Can patients with velamentous cord insertion deliver vaginally?

Vaginal Delivery with Velamentous Cord Insertion

Patients with velamentous cord insertion should undergo elective cesarean delivery between 34-36 weeks to prevent potentially fatal fetal hemorrhage, particularly when vasa previa is present.

Understanding Velamentous Cord Insertion

Velamentous cord insertion (VCI) is an abnormal placental cord insertion where umbilical vessels diverge and traverse between the amnion and chorion before reaching the placenta, leaving vessels unprotected and exposed to pressure and injury during pregnancy and labor.

Risk Factors for VCI

• Multifetal gestation (OR = 9.2) 1
• Infertility treatments (OR = 4.3) 1
• Chronic hypertension (OR = 2.2) 1
• More common in twin pregnancies (1.6-40% vs 0.4-11% in singletons) 2

Management Recommendations

Prenatal Diagnosis

• Systematic assessment of placental cord insertion should be performed during routine second-trimester ultrasound 3
• Color Doppler ultrasound can identify VCI with high specificity 2
• Early detection is essential as this condition represents an obstetric emergency 4

Delivery Planning

When VCI is Associated with Vasa Previa:

• Elective cesarean section is strongly recommended 5
• Timing: Between 34-36 weeks of pregnancy, before onset of labor 5
• Corticosteroid treatment for fetal lung maturation at 32 weeks due to increased risk of preterm delivery 5

When VCI is Present Without Vasa Previa:

• Cesarean delivery is generally recommended due to:
  • Significantly increased risk of cesarean delivery (OR = 3.3) 1
  • Higher risk of placental abruption (OR = 8.2) 1
  • Increased risk of perinatal mortality (OR = 4.07) 1
  • Risk of fetal hemorrhage if vessels rupture during labor 5

Complications Associated with VCI

VCI is associated with multiple adverse pregnancy outcomes:

• Intrauterine growth restriction (OR = 4.3) 1
• Polyhydramnios (OR = 2.3) 1
• Fetal malformations (OR = 2.2) 1
• Preterm birth (OR = 4.6) 1
• Low Apgar scores (OR = 2.3) 1

Clinical Pearls and Pitfalls

Important Considerations

• VCI may be an obscure cause of emergency cesarean section in otherwise low-risk pregnancies 3
• Approximately 2% of low-risk pregnant women require emergency cesarean section after onset of labor, with half potentially associated with placental and umbilical cord abnormalities 3
• Spontaneous rupture of membranes in cases with vasa previa carries a major risk of fetal hemorrhage, which is often lethal 5

Monitoring Recommendations

• Close monitoring of pregnancies with risk factors for VCI 1
• Regular assessment of fetal growth and well-being
• Preparation for potential emergency delivery if diagnosed late in pregnancy

Conclusion

The evidence strongly indicates that patients with velamentous cord insertion, particularly when associated with vasa previa, should undergo planned cesarean delivery to prevent potentially catastrophic fetal hemorrhage. The timing of delivery should be carefully planned, with consideration for administering corticosteroids for fetal lung maturity if early delivery is anticipated.