CX3CL1 and preterm premature rupture of the membranes: CX3CL1 has been reported as a promising blood biomarker in the prediction of PPROM in the first trimester.[15] El-Achi et al reported that biomarkers measured during first-trimester screenings like pregnancy-associated plasma protein-A (PAPP-A), and βHCG did not predict PPROM.