Strand-specific viral transcriptomics confirmed the ambisense S segment and revealed preferential transcription of the M and S segments over L. RVFV induced G1 arrest, impairing trophoblast proliferation and differentiation, and drove widespread transcriptional reprogramming, including strong interferon lambda 1 (<i>IFNL1</i>) but modest type I interferon responses, and dysregulation of inflammatory and preeclampsia-associated genes such as <i>RUNX1</i> and <i>TGFBRAP1</i>. Here, IFNL1 is linked to preeclampsia.