Persistent right umbilical vein: incidence and significance.
OBJECTIVE
To conduct a prospective evaluation of the incidence and neonatal outcome of fetuses with persistent right umbilical vein. This condition had traditionally been considered to be extremely rare and to be associated with a very poor neonatal prognosis, but later evidence has raised some doubts about the veracity of these contentions.


METHODS
Between August 1995 and November 1998, 8950 low-risk patients were prospectively evaluated at two medical centers. The sonographic diagnosis of a persistent right umbilical vein was made in a transverse section of the fetal abdomen when the portal vein was curved toward the stomach, and the fetal gall bladder was located medially to the umbilical vein.


RESULTS
Persistent right umbilical vein was detected in 17 fetuses during the study. Four of them had additional malformations, of which three had been detected antenatally.


CONCLUSIONS
We established that the incidence of persistent right umbilical vein in a low-risk population is 1 : 526. We believe that the sonographic finding of this anomaly is an indication for conducting targeted fetal sonography and echocardiography. When the persistent right umbilical vein is connected to the portal system and other anomalies are ruled out, the prognosis can generally be expected to be favorable.
Wolman
I
I
The Ultrasound Unit, Department of Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center and The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Gull
I
I
Fait
G
G
Amster
R
R
Kupferminc
M J
MJ
Lessing
J B
JB
Jaffa
A J
AJ
D000013:Congenital Abnormalities / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D015994:Incidence; D011247:Pregnancy; D011256:Pregnancy Outcome; D011379:Prognosis; D011446:Prospective Studies; D016216:Ultrasonography, Prenatal; D014471:Umbilical Veins / Q000002:abnormalities* / Q000000981:diagnostic imaging