Transverse umbilical arterial diameter: technique for the prenatal diagnosis of single umbilical artery.
We investigated the relationship between the transverse umbilical arterial diameter and the presence of a single umbilical artery. Further, we speculated that fetal physiologic and hemodynamic limitations in pregnancies complicated by a single umbilical artery would result in larger umbilical arterial diameters than the typical three-vessel cord. The identification of a sufficiently large umbilical artery may be pathognomonic for single umbilical artery. The transverse umbilical arterial diameter was obtained in 100 consecutive, uncomplicated singleton pregnancies between 20 and 38 weeks' gestation. These measurements were compared with the transverse umbilical arterial diameter of 23 pregnancies in which a single umbilical artery was identified with ultrasonography and postnatal examination. Transverse umbilical arterial diameter measurements of the two groups were compared. Before 36 weeks' gestation, all pregnancies with a single umbilical artery had a transverse umbilical arterial diameter measurement > 4 mm and all pregnancies with two umbilical arteries had a transverse umbilical arterial diameter measurement < or = 4 mm. Because oligohydramnios, multiple pregnancy, or suboptimal cord position may obscure the expeditious identification of the number of umbilical cord vessels, measurement of the transverse umbilical arterial diameter may prove useful in the identification of single umbilical artery. On the basis of this preliminary evaluation, we suggest that a transverse umbilical arterial diameter measurement > 4 mm is predictive of single umbilical artery between 20 and 36 weeks' gestation.
Persutte
W H
WH
Department of Obstetrics and Gynecology, University of Colorado Health Sciences Center, Denver 80262.
Lenke
R R
RR
D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D005865:Gestational Age; D006801:Humans; D011237:Predictive Value of Tests; D011247:Pregnancy; D011248:Pregnancy Complications; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal; D014469:Umbilical Arteries / Q000002:abnormalities / Q000000981:diagnostic imaging* / Q000473:pathology*; D014470:Umbilical Cord