<i>Prevotella loescheii</i> attenuates pregnancy‐induced hypertension by reshaping placental immunity and halting macrophage pyroptosis

Abstract Pregnancy‐induced hypertension (PIH) severely impairs placental function, yet its microenvironmental alterations and potential interventions remain unclear. Here, we combined single‐cell RNA sequencing (scRNA‐seq) with an in vivo model to investigate the protective effects of Prevotella loescheii (PL) in PIH. scRNA‐seq revealed that PIH reshaped placental cellular composition, reducing trophoblasts and myeloid cells while increasing smooth muscle cells, and disrupted cell–cell communication. Functional analyses identified oxidative stress (OS) and macrophage‐driven pyroptosis via the NLRP3 inflammasome as key pathological features. Trajectory analysis further demonstrated the depletion of Hofbauer cells, which was restored by PL. In vivo, PL significantly alleviated PIH phenotypes, including proteinuria and placental structural damage. Mechanistically, PL reduced proinflammatory cytokines, suppressed mitochondrial OS and pyroptosis, and partially restored short‐chain fatty acid metabolism. Collectively, these findings indicate that PL ameliorates PIH by modulating the placental immune microenvironment and metabolic homeostasis, providing a potential therapeutic strategy.