PAPPA and preeclampsia: Early statistical models using logistic regression (e.g., the Fetal Medicine Foundation’s first-trimester combined screening test) incorporated clinical, biochemical (Pregnancy-associated Plasma Protein-A, PAPP-A, placental growth factor, PlGF), and biophysical markers (mean arterial pressure, uterine artery Doppler) to achieve high accuracy (AUC ~ 0.90) for early-onset preeclampsia [10,15].