PGF and hypertensive disorder: As such, it is becoming clear by the results of the aforementioned studies and our meta-analysis that PAPP-A is a poor marker of the subsequent development of hypertensive disorders of pregnancy, and future studies should mostly focus on assays such as the soluble fms-like tyrosine kinase-1 (sFlt-1) and the placental growth factor (PLGF) [33].