Umbilical vein varix (UVV) is a focal dilation of the fetal umbilical vein, often detected during routine prenatal ultrasound.

📌 Introduction

During a routine prenatal ultrasound, you may hear the term

“umbilical vein varix (UVV)”

This can be worrying for many parents.

👉 “Is this dangerous?”

👉 “Will my baby be okay?”

Let’s break it down in simple terms.

📌 1. Key Point First

👉 Most cases have a good outcome

👉 But regular follow-up is essential

📌 2. What is Umbilical Vein Varix?

The umbilical vein carries oxygen and nutrients from the placenta to the fetus.

👉 When a portion of this vein becomes focally dilated,

it is called Umbilical Vein Varix (UVV).

📌 3. How Does It Look on Ultrasound?

• A round or oval anechoic structure in the fetal abdomen
• Color Doppler confirms blood flow
• Usually diagnosed when the diameter is
  👉 ≥ 9 mm

📌 4. Is It Dangerous?

👉 Most cases are benign and result in normal delivery

However, careful monitoring is needed if:

• Abnormal or turbulent blood flow
• Rapid increase in size
• Suspicion of thrombosis

👉 In these cases, closer follow-up is recommended

📌 5. Management

👉 There is no specific treatment

👉 Follow-up ultrasound is the key

• Every 1–2 weeks
• Doppler flow evaluation
• Fetal growth monitoring

📌 6. Important Reminder

👉 In UVV, changes over time are more important

than the initial finding.

📌 Key Takeaway

👉 Umbilical vein varix is a rare finding

👉 But most cases are safe with regular monitoring

Fetal umbilical vein varix with color Doppler flow