Laboratory monitoring during pregnancy and post-partum hemorrhage in women with von Willebrand disease

Background Evidence-based guidelines recommend that von Willebrand factor (VWF) levels be obtained in the third trimester of pregnancy to facilitate peripartum planning for women with von Willebrand disease (VWD). Objectives To identify the frequency of third trimester monitoring in a nationally representative sample of pregnant women with VWD in the United States, as well as the frequency of reproductive bleeding after pregnancy. Patients/Methods Patient data were obtained from the Truven Health MarketScan Research Databases. International Classification of Diseases-9 codes were used to identify women with VWD and evidence of infant delivery. We defined third trimester monitoring as a laboratory claim for VWF levels during the 3 months before delivery. Clinical outcomes studied included postpartum hemorrhage (PPH) and heavy menstrual bleeding (HMB). Results We identified 2238 unique pregnant females with VWD. Of these, 32% (n = 714) underwent third-trimester testing of VWF levels. Diagnostic codes consistent with PPH were recorded for 6.5% of women in the 6 weeks after infant delivery. The frequency of PPH in women who underwent VWF monitoring (4.9%) was significantly lower than in those who did not undergo monitoring (7.3%), (risk difference -2.4%, 95% CI -4.4% to -0.3%, P = .023). Diagnostic codes consistent with HMB were recorded for 4.7% of women in the 3 months after infant delivery. Conclusions Third-trimester VWF monitoring was associated with a lower risk of PPH, but testing was performed in only one-third of insured pregnant women with VWD in the United States despite expert recommendations.