Mild Umbilical Vein Varix in Pregnancy with Normal Outcome

Introduction

Umbilical vein varix (UVV) is a rare vascular anomaly observed

in approximately 0.4–1.1 per 1,000 pregnancies, most

commonly identified during routine second-trimester anomaly

scans. It is defined as a focal dilatation of the umbilical vein

exceeding 9 mm or 50% greater than the non-dilated segment.

While isolated UVV is often benign, it has been associated with

fetal thrombosis, intrauterine growth restriction (IUGR), fetal

demise, and chromosomal abnormalities in some cases. The

optimal antenatal management remains unclear, particularly

when UVV occurs in isolation without other anomalies. This

case highlights the favourable outcome of a pregnancy

complicated by a mild intra-abdominal UVV.

 

Case Presentation

A 28-year-old primigravida with a BMI of 23 and a background of

tobacco use was referred to fetal medicine after a mid-trimester

anomaly scan at 20 weeks gestation revealed a suspected

umbilical vein varix. The varix was intra-abdominal, measuring

9.3 mm, and situated proximal to the portal vein confluence. The

patient had no prior medical history or family history of

congenital anomalies or genetic syndromes. A comprehensive

fetal anomaly scan by the fetal medicine team confirmed the

diagnosis of UVV with no associated structural or chromosomal

abnormalities.

The patient was thoroughly counselled on potential implications

including risks of thrombosis, fetal distress, and stillbirth. Non-

invasive prenatal testing (NIPT) was offered but declined.Serial

growth scans were arranged every 4 weeks, and fetal growth 

consistently measured between the 50th and 90th centiles.

There were no signs of abnormal Dopplers or oligohydramnios. Umbilical

vein Doppler flow remained normal with no evidence of thrombosis.

At 39+1 weeks, the patient presented with spontaneous rupture of

membranes. She was admitted and labour was augmented due to lack of

progress. She proceeded to have an uncomplicated spontaneous vaginal

delivery. A healthy male infant weighing 3.48 kg was delivered, with Apgar

scores of 9 and 10 at 1 and 5 minutes respectively. The neonate was

reviewed by the paediatric team and discharged with no concerns. The

umbilical cord was examined postnatally, and the varix was confirmed

histologically.

 

Discussion 

Umbilical vein varices can be classified as intra-abdominal or extra-abdominal,

with the former being more commonly reported and often detected incidentally.

The pathogenesis is believed to involve focal weakness in the vessel wall, which

may predispose to stasis and thrombosis. However, the clinical relevance largely

depends on size, location, and the presence of co-existing anomalies.

In this case, the UVV was isolated and measured just above the diagnostic

threshold. No signs of thrombosis or circulatory compromise were observed, and

fetal growth remained appropriate. The case aligns with findings from similar case

reports suggesting that isolated mild UVV may carry a good prognosis when

properly monitored.

Management typically includes frequent fetal growth and Doppler assessments to

detect early signs of fetal compromise. There is no consensus on the ideal

delivery timing in isolated UVV; however, most authors recommend delivery at

term in the absence of complications. Our approach mirrored this guidance, with

serial ultrasounds and careful intrapartum planning.

This case reinforces the importance of shared decision-making and

multidisciplinary input. Fetal medicine specialists, obstetricians, and

neonatologists collaborated to ensure a coordinated plan from diagnosis to

delivery, contributing to the positive maternal and neonatal outcome.

 

Conclusion 

solated intra-abdominal umbilical vein varix, particularly when mild and

without coexisting abnormalities, may not significantly impact

pregnancy outcomes. With close antenatal monitoring and timely

delivery, good perinatal outcomes are achievable. This case supports a

conservative approach in selected low-risk patients, emphasizing the

role of structured surveillance and individualized care.

 

Reference 

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