Adverse maternal and neonatal effects associated with perinatal xylazine exposure: a systematic review

Perinatal opioid exposure is increasingly studied, though our understanding of xylazine, a veterinary sedative-turned-fentanyl adulterant, is less robust. The majority of published xylazine data is animal-derived, despite broader drug testing that identifies increased incidental human exposure and prolonged sedation. Xylazine's clinical sequelae are often underrecognized, especially in pregnant populations. We systematically reviewed five databases for literature on xylazine exposure in human pregnancy. We identified eleven discrete reports, where seven described clinical outcomes, and four measured toxicology data indicating xylazine exposure. In both categories, most studies focused on fetal outcomes and umbilical cord tissue testing, which highlighted xylazine transmission to the fetus. Only three studies reported any data on maternal outcomes. Findings suggest that not only is human-derived data on xylazine exposure limited, but maternal outcomes are particularly understudied despite evidence of prevalent exposure.