Type 1 von Willebrand disease (type 1 VWD) is a form of VWD characterized by a bleeding disorder associated with a partial quantitative plasmatic deficiency of an otherwise structurally and functionally normal Willebrand factor (von Willebrand factor; VWF). The disease is Monarch Disease Ontology identifier MONDO_0008668 (von Willebrand disease 1). Also known as: VWD type 1, VWD1, von Willebrand disease type 1, von Willebrand disease type I, von Willebrand's disease type 1, von willebrand's disease 1.