyrethroid insecticides. Few studies examined gene–environment interactions. This scoping review highlights suggestive but inconsistent evidence that prenatal pesticide exposure contributes to hypospadias/UDT, with organochlorines (e.g., DDT/DDE, atrazine) most frequently implicated. Key gaps include pyrethroid exposure, prospective designs with improved exposure assessment, and stronger links between human epidemiological findings and existing mechanistic evidence. While causal inference is limited in a scoping review framework, the overall body of evidence supports adopting a precautionary approach to minimizing pesticide exposure during pregnancy. • Residential exposure in agricultural areas frequently reported as associated with higher risk • Most consistent signals found for organochlorines (e.g. DDT/DDE, atrazine) in exposed populations • Bioaccumulative matrices (placenta, breast milk, meconium) tend to yield more consistent associations • Data on household pesticides and pyrethroids remain limited and heterogeneous