Sonographic umbilical vessel morphometry and perinatal outcome of fetuses with a lean umbilical cord.

Purpose: This study was undertaken to assess whether changes in umbilical cord vessel morphometry are associated with an increased risk of adverse perinatal outcome among fetuses with a lean umbilical cord on sonography.

Patients And Methods: A total of 160 fetuses with a sonographically lean umbilical cord (cross-sectional area below the 10th percentile for gestational age) after 20 weeks of gestation were enrolled. The cross-sectional areas of the umbilical cord and its vessels were measured. Outcome variables investigated were perinatal death, admission to the neonatal intensive care unit, intrauterine growth restriction, and 5-minute Apgar score.

Results: The proportions of perinatal death (1/96 versus 6/64, p < 0.05) and admission to the neonatal intensive care unit (17/96 versus 22/64, p < 0.05) was significantly higher among fetuses with an umbilical vein area below or equal to the 10th percentile for gestational age than among those with an umbilical vein area greater than the 10th percentile. No differences were found in the proportions of perinatal death, neonatal intensive care unit admission, 5-minute Apgar score < 7, and intrauterine growth restriction when fetuses with umbilical vein areas below or equal to the 10th, the 5th, and the 2.5th percentiles for gestational age were compared. No difference was found in the umbilical artery area and Wharton's jelly area among the groups.

Conclusion: Among fetuses with a sonographically lean umbilical cord, a significant relationship exists between an umbilical vein area below or equal to the 10th percentile and an adverse neonatal outcome.