A longitudinal evaluation of the efficacy of umbilical Doppler velocimetry in the diagnosis of intrauterine growth retardation.

In a prospective study of 149 patients, the interrelationship among abnormal umbilical artery systolic/diastolic (S/D) ratios, maternal hypertension and IUGR was examined. Abnormal S/D ratio was defined as a value greater than or equal to 3 in the third trimester. Results suggest that the incidence of abnormal S/D ratios are significantly higher in hypertensive as compared to normotensive pregnancies, as well as in small for gestational age (SGA) compared to appropriate for gestational age (AGA) deliveries. Although umbilical artery velocimetry was more predictive of IUGR in hypertensive than normotensive pregnancies, overall 45% of SGA births were not identified by this technique. Further classification of potential etiologies and mechanisms of IUGR based on maternal factors should improve the positive predictive value of the abnormal S/D ratio in subgroups of pregnant women. In the interim the results strongly suggest that abnormal S/D ratio in a hypertensive pregnancy should alert the obstetrician to the probability of IUGR.