Isolated fetal umbilical vein varix--prenatal sonographic diagnosis and suggested management

To present our experience with fetuses with umbilical vein varix (UVV), to investigate possible risk factors and to suggest a management scheme of evaluation.

A study of 14 pregnancies complicated with isolated UVV was performed. Data collected included sonographic characteristics of the UVV, pregnancy outcome including induction of labour, mode of delivery, birthweight, and neonatal complications.

UVV was diagnosed at a median gestational age of 27.5 weeks' gestation (range: 22-34 weeks). The average diameter of the UVV at diagnosis was 10.6 mm (range: 8-15 mm), and the maximal diameter during follow-up was 12.8 mm (range: 10-18 mm). The median gestational age at delivery was 36.1 weeks (range: 34-40 weeks), with an average birthweight of 2834 g (range: 1725-3715 g). Five women underwent emergent cesarean section. In fetuses with turbulent flow in the UVV there was a tendency to larger maximal sizes of the UVV, earlier gestational age at delivery and smaller birthweight. There were no cases of fetal or neonatal demise.

We suggest that fetuses with UVV should be followed weekly from diagnosis to 28 weeks, and twice a week afterwards. Induction of labour should be considered at 36-37 weeks' gestation or at signs of fetal distress.