PGF and HELLP syndrome: The imbalance between placenta-derived anti-angiogenic factors, notably the soluble fms-Like Tyrosine Kinase 1 (sFLT1) and soluble endoglin (sEnd), and angiogenic proteins as placental growth factor (PlGF), represents a critical event in the pathogenesis of both PE (86, 87) and HELLP syndrome (88).