354: The prenatal diagnosis of isolated varix of the fetal intra-abdominal umbilical vein (VFIUV): reconsideration of indicated prematurity


      VFIUV was initially reported at stillborns' postmortem. The natural history and management of isolated VFIUV are uncertain; delivery at 34 weeks was suggested to minimize stillborn risk. We aimed to evaluate our experience with isolated VFIUV and its association with perinatal outcome.

      Study Design

      Retrospective case series of all cases of isolated VFIUV (2004-2009) in a tertiary center. VFIUV diagnosis: focal dilatation >9mm or at least 50% larger than the intrahepatic UV, using GA specific criteria. Color-flow performed isolated VFIUV defined: normal antenatal anatomy ultrasound, karyotype and neonate. Timing of delivery was according to treating physician, starting at 35 weeks. Maternal and neonatal records' review; confirmation by phone interviews. Descriptive statistics mean ± SD, range, chi square, Pearson coefficient.


      24 women with fetuses with isolated VFIUV (excluded one lost for follow up). Demographics: maternal age 33 ± 7.1 years; mean gravidity 4.9±2.7; GA initial diagnosis 30.5± 4.4 weeks (20-39); singletons 20 (87%). VFIUV diameter 13 mm ± 2.9 (9-20), turbulent flow 7 (30.4%). All fetuses were live-born, with a normal follow up 2 – 60 months. GA birth 37±2.5 weeks (33-41); birthweight 2866±687.6 grams; males 14 (60.9%). Overall induction 65.2%. Preterm induction due to VFIUV alone performed in 4 (17.4%) ; other causes for preterm delivery 5 (21.7%) (3 twins, 1 PPROM, 1 abruption); allowed to continue until spontaneous labor 14 (60.9%). Overall cesarean 28.6% (4/23). Overall NICU admission 5(21.7%). Timing and mode of delivery were unrelated to the GA diagnosis, size and type of flow of VFIUV (p=0.101, p=0.727, p=0.671 respectively) =0.4. Those induced preterm significantly contributed to the higher rate of cesarean and NICU admission p=0.015 and p= 0.029, respectively.


      Isolated VFIUV is a sonographic diagnosis with an apparent benign course. Our excellent perinatal outcome, unrelated to the structural and flow characteristics of the finding, warrants against early induction and costly preterm births.