Correlation Between Fetal Middle Cerebral Artery and Umbilical Artery Doppler Ratio at 38-40 weeks of Gestation with Fetal Distress and Adverse Perinatal Outcome

Abstract

Background and Objectives: The study aimed to determine the correlation between fetal middle cerebral artery and umbilical artery doppler ratio with fetal distress at 38-40weeks of gestation. Materials and Methods: In this prospective observational study, 100 pregnant patients between 38-40 weeks of gestational age with no complications were selected from April 2020 to October 2021.They were subjected to Doppler ultrasonography and all the indices such as Middle cerebral artery, Umbilical artery, and Cerebroplacental (C/U) ratio were noted. The patients were followed till delivery and monitored for maternal, fetal, and neonatal outcomes. Results: The mean cerebroplacental ratio was 1.33. there was a significant association between the low C/U ratio with caesarean section and poor perinatal outcome in terms of APGAR <7 at 5minutes, meconium liquor, respiratory distress syndrome, neonatal death, and NICU admission. There was a significant association of low middle cerebral artery PI (p=0.0004), high umbilical artery PI (P=<0.0001), and low C/U ratio (p=<0.0001) with fetal distress. The C/U ratio cut-off ≤1.33 led to sensitivity, specificity, PPV, and NPV of 82.86, 78.46, 67.4, and 89.5%, respectively. There was a linear relationship between birth weight (p=0.10) and postdelivery cord pH(<0.0001) with a C/U ratio. Hence, although sensitivity of cerebroplacental ratio and umbilical artery PI are comparable, the specificity of cerebro-placental ratio is higher than that of umbilical artery PI. Conclusion: It may be concluded that the Cerebroplacental ratio is a better predictor of fetal distress and adverse perinatal outcome than the individual pulsatility index of middle cerebral artery and umbilical artery taken alone.