ABSTRACT
In 139 pregnancies in which intrauterine growth retardation (IUGR) was suspected at
routine ultrasound screening at 32 weeks of gestation, blood velocity in the fetal
aorta and umbilical artery was recorded by a pulsed Doppler ultrasound every second
week until delivery. The maximum blood flow velocity waveforms (FVWs) were analyzed
for pulsatility index (PI) and blood flow class (BFC). In both vessels, an abnormal
PI (> mean + 2 SD of the normal population) and abnormal BFC at the final antenatal
examination were significantly associated with the occurrence of IUGR (birthweight
≤ mean - 2 SD) (p < 0.001), operative delivery for fetal distress (p < 0.001), and
a low 1-minute Apgar score (≤ 7). PI in the umbilical artery was a better predictor
of fetal outcome than was the aortic PI, but the BFC was similarly predictive of fetal
outcome in both vessels. The data indicate that a simple umbi lical artery examination,
which can be preformed blindly with the Doppler ultrasound instrument without the
help of a real-time scanner, is a reliable method for monitoring fetal status in pregnancies
when IUGR is suspected.
