Value of Placental Volume and Vascular Flow Indices as Predictors of Early and Late Preeclampsia at First Trimester

Abstract

Introduction: We evaluated the utility of placental volume and three-dimensional (3D) vascular flow indices to predict early and late preeclampsia. Material and Methods: In 1,004 pregnancies attending routine care, we recorded first-trimester screening program for aneuploidy (FTSA) parameter and measured uterine artery pulsatility index (uterine-a PI). Placental volume and vascular flow indices were obtained using 3D power Doppler and VOCAL techniques. Results: Placental volume was lower and uterine-a PI was higher in both early and late preeclampsia groups versus nonaffected pregnancies. The prediction rate of placental volume in late preeclampsia was higher than that of uterine-a PI (AUROC 0.707 vs. 0.581, p < 0.011). The inclusion of placental volume improved significantly the prediction rate of total and late preeclampsia in the models constructed with maternal characteristics, FTSA, and uterine-a PI (AUROC 0.745 vs. 0.818, p < 0.004, and 0.740 vs. 0.812, p < 0.012, respectively). The inclusion of vascular indices did not improve the predictive value of these models. Discussion: Placental volume was an independent predictor of total, early, and late preeclampsia and its inclusion in combined predictive models significantly improved prediction rates. Reduced placental volume observed at first trimester in women with early and late preeclampsia suggests that these entities are the clinical expression of a similar pathophysiological process.