Doppler changes in the vertebral, middle cerebral, and umbilical arteries in fetuses delivered after 34 weeks: relationship to severity of growth restriction.

OBJECTIVE

To determine the association between Doppler changes in the fetal vertebral (VA), middle cerebral (MCA), and umbilical arteries (UA) and severity of growth restriction (FGR) in fetuses delivered after 34 weeks.

METHOD

Five hundred seventy-one Doppler examinations of the VA, MCA, and UA were performed between 26 and 41 weeks of gestation. Values were converted into multiples of the median and divided into birth weight (BW) categories: BW>P10(th) , BW<P10(th) , BW<P5 th, and BW<P3(rd) . Differences were evaluated and multivariate logistic regression models plus receiver-operating characteristic curves were calculated to determine the accuracy of Doppler measurements for the prediction of FGR percentiles.

RESULTS

The UA pulsatility index (PI) was significant predicting BW<P10(th) and BW<P3(rd) , the VA PI was significant predicting BW<P5(th) and BW<P3(rd) . Finally, the MCA PI was not predictive of any degree of severity of FGR. In addition, only VA and UA differences were statistically significant.

CONCLUSION

In fetuses delivered after 34 weeks, mild degrees of growth restriction are better associated with high UA PI whereas severe degrees are associated with low VA PI but not with low MCA PI.