The Course of von Willebrand Factor and Factor VIII Activity in Patients with von Willebrand Disease during Pregnancy.

INTRODUCTION: Women with von Willebrand disease (VWD) are at a higher risk of bleeding, which might affect the health of mother and child during pregnancy and the intra- and postpartum periods. This retrospective cohort study evaluates changes in the coagulation parameters von Willebrand factor antigen (VWF:Ag), von Willebrand ristocetin cofactor (VWF:RCo), and Factor VIII activity (FVIII:C) during pregnancy in patients with VWD. In total, 44 pregnancies of 38 patients were assessed (VWD type 1 n = 32, type 2A n = 3, type 2B n = 1, type 2 subtype unidentified n = 2). The patients' median age at childbirth was 32 years (range 22-40).

RESULTS: A significant increase in coagulation parameters was found in patients with VWD type 1 (VWF:Ag, VWF:RCo, and FVIII:C p = 0.000). In the third trimester, VWF:Ag and FVIII:C normalized in all patients with VWD type 1; in 3 patients VWF:RCo remained below the normal range. Patients with VWD type 2 showed a significant increase of VWF:Ag (p = 0.003) and FVIII:C (p = 0.011), and a non-significant increase of VWF:RCo (p = 0.097). In 4 of 9 pregnancies of patients with VWD type 2, all surveyed coagulation parameters normalized until the third trimester.

CONCLUSION: For the majority of the observed patients, the von Willebrand parameters increased during pregnancy.