Prognostic value of the middle cerebral to umbilical artery Doppler ratio in the prediction of outcomes in post-term pregnancy

Objective. To evaluate the diagnostic value of the middle cerebral artery to umbilical artery Doppler ratio (MCA/UA ratio) in predicting poor perinatal outcomes in post-term pregnancies. Patients and methods. This study included patients diagnosed with post-term pregnancy who were admitted to the maternity hospitals in Ain Shams University and Al-Azhar University between January 2019 and December 2021. All patients underwent color Doppler velocimetry and were divided into two groups based on the MCA/UA ratio values: group A (n = 100) – MCA/UA ratio <1, and group B (n = 100) – MCA/UA ratio ≥1. Outcome factors were admission to the neonatal intensive care unit, an Apgar score of less than 7 at 5 minutes, gestational age at delivery, birth weight, and intrauterine growth restriction. Results. The MCA/UA resistance index ratio (MCA-RI/UA-RI) with a cut-off value of 0.88 was found to be the most sensitive parameter in the prediction of adverse prenatal outcomes: sensitivity – 89%, specificity – 71%, positive predictive value (PPV) – 72%, negative predictive value (NPV) – 71%. All parameters combined showed a 93% sensitivity, 92% specificity, 92% PPV, and 89% NPV. Conclusion. To enhance obstetric outcomes and prevent unnecessary treatment and perinatal death, cerebroplacental ratio appears to be a helpful indication in predicting poor neonatal outcomes in post-term pregnancy. Key words: Doppler velocimetry, middle cerebral to umbilical artery ratio, post-term pregnancy