Obstetric Defibrination Syndrome with Abnormal Thrombin‐Fibrinogen Reaction and Immunologically Reactive Altered Fibrinogen in Serum

The clinical and laboratory features of a patient with the obstetric defibrination syndrome are described. The abnormal bleeding responded to fibrinogen therapy and epsilon-aminocaproic acid was not used. The patient's plasma contained little fibrinogen capable of clotting without protamine and it inhibited the thrombin clotting time of normal plasma. Increased fibrinolysis was not observed. Serum obtained from the plasma after addition of protamine and concentrated thrombin contained a substance which reacted with an anti-fibrin serum when tested by an immunoelectrophoretic technique. The results confirmed that ‘altered’ incoagulable fibrinogen determinants were present in the patient's blood which may have interfered with the thrombin-fibrinogen reaction. It is suggested that these changes may be due to intravascular coagulation and not only to fibrinogenolysis. Similar but less severe coagulation changes were observed in the infant's cord blood.