Endoplasmic reticulum (ER) stress-induced apoptosis has been implicated in severe pre-eclampsia (SPE) and is characterized by the activation of three signaling pathways: PKR-like endoplasmic reticulum kinase (PERK), activating transcription factor 6 (ATF6), and inositol-requiring 1 (Ire1). This study was designed to investigate the role of ER stress in the pathogenesis of SPE.