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.