Value of Third Trimester Uterine Artery Doppler in High-risk Pregnancies for Prediction of Adverse Perinatal Outcome

Objective: To determine the usefulness of uterine artery Doppler in evaluation of third trimester high-risk pregnancies in prediction of adverse perinatal outcome. Methods: In this prospective study uterine artery Doppler parameters such as PI and early diastolic notch were recorded in a group of 60 high-risk pregnancies mainly consisting of pre-eclampsia and small for gestational age. Uterine artery score (UAS) was calculated from the Doppler parameters and a score > 2 was considered abnormal. Perinatal outcome was then correlated to this score and compared with umbilical artery Doppler. Results: Abnormal UAS was noted in 72% of the study group while umbilical artery Doppler was abnormal in only 35%. All the five perinatal deaths and high-rate of perinatal morbidity was observed when both uterine and umbilical artery Dopplers were abnormal. Perinatal morbidity parameters such as birth weight < 2 kg, gestational age < 34 weeks and NICU admission was significantly high in 23 women who had abnormal UAS with normal umbilical artery Doppler. In pregnancies beyond 34 weeks abnormal uterine artery Doppler was a better predictor of adverse outcome than umbilical artery Doppler. Conclusion: Abnormal uterine artery Doppler is a reliable predictor of adverse perinatal outcome in high-risk pregnancies with preeclampsia and fetal growth restriction. Normal uterine artery Doppler in third trimester is reassuring. Thus inclusion of uterine artery Doppler along with umbilical artery Doppler in high-risk pregnancy in third trimester will improve fetal surveillance.