Uterine artery Doppler velocimetry in pregnant women with lateral placentas

The aim of this study was to compare the efficacy of placental, non-placental, mean of both uterine arteries Doppler velocimetry at 22-24 weeks gestation in the prediction of pregnancy induced hypertension (PIH) and intrauterine growth retardation (IUGR). Flow velocity waveforms were obtained by means of color and pulsed Doppler in 481 patients with lateral placentas at 22-24 weeks gestation. Placental location was determined by real time ultrasonography. Comparisons were performed between controls and pregnancies complicated by PIH and IUGR. Sensitivities, false positive rates and positive predictive values for PIH and IUGR of resistance indices (RI) above the 90(th) percentile, and diastolic notches in placental, non-placental or both uterine arteries were calculated. A mean uterine artery RI greater than or equal to 0.66 (90(th) centile) had better sensitivity than the placental (26.8% vs 17.1% for IUGR and 41.7% vs 33.3% for PIH) and the non-placental uterine artery (26.8% vs 21.9% for IUGR and 41.7% vs 33.3% for PIH). The presence of a diastolic notch in the placental uterine artery increased sensitivity (31.7% for IUGR and 50.0% for PTH) and positive predictive value of the test. In patients with laterally implanted placentas a mean of both uterine arteries RI above the 90(th) centile and the presence of a diastolic notch in the placental uterine artery at 22-24 weeks have a higher predictive value for the subsequent development of PIH and IUGR than the separate evaluation of the 2 uterine arteries.