Activation contact system (ACS) and tissue factor (TF) in human amniotic fluid: Measurements of ACS components and TF, and some implications on the pathophysiology of amniotic fluid embolism

1.The ACS components, i.e. FXII, FXI, PK and HMWK, are the constituents of amniotic fluid. 2.The concentrations of the amniotic fluid-derived factors having a coagulation initiation potential, i.e. TF and contact phase coagulation factors, are higher in amniotic fluid than in mother's blood plasma.