RecruitingClinical trialVon Willebrand Factor in Pregnancy (VIP) StudyIn pregnant women with von Willebrand disease (VWD) who by the third trimester do not have von Willebrand factor (VWF) or factor VIII (FVIII) levels greater than 50-100%, specific guidance is lacking for delivery planning in terms of how high of a VWF level should be achieved to reduce bleeding. This is a prospective, open-label, cohort study in women with VWD using Wilate VWF replacement therapy to maintain trough or minimum VWF levels of 100-150% for delivery and the immediate postpartum period, followed by levels of 50-100% for 5-10 days after delivery, depending upon the route of delivery. The primary objective is to document the rate of primary postpartum hemorrhage (PPH). The secondary objective is to document further effectiveness outcomes and safety.