Prenatal diagnosis of fetal intra-abdominal umbilical vein varix: report of 2 cases

Isolated fetal umbilical vein varix and the association with intrauterine fetal death and fetal growth restriction: A systematic review, meta-analysis, and nested retrospective cohort study

OBJECTIVES

To assess the risk of intrauterine fetal death (IUFD) and fetal growth restriction (FGR) in fetuses with an isolated fetal intra-abdominal umbilical vein varix (i-FIUVV).

METHODS

A retrospective cohort study combined with a systematic review and meta-analysis of the literature was performed. In the retrospective cohort study, all singleton fetuses with an i-FIUVV in the fetal medicine units of the Amsterdam UMC (between 2007 and 2023) were analyzed. The primary outcome measures were IUFD and FGR. The sample proportions of IUFD and FGR were depicted as risk percentages. The IUFD proportion was compared to the regional reference population and the FGR proportion was compared to the reported proportions in Europe. The secondary outcome measures were gestational age at diagnosis, initial and maximal FIUVV diameter, fetal monitoring in pregnancy, turbulent flow in the varix, thrombus formation in the varix, induction of labor, gestational age at birth, and birthweight centile. The proportion of fetuses with a birthweight below the 10th centile was compared with that of the regional reference population. The systematic review included all cases from eligible literature published between 2007 and 2023 supplemented by the data of our retrospective cohort study. In the systematic review and meta-analysis, the pooled proportions of IUFD and FGR were assessed in fetuses with i-FIUVV.

RESULTS

The retrospective cohort included 43 singletons with an i-FIUVV. The IUFD risk was 0% [Confidence Interval, CI: 0%-8.2%], which did not differ significantly from 0.3% in the reference population, p = 1.0. The risk of FGR was 16.3% [CI: 6.8%-30.7%] in the studied population, which is higher than the reported incidence of FGR in Europe ranging from 5%-10%. The proportion of fetuses with birthweights below the 10th centile was higher in our cohort compared with the reference population (23.3 vs. 9.9%, p < 0.01). The systematic review included 12 articles, three abstracts, and our current cohort. In total, 513 cases with an i-FIUVV were included. The pooled risk was 0.4% [CI: 0.1%-1.7%] for IUFD and 5.2% [CI: 1.1%-21.3%] for FGR. The mean gestational age at birth did not exceed 39 weeks in neither the cohort (38.7 weeks) nor the pooled literature (37.6 weeks).

CONCLUSION

An i-FIUVV in singletons is not associated with an increased IUFD risk up to 39 weeks of gestation but is possibly associated with FGR. The incidence of FGR in our cohort was higher than in the pooled literature (16.3% vs. 5%) but FGR definitions in the included studies varied. The proportion of birthweights below the 10th percentile in our cohort was significantly higher than in the reference group. Thus, based on these findings, we suggest conducting sonographic growth assessments while simultaneously assessing the i-FIUVV. No further monitoring and follow-up are indicated up to 39 weeks of gestation. After 39 weeks of gestation, data on fetuses with i-FIUVV and their outcomes are lacking.

Partial molar pregnancy with a normal live fetus and umbilical cord abnormalities: A novel association with long-term follow-up: A case report

A euploid fetus in a partial molar pregnancy can develop umbilical cord abnormalities as pregnancy goes on. So, careful examination of the umbilical cord can determine fetuses at risk for ominous adverse effects.

Fetal Intra-abdominal Umbilical Vein Aneurysm

Importance

Fetal umbilical vein aneurysm is an uncommon anomaly that accounts for approximately 4% of umbilical cord abnormalities. The rate of intrauterine fetal death is reported to be approximately 4% to 5%, higher than the background rate of 0.7% that is generally reported during pregnancy.

Objective

The aim of this study was to review the pathophysiology, diagnosis, and clinical management of fetal umbilical vein aneurysm.

Evidence Acquisition

Advances in high-resolution ultrasound combined with color Doppler and 3-dimensional rendering have contributed to an increased understanding of the fetal venous circulation in recent years.

Results

When the diagnosis of umbilical vein aneurysm is made, the patient should undergo a detailed ultrasound evaluation of the fetal anatomy, including fetal echocardiography, to exclude associated anomalies. Amniocentesis should be offered when other anomalies are found. Patients should be informed about the potential for an unfavorable outcome of pregnancy and should undergo close ultrasound surveillance to assess the size of the aneurysm, as well as any evidence of thrombosis or signs of hydrops.

Conclusions

The main prognostic feature associated with a poor outcome of umbilical vein aneurysm seems to be the presence of other anomalies. Early diagnosis is associated with a somewhat worse prognosis, and most fetal deaths have been observed between 27 and 30 weeks of gestation. In the third trimester, it is reasonable to perform serial ultrasound examinations to assess fetal growth, the size of the aneurysm, and the blood flow pattern within the aneurysm.

The Triple Test Markers Profile Among Fetuses and Children Diagnosed With Umbilical Vein Varix

Umbilical vein varix (UVV) is defined as a focal enlargement of the umbilical vein and represents approximately 4% of fetal umbilical cord malformations. The reported neonatal outcome of fetuses with UVV varies widely due to its rarity, hence the small sample sizes of the case series in the literature. Earlier studies reported high fetal mortality, but more recent reports have demonstrated no association between UVV and intrauterine fetal death. A recent study has described a possible association between UVV diagnosed prenatally and child developmental delay. The present study of fetuses with UVV was done to evaluate and compare the levels of triple test serum biomarkers used for Down syndrome screening (human chorionic gonadotropin, α-fetoprotein, and unconjugated estriol) between a group of fetuses with uneventful obstetric outcome versus a subgroup of children with developmental delay.

The prenatal diagnosis of isolated fetal varix of the intra-abdominal umbilical vein is associated with favorable neonatal outcome at term: a case series

OBJECTIVE

Varix of the fetal intra-abdominal umbilical vein (VFIUV) has been reported to be associated with an increased risk of adverse perinatal outcome and especially with intra-uterine fetal demise (IUFD). Induction of preterm birth, as early as 32-34 weeks gestation has been suggested to minimize this risk. We aimed to evaluate our center experience with the antenatal diagnosis of VFIUV and review the relevant literature.

METHODS

This is a retrospective case series of all cases (between 2004 and 2009) where the sonographic antenatal diagnosis of VFIUV was registered at any gestational age (GA). Ultrasound, maternal and newborn electronic medical records were used. Descriptive statistics were employed as appropriated and correlation coefficient (r) calculated.

RESULTS

We identified 24 women with fetuses, with isolated VFIUV (excluding one lost-to-follow-up). GA at diagnosis was 30.5 ± 4.4 weeks; 13 (56.5 %) cases were diagnosed <32 weeks. The mean VFIUV diameter was 13 ± 2.9 (range 9-20) mm and turbulent flow was reported in 7 cases (30.4 %). GA at birth was 37 ± 2.5 weeks. The small for gestational age rate was 4 % (1/23), while no case of IUFD occurred. The group induction of labor rate was 65.2 %, while 43 % (10/23) due to the diagnosis of VFIUV alone: 17 % (4/23) preterm and 26 % (6/23) at term. The cesarean rate was 17 % (4/23) and NICU admission was required for five neonates (21.7 %). The preterm induction of birth was related to a significantly increased risk for cesarean and neonatal morbidity (p = 0.015; p = 0.029, respectively). The mode of delivery was not associated with the GA at diagnosis, size/type of flow of VFIUV (r = 0.101; r = 0.727; r = 0.671, respectively) overall (r) = 0.4. All fetuses were live-born with normal follow-up at 2-60 months.

CONCLUSION

Isolated VFIUV has a favorable perinatal outcome at term, unrelated to the structural and flow characteristics of VFIUV. We show that follow-up for growth abnormalities with no preterm induction of birth is a safe maternal and neonatal approach.

Isolated fetal intra-abdominal umbilical vein varix: clinical importance and recommendations

This series describes a single center's experience in follow-up and management of fetuses with an isolated fetal intra-abdominal umbilical vein varix. All cases with a fetal intra-abdominal umbilical vein varix that were diagnosed or referred to our medical center over 15 years were followed and managed. The definition of a fetal intra-abdominal umbilical vein varix used was a segment dilated to 9 mm or greater or at least 50% wider than the diameter of the adjacent umbilical vein. Over the 15-year period, our center had approximately 65,000 births with 28 cases of isolated fetal intra-abdominal umbilical vein varices: a prevalence rate of 1 case per 2300 births. Three of the 28 cases (10.7%) had intrauterine growth restriction. Five of 30 fetuses (17%) showed turbulent flow in the varix. We had no cases of intrauterine fetal death, and 27 of the 28 neonates had good outcomes. In contrary to earlier reports, we found that when a fetal intra-abdominal umbilical vein varix is isolated, a good fetal outcome is expected. On the basis of our experience, we have changed our policy and do not recommend inducing preterm labor. Nevertheless, close fetal surveillance until delivery is warranted.