PGF and preeclampsia: In the last decade, studies have found several biomarkers during early pregnancy attempting to predict preeclampsia, including antiangiogenic sFlt-1 (soluble fms-like tyrosine kinase-1) and low levels of proangiogenic PlGF (placenta growth factor protein), the ratio between sFlt-1/PlGF, circulating RNA and cystatin-c [13,21,22,23,24,25].