Strengths and Limitations-
Prospective nature of the study and simplified subjective approach of AoI waveform analysis rather than objective assessment of waveform were the merits of our study.
This study has limitations like small sample size and prematurity .
Delivery <34WOG had sensitivity (70%) ,Specificity ( 92%) and high positive likelihood ratio of 8.75 for prediction of adverse perinatal outcome, supporting the important role prematurity in the prediction of perinatal outcome .
And also retrograde flow in the aortic isthmus was not used as trigger for delivery .