Validation of Boundary Criterion for Predicting Clinical DIC During Delivery on the Fibrinogen–FDP Plane Using Severe Placental Abruption, and Characteristics of Coagulation–Fibrinolytic Activation of Clinical DIC

Background: /Objectives: We have defined severe postpartum hemorrhage (PPH) complicated with hematuria as clinical disseminated intravascular coagulation (DIC) and reported a methodology, using artificial intelligence, for developing the boundary criterion for predicting hematuria on the fibrinogen–fibrin/fibrinogen degradation products (FDP) plane: a positive FDP–fibrinogen/3–60 (mg/dL) value indicates hematuria, otherwise, non-hematuria. We aimed to validate this criterion using severe placental abruption (PA), as the criterion was developed using PPH except for PA, and to examine the coagulation–fibrinolytic system activation in clinical DIC. Methods: Of 17,285 deliveries assessed, 13 had severe PA without hematuria, 18 severe PPH without hematuria, and three severe PPH with hematuria, i.e., clinical DIC. Cases were obtained from nine national perinatal centers in Japan between August 2020 and June 2024. We calculated the values for 13 severe PA cases using the criterion and compared the laboratory tests for coagulation–fibrinolytic activation including thrombin–antithrombin complex (TAT) and plasmin-α2–plasmin inhibitor complex (PIC) among the three groups. Results: The calculated values using the criterion for the 13 PA without hematuria were all negative. In clinical DIC cases, fibrinogen (median, 62 mg/dL) was lower, and FDP (median, 96 mg/dL), TAT (median, 120 ng/mL ), and PIC (median, 28.4 μg/mL) were significantly higher than in the other two groups. Conclusions: The criterion accurately diagnosed all PA without clinical hematuria as non-hematuria. The coagulation–fibrinolysis test results demonstrated the validity of considering cases with hematuria as clinical DIC. The criterion appears useful for diagnosing clinical DIC during delivery.