Inherited Coagulation Dysfunction and Postpartum Hemorrhage
Abstract Number: T-20
Abstract Type: Original Research
Postpartum hemorrhage is the leading cause of death during childbirth as well as the source of significant postpartum morbidity. The incidence rate of postpartum hemorrhage and subsequent blood transfusion appear to have doubled over the last decade. Inherited coagulation defects can potentially cause or worsen postpartum hemorrhage. While it is estimated that 3 million American women have an inherited coagulation defect, most are undiagnosed. This study is designed to determine whether unrecognized inherited coagulation defects may be a contributory factor to this hemorrhage increase.
The pharmacy information system at Magee-Womens Hospital of UPMC was queried as to all women who had received carboprost tromethamine for postpartum hemorrhage since 2005. Carboprost is considered a third line therapy for postpartum hemorrhage. After enrollment, a home visit was made by a clinical research nurse, during which a medical history and blood samples were obtained and a bleeding survey was completed. A control group of patients who did not have postpartum hemorrhage was also enrolled. Blood samples were evaluated for PT/PTT, fibrinogen, thrombin time, Factors II, V, VII, VIII, IX, X, XI, XII, XIII, vWF antigen, and vWF ristocetin cofactor. Platelet function assays were performed but not included in this analysis. An unpaired T-test was used to compare across all testing, with a p-value < 0.05 considered statistically significant.
To date, 91 patients who have suffered postpartum hemorrhage and 169 controls have been enrolled. Patient ages were 31.37 ± 6.65 and 31.53 ± 5.77 (P = 0.8353) for the cases and controls respectively. No differences were found between the cases and controls with two exceptions, Factors II and VII. Factor II levels were 111.9 ± 2.20 and 106.7 ± 1.23 (p = 0.0246) for the cases and controls, respectively. Factor VII levels were 127.4 ± 10.74 and 106.7 ± 2.14 (p = 0.0145) for the cases and controls, respectively. Despite these differences, both means are within normal limits (Factor II normal 82-144 IU/dL; Factor VII normal 64-151 IU/dL).
While the incidence rates of postpartum hemorrhage are increasing, both nationally and at our facility, it appears that the role of inherited coagulation dysfunction in this phenomenon is not significant. This hemorrhage increase more likely relates to uterine mechanical issues. Total enrollment for the study is anticipated to include 400 patients by its conclusion, so differences may be apparent at the completion of enrollment.