How should prenatal care be managed for a pregnant patient suspected to have Type 2B von Willebrand disease?

Management of Prenatal Care in Suspected Type 2B von Willebrand Disease

Pregnant patients with suspected Type 2B von Willebrand disease should receive specialized prenatal care with close monitoring of VWF parameters and platelet counts throughout pregnancy, with VWF replacement therapy targeting trough levels ≥1.5 g/L during labor and delivery.

Preconception and Early Pregnancy Management

• Preconception counseling is essential for women with suspected Type 2B VWD:

  • Discuss inheritance patterns and risks during pregnancy
  • Formulate a management plan considering clinical phenotype and obstetric history
  • Establish a multidisciplinary team including hematology and high-risk obstetrics

• Laboratory assessment:

  • Confirm diagnosis with VWF parameters and genetic testing if not already done
  • Establish baseline VWF:Ag, VWF:RCo, FVIII levels, and platelet count
  • Monitor for thrombocytopenia, which can worsen during pregnancy in Type 2B VWD 1, 2

Antenatal Monitoring and Management

• Serial monitoring throughout pregnancy:

  • Check VWF parameters and platelet counts every 4-8 weeks in early pregnancy
  • Increase frequency to every 2-4 weeks in third trimester 1, 2
  • Be alert for paradoxical worsening thrombocytopenia as VWF levels rise during pregnancy

• VWF replacement therapy:

  • Not routinely needed in early pregnancy unless there is significant bleeding
  • Consider initiating VWF concentrate if platelet count drops significantly or bleeding occurs
  • Target trough fibrinogen level of ≥1 g/L throughout pregnancy if replacement needed 3

• Additional monitoring:

  • Serial ultrasound assessments to monitor for placental complications
  • Monitor for signs of placental abruption, which can occur in bleeding disorders 3

Labor and Delivery Planning

• Delivery should be scheduled with availability of:

  • Clinical expertise in hematology and high-risk obstetrics
  • Laboratory support for rapid VWF and platelet monitoring
  • Blood bank support for potential platelet and VWF concentrate needs 3, 1, 2

• VWF replacement therapy during delivery:

  • Administer VWF concentrate to maintain fibrinogen levels ≥1.5 g/L during labor 3
  • Monitor levels throughout delivery (at time of labor and every 12-24 hours)
  • Consider platelet transfusions if significant thrombocytopenia is present 1, 2

• Mode of delivery considerations:

  • Vaginal delivery is possible with proper hematologic support 4
  • Avoid invasive fetal procedures (fetal scalp monitoring, forceps, vacuum-assisted delivery)
  • Consider early recourse to cesarean section if second stage of labor is prolonged 3
  • Consider tranexamic acid (TXA) at the time of delivery for additional hemostatic support 3

Postpartum Management

• Continue close monitoring postpartum:
  • Maintain fibrinogen levels ≥1.5 g/L for at least 3 days after vaginal delivery and 5 days after cesarean section 3
  • Monitor for delayed postpartum hemorrhage, which is a significant risk
  • Consider extended use of tranexamic acid to prevent secondary postpartum hemorrhage 3

Neonatal Considerations

• Prepare for potential neonatal VWD:
  • Collect cord blood at delivery for VWF testing
  • Delay elective invasive procedures until diagnosis is confirmed
  • Establish collaboration between neonatal and pediatric hematology teams 3
  • Be prepared to treat the neonate with VWF concentrate and platelet transfusions if needed, especially if bleeding complications occur 2

Common Pitfalls and Caveats

• Type 2B VWD behaves differently from other VWD subtypes during pregnancy:

  • Unlike Type 1 VWD, Type 2B may not improve during pregnancy
  • Rising VWF levels can paradoxically worsen thrombocytopenia in Type 2B VWD 1, 2
  • Different mutations (e.g., R1306W vs. R1308C) may have different clinical manifestations during pregnancy 1

• Avoid neuraxial anesthesia without adequate factor replacement

• Be vigilant for retained placenta, which can cause significant postpartum bleeding 1

• Remember that VWF parameters can change rapidly during pregnancy in Type 2B VWD, necessitating frequent monitoring 1