DefinePK

Abstract

Background: The cerebroplacental ratio (CPR), derived from Doppler indices of the fetal middle cerebral artery and umbilical artery, has emerged as a potential predictor of fetal compromise. Evaluating its prognostic accuracy for adverse perinatal outcomes (APO) and cesarean section for intrapartum fetal distress (CS-IFR) may enhance perinatal risk stratification and decision-making in late gestation. Objective: To evaluate the prognostic accuracy of the cerebroplacental ratio for predicting adverse perinatal outcomes and cesarean section due to fetal distress within 24 hours of delivery. Study Design: Retrospective observational study. Setting: Radiology and Gynaecology Departments, Nishtar Hospital, Multan, Pakistan. Duration of Study: Twelve months, from April 2024 to April 2025. Methods: A total of 200 pregnant women between 31 and 41 weeks of gestation were included. All participants underwent fetal ultrasound assessment for estimated fetal weight, amniotic fluid volume, and Doppler evaluation of the umbilical artery (UA) and middle cerebral artery (MCA). The cerebroplacental ratio (CPR) was calculated as the MCA pulsatility index divided by the UA pulsatility index. Neonatal outcomes were recorded within 24 hours of delivery. Statistical analyses included chi-square tests and multiple regression analysis to determine the association between CPR and adverse outcomes. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CPR were calculated. Results: Patients with elevated UA pulsatility index and higher UA-PI multiples of the median showed a significantly higher incidence of adverse perinatal outcomes (p = 0.009). Multiple regression analysis identified labor induction (OR: 2.48, 95% CI: 1.019–6.11, p < 0.05) and CPR multiples of the median (OR: 0.03, 95% CI: 0.0071–0.3261, p < 0.001) as independent predictors of adverse perinatal outcomes. CPR showed a specificity of 70%, PPV of 32%, and NPV of 94% for predicting APO. For predicting CS-IFR, CPR had a specificity of 79%, a PPV of 26%, and NPV of 98%. Conclusion: The cerebroplacental ratio is a strong and reliable predictor of adverse perinatal outcomes and cesarean delivery for fetal distress in term pregnancies. Its high negative predictive value suggests utility in identifying low-risk pregnancies and informing delivery planning.