Prediction of small-for-gestational age infents by quantitative assessment of diastolic notch in uterine artery flow velocity waveforms

ABSTRACT

To assess the performance and clinical usefulness of the notch depth index [NDI] in predicting small-for-gestational age infants [SGA] in comparison to the previously defined abnormalities in uterine blood flow velocity waveforms; peak systolic over protodiastolic velocities [A/C] ratio. Presence of protodiastolic notch and resistance index [RI]. This prospective clinical study included evaluation of pulsed Doppler abnormalities uterine artery velocity waveforms in 673 nulliparae with normal singleton pregnancies at 16-18 weeks and at 26 weeks gestation. Main outcome measures: Delivery of small for gestational age [SGA] infants. SGA developed in 11% of nulliparae. Although early Doppler screening was associated with high false positive results, yet two-stage screening avoided false negative cases. NDI was found to be a better predictor than other Doppler indices [A/C ratio, protodiastolic notch and RI]. NDI improved, both sensitivity and PPV as determined by other Doppler indices. NDI measurements were clinically useful in predicting for gestational age infant than other conventional Doppler indices