F60Umbilical vein blood flow in growth restricted fetuses

Abstract

ObjectiveThe present study was designed to determine whether specific umbilical blood flow is reduced in IUGR fetuses.SubjectsThirty‐seven IUGR fetuses of different clinical severity were examined by Doppler ultrasound within four hours of the last nonstress test prior to delivery.MethodAbsolute and weight specific umbilical vein (UV) flow were calculated from measurements of UV diameter and UV mean velocity. UV diameter, velocity and UV flow were calculated also per unit head (HC) or abdominal circumference (AC) and correlated with gestational age.Results UV flow per kilogram was significantly lower in the more severe IUGR fetuses (abnormal umbilical arterial p.i.) than in normal comparable fetuses ( P < 0.001). UV flow per unit head circumference was significantly lower in the three groups ( P < 0.001) than in the control population. The UV diameter/HC was normal whereas UV velocity/HC was significantly lower in IUGR fetuses than in comparable controls. ConclusionsThe present study clearly establishes that umbilical venous blood flow is reduced in IUGR fetuses on a weight specific basis. The sonographic growth parameter which best distinguishes umbilical flow differences of IUGR fetuses from normal fetuses is the head circumference.