Studies on atihemophilic factor (AHF, factor VIII) during labor in normal women, in patients with premature separation of the placenta, and in a patient with von Willebrand's disease

Abstract

Abstract In patients with the hemorrhagic state associated with premature separation of the placenta and evidences of intravascular clotting, the titer of antihemophilic factor (AHF, factor VIII) clot-promoting activity was grossly reduced without similar depression of AHF-like antigen. Similar, but less extensive changes were observed in some, but not all women undergoing normal labor and delivery. In a patient with von Willebrand's disease, levels of clot-promoting activity and AHF-like antigen rose together during pregnancy to values normal for nonpregnant women, but the bleeding time remained prolonged even when these elevations were most pronounced just before labor.