The authors aimed to determine whether clinical findings of preeclampsia predict magnetic resonance imaging (MRI) diagnosis of posterior reversible encephalopathy syndrome (PRES). The course among preeclamptics/eclamptics with clinically suspected PRES with vs without MRI diagnosis of PRES was compared. Of 46 patients who underwent MRI (eight eclamptics, 38 preeclamptics), five eclamptics (62.5%) and four preeclamptics (10.5%) had confirmed PRES (P=.004). Patients with PRES were younger (26 years vs 31 years, P=.008) and had a higher prevalence of thrombocytopenia (33% vs 8%, P=.04), a greater prevalence of proteinuria (100% vs 61%, P=.04), and higher peak systolic and diastolic blood pressures (P<.05). As opposed to findings from previous reports, PRES was not seen uniformly among eclamptic women and was found in 10.5% of preeclamptics with clinical suspicion of PRES in this study. Given that no single or set of findings were reliable predictors of PRES, consideration for rigorous management of hypertension should be applied to all patients with preeclampsia and eclampsia.