Cerebroplacental Ratio on Doppler as a Predictor of Fetuses at Risk of Perinatal Complications

Background: Doppler velocimetry is the best method of surveillance for fetal hypoxemia during pregnancy. Cerebroplacental ratio (CPR), has been suggested as a useful clinical simplification. It is believed that the CPR better predicts adverse perinatal outcomes than its individual components and better than conventional anthropometric models. Therefore, the aim of this study is to evaluate the significance of the cerebroplacental 10th centile threshold measured weekly from 36 weeks of gestation till delivery as a screening test for prediction of need for Cesarean section for intrapartum fetal compromise and the adverse neonatal outcome in women with normally grown fetuses and uncomplicated pregnancy.

Methods: This study was carried out on 40 pregnant women uncomplicated, singleton pregnancy with appropriately grown fetuses on clinical assessment. The last Doppler indices including cerebroplacental ratio measurement obtained before labor was reported. CPR values below 1.1 were reported as abnormal. Various studies have variably defined the threshold of abnormal CPR ratio as <1.08.

Results: There was significant decrease in the Mean of CPR among patients who had anemia compared to those without anemia. In addition, there was no significant association seen between low CPR and having previous history of abortion or IUGR as well as being a smoker. There was no significant difference between cases who had normal and abnormal CPR regarding gestational age at delivery. There was no difference between cases who had normal and abnormal cerebroplacental ratio regarding mode of delivery. there was significant decrease in the prevalence of low birth weight among group who had CPR≥1.08. CPR <1.08 was significantly associated with neonatal complication like NICU admission, and neonatal death. There was no statistically significant relationship between cerebroplacental ratio and neonatal complication like IUFD, and neonatal sepsis. There was no statistically significant association between the mean cerebroplacental ratio and IUFD. There was statistically significant association between the mean cerebroplacental ratio and NICU. There was no statistically significant association between the mean cerebroplacental ratio and neonatal sepsis. The mean cerebroplacental ratio of 0.93± 0.22 has a significant association with neonatal death.

Conclusion: A low cerebroplacental ratio reflects redistribution of the cardiac output to the cerebral circulation and has been shown to improve accuracy in predicting adverse outcome compared with Middle cerebral artery (MCA) or Umbilical artery (UA) Doppler alone. Therefore, integrating CPR in clinical management may help to better identify fetuses at risk for adverse perinatal events, since abnormal CPR has been associated with an increased risk of perinatal complications.