SINGLE UMBILICAL ARTERY AND MULTIPLE GESTATIONS

• 5-11% of cases of SUA occur in multiple pregnancy (1).
• Multiple gestations have a 3-7 fold increased risk of SUA (1).
• Occurs in 2% of twin infants and 4% of twin deliveries (1).
• Twin infants with SUA have no greater risk of congenital malformations than singletons with SUA (1).
• Twin fetuses discordant for SUA:
• The smaller twin had the SUA in 82% of cases (1).

REFERENCES

1. Heifitz SA. Single umbilical artery: a statistical analysis of 237 autopsy cases and review of the literature. Perspect Pediatr Pathol 1984;8:345-378.