Background: A high uterine artery pulsatility index (PI) reflects a defective development of placental bed spiral arteries. This study assesses early uterine and spiral arteries Doppler and their relation to adverse pregnancy events.
Methods: A retrospective cohort study was conducted on 291 pregnant women between 6 and 10+ weeks' gestation, where uterine and spiral arteries were assessed by transvaginal Doppler ultrasound at 6-10+ and 11-13+ weeks' gestation. All participants were followed up regarding the risk for miscarriage, PIH, and the need for neonatal ICU admission.
Results: Normal reference ranges were obtained for mean uterine PI and spiral resistance index (RI) during 6-10+ weeks' gestation. There was a significantly increased risk of miscarriage in women with higher uterine PI (p=0.042). Besides, there was a moderate positive correlation (r=0.61) between mean uterine PI and spiral RI during the first scan (6 - 10+ weeks). Also, there was a fair, positive correlation (r=0.33) between the mean uterine PI during the first and the second ultrasound scans.
Conclusion: Early measurement of uterine and spiral arteries Doppler may benefit as an early tool for detecting those at risk of miscarriage.