Uteroplacental-Cerebral Ratio: A Doppler Parameter for Prognostic Prediction of Late-Onset Fetal Growth Restriction: Single Center Prospective Cohort Study

Purpose: This study aimed to elucidate the accuracy of Doppler parameters in predicting the prognosis of late-onset fetal growth restriction (FGR). Methods: This was a prospective study of 114 pregnancies. Doppler parameters, including the cerebroplacental ratio and pulsatility index (PI) in the middle cerebral, umbilical, uterine artery, were recorded. The new uteroplacental-cerebro ratio (UPCR) was constructed as the ratio of (umbilical artery + mean of the left and right uterine artery) to middle cerebral artery PI. Logistic regression analyses and receiver operating characteristic curves were performed. Results: Adverse outcomes occurred in 37 (32%) neonates. The z values of the middle cerebral artery PI and cerebroplacental ratio were lower (p < 0.001), while the z values of the umbilical artery PI, mean uterine artery PI, and UPCR (p < 0.001) were higher in late-onset FGR in those with compared to those without adverse outcomes. Multivariate logistic regression revealed that only UPCR was independently associated with adverse outcomes (p < 0.001). For predicting the prognosis of late-onset FGR, UPCR showed a fair degree of accuracy (area under the curve [AUC], 0.824). Conclusion: The new UPCR, reflecting the impact of placental impedance from both fetal and maternal sides on fetal well-being, improves the accuracy of prognostic prediction for late-onset FGR.