What is the risk for a pregnant woman with type 2 von Willebrand disease undergoing a dilation and curettage (D&C) of the uterus without treatment for her condition?

Risk Assessment for Untreated Type 2 von Willebrand Disease During Dilation and Curettage in Pregnancy

A pregnant woman with untreated type 2 von Willebrand disease undergoing dilation and curettage (D&C) is at very high risk for significant hemorrhage that could be life-threatening without appropriate hemostatic management.

Understanding the Bleeding Risk

Type 2 von Willebrand disease (VWD) is characterized by qualitative defects in von Willebrand factor (VWF), which plays crucial roles in:

• Primary hemostasis (platelet adhesion)
• Secondary hemostasis (as a carrier protein for Factor VIII)

The specific risks in this scenario include:

1. Baseline hemorrhagic risk: Type 2 VWD patients have dysfunctional VWF, leading to impaired platelet adhesion and potentially reduced Factor VIII levels 1.

2. Pregnancy-specific considerations:

   • While pregnancy normally increases VWF levels in most women, this response is variable in Type 2 VWD 2.
   • Type 2 VWD patients often do not experience the same physiologic increase in functional VWF during pregnancy that Type 1 patients do 3.
   • Type 2B VWD may actually worsen during pregnancy with paradoxical thrombocytopenia 4.

3. Procedure-related risk: D&C is a surgical procedure with significant bleeding risk, involving the highly vascular pregnant uterus.

Risk Stratification by VWD Subtype

Type 2A VWD

• Characterized by decreased high-molecular-weight VWF multimers
• Patients with Type 2A VWD with mutations like V1665E show minimal improvement in VWF activity during pregnancy 2
• High risk for hemorrhage during D&C without treatment

Type 2B VWD

• Characterized by increased affinity of VWF for platelets
• May develop worsening thrombocytopenia during pregnancy 4
• Extremely high risk for hemorrhage during D&C without treatment

Type 2M and 2N VWD

• Type 2M: decreased VWF-platelet interaction without multimer deficiency
• Type 2N: decreased VWF-FVIII binding
• Both carry significant bleeding risk during invasive procedures

Quantifying the Risk

Without treatment, a pregnant woman with Type 2 VWD undergoing D&C faces:

1. Immediate procedural hemorrhage: Very high risk of excessive bleeding during the procedure itself.

2. Delayed postpartum hemorrhage: Significant risk of delayed bleeding even after apparent initial hemostasis 3.

3. Mortality risk: In severe cases, untreated hemorrhage can lead to hypovolemic shock and death.

4. Morbidity risks: Blood transfusion requirements, prolonged hospitalization, and potential need for additional surgical interventions including hysterectomy in extreme cases.

Management Recommendations

Given the high bleeding risk, the following approach is recommended:

1. Pre-procedure assessment:

   • Measure baseline VWF:Ag, VWF:RCo, and FVIII levels 1
   • Determine specific VWD subtype if not already known

2. Hemostatic therapy:

   • For most Type 2 VWD subtypes: VWF/FVIII concentrate is the treatment of choice 1, 2
   • Target VWF activity level of ≥50 IU/dL before procedure 5
   • Desmopressin may be considered for specific subtypes after documented response testing, but is generally less effective in Type 2 VWD 6

3. Monitoring:

   • Close monitoring of VWF and FVIII levels before, during, and after procedure
   • Vigilant observation for bleeding for at least 2 weeks post-procedure 3

4. Extended prophylaxis:

   • Continue hemostatic therapy for at least 7-14 days post-procedure due to risk of delayed hemorrhage 3

Conclusion

The risk of significant hemorrhage for a pregnant woman with untreated Type 2 VWD undergoing D&C is extremely high. Without appropriate hemostatic management, this scenario represents a potentially life-threatening situation that requires immediate intervention with appropriate factor replacement therapy before any surgical procedure is undertaken.