The landmark study that identified the value of this approach was published by Poon et al. in 2009 [38], in which an algorithm incorporating maternal history, uterine artery PI (UtA-PI), mean arterial pressure (MAP), PAPP-A, and PlGF achieved a detection rate for early preeclampsia of 93% at a 5% false positive rate. This evidence concerns the gene PGF and preeclampsia.