For FFPE placenta samples, total RNA samples were prepared using the Qiagen RNeasy FFPE kit (Cat# 38673604), followed by DNaseI treatment using manufacturer's instructions. For ex vivo placental cell clusters, total RNA was extracted using Trizol (Thermo Fisher Scientific) followed by ezDNAse treatment (Thermo Fisher Scientific) per manufacturer's instructions. Ex vivo placental cell clusters were further cleaned using RNAClean XP beads (Beckman Coutler) per manufacturer's instructions. RNAseq libraries were prepared using the TruSeq Stranded Total RNA Library Prep Kit (Illumina) according to the manufacturer's instructions.