What is the recommended management for a pregnancy with velamentous (umbilical cord) insertion?

Management of Velamentous Umbilical Cord Insertion in Pregnancy

Patients with velamentous umbilical cord insertion can safely deliver vaginally as long as vasa previa has been ruled out and other obstetric indications for cesarean delivery are not present. 1

Diagnosis and Surveillance

• Prenatal diagnosis using ultrasound with color Doppler is essential for identifying velamentous cord insertion

  • Color Doppler significantly improves detection compared to gray-scale ultrasound alone 1
  • The placental cord insertion site can be identified in 99% of cases using this approach 2

• Initial surveillance recommendations:

  • Begin increased ultrasound surveillance at 16 weeks gestation 1
  • Schedule ultrasounds every 2-3 weeks to monitor for:
    • Fetal growth restriction
    • Amniotic fluid abnormalities
    • Doppler abnormalities 1
  • For monochorionic twins, consider weekly surveillance if velamentous insertion is identified 1

Critical Assessment for Vasa Previa

• The most important step in management is ruling out vasa previa, which is a contraindication to vaginal delivery 1
• Vasa previa assessment requires:
  • Transabdominal ultrasound with color Doppler
  • Transvaginal ultrasound with color Doppler for confirmation 1
  • Special attention when velamentous insertion is identified, as there is a higher risk of associated vasa previa 3

Management Based on Pregnancy Type

Singleton Pregnancies

• Routine monitoring for:
  • Intrauterine growth restriction (4.3 times higher risk) 4
  • Preterm birth (4.6 times higher risk) 4
  • Placental abruption (8.2 times higher risk) 4
  • Polyhydramnios (2.3 times higher risk) 4

Multiple Gestations

• More intensive monitoring required as velamentous insertion is more common (up to 22% in monochorionic twins vs 1% in singletons) 1
• Document cord insertion location for each fetus to determine chorionicity 1
• Consider earlier delivery in monochorionic twins with velamentous insertion due to increased complications 1
• Fetal echocardiography is recommended, especially in monochorionic twins, due to increased risk of cardiac anomalies 1

Delivery Planning

Vaginal Delivery

• Appropriate when:
  • Vasa previa has been definitively ruled out
  • No other obstetric indications for cesarean exist 1
• Requires continuous fetal monitoring during labor
• Avoid artificial rupture of membranes when possible 1

Cesarean Delivery

• Indicated when:
  • Vasa previa is present
  • Other obstetric indications exist
  • Signs of fetal distress occur during labor 1, 5

Common Pitfalls and Caveats

1. Failure to diagnose: Systematic assessment of cord insertion should be part of routine obstetric ultrasound to avoid missing this condition 1

2. Inadequate imaging: Posterior placenta in the third trimester may limit visualization; ensure comprehensive evaluation earlier in pregnancy 2

3. Overlooking vasa previa: This is the most dangerous complication and must be ruled out before allowing vaginal delivery 1

4. Underestimating risks in multiple gestations: Velamentous insertion increases the risk of twin-twin transfusion syndrome to 27% (vs 7% with normal insertions) 1

5. Insufficient monitoring: Current standard antepartum methods may not be fully effective in detecting all complications of abnormal insertion 6

By following this structured approach to diagnosis and management, the risks associated with velamentous cord insertion can be significantly reduced, allowing for appropriate delivery planning and improved outcomes.