Severe thrombocytopenia in a pregnant patient with platelet-associated IgM, and known von Willebrand's disease; a case report.

In this report, a patient with known von Willebrand's disease is presented with severe thrombocytopenia developing during pregnancy, which at first was believed to be caused by immune thrombocytopenic purpura. For several reasons this first diagnosis had to be rejected, but subtyping of von Willebrand's disease pointed out that the patient suffered from type IIB, which, according to recent literature, can lead to platelet destruction in pregnancy. Early subtyping of von Willebrand's disease can have a major influence on the management of pregnancy.