Cerebroplacental Ratio: Can It Be Taken as a Single Predictor of Adverse Perinatal Outcome in Singleton Uncomplicated Pregnancy at Term

Abstract

Introduction: The brain-sparing (BS) phenomenon is considered an adaptive mechanism of the fetus, which is activated to protect the fetal brain in adverse conditions. The current challenge is, therefore, to identify vulnerable fetuses at risk of hypoxic complications, particularly within an apparently low-risk cohort before the onset of labor. The cerebroplacental ratio (CPR) is emerging as an important predictor of adverse pregnancy outcomes, and this has implications for assessment of the well-being of SGA and AGA fetuses close to term. Materials and methods: It was a hospital-based prospective observational study. After obtaining informed consent from the patient, she was subjected to detailed history-taking and examination and underwent antenatal USG with color Doppler for CPR calculation. Observations and results: The mean age of females enrolled in the study was 25.95 ± 3.50 years. About 63.5% patients had normal vaginal delivery, 35.0% had cesarean delivery, and 1.5% had instrumental delivery for intrapartum fetal compromise. Patients were divided into groups on the basis of Doppler findings, i.e., CPR ≤1.08 (n = 50) and CPR >1.08 (n = 150), adverse outcomes were significantly higher in groups with CPR ≤1.08 than in groups with CPR >1.08. CPR ≤1.08 was found to be 56.25% sensitive and 95.83% specific in predicting the poor outcome. Conclusion: With the high specificity and positive predictive value of CPR, it is likely that those having normal CPR will have very less chance of adverse perinatal outcomes and, therefore, their delivery can be conducted at a peripheral center, and those with low CPR should be timely referred to a higher center where there are facilities for extensive fetal monitoring during the intrapartum period with availability of the neonatal unit (NNU).