PGF and preeclampsia: In a developing preeclampsia, a distortion is observed of the proportions between angiogenic factors, such as vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) on the one hand and anti-angiogenic factors (i.e., soluble fms-like tyrosine kinase-1(sFlt-1) and endoglin (sEng)) on the other.