Correlation of Cerebroplacental Ratio (CPR) With Adverse Perinatal Outcome in Singleton Pregnancies

For many years clinical research has been concerned with doppler sonography as a non-invasive tool for intrauterine fetal status assessment. A new focus is now placed on the measurement of cerebroplacental index (CPR) as a predictor of fetal outcome. Our aim was to investigate the relationship between the cerebroplacental ratio (CPR), the delivery mode and the fetal outcome in singleton pregnancies.

A retrospective cohort study of pregnancies in which doppler sonography of middle cerebral artery (MCA) and umbilical artery (UA) was conducted up to 9 weeks before delivery took place. Patients with pathological (CPR≤1.0) and normal CPR (>1.0) were compared by umbilical cord pH, APGAR scores, birth weight, delivery week and delivery mode.

A total of 2,270 singleton pregnancies were included. The APGAR score for 1, 5 and 10 minutes and the gestational age at delivery were significantly lower in the group of patients with pathological CPR (p<0.001). Overall, 50% of the cohort had a cesarean section, the difference between the groups was statistically significant (p<0.001), with a higher amount of cesareans in the group of patients with pathological CPR. The multiple regression analysis showed a significantly improved pH of delivery when cesarean section (p<0.001), female sex of fetus (p=0.013) and higher CPR (p=0.035) were present.

The measurement of CPR is an important, non-invasive predictive parameter and leads to the identification of a risk collective even in the non-selected patient population and thus probably to a reduction of perinatal morbidity.