Purpose: As a Doppler sonographic parameter, the cerebroplacental ratio (CPR) provides information about fetal haemodynamics and the redistribution of fetal blood volume in response to a metabolic change. The present study was undertaken to determine the extent to which CPR can be used as a valid parameter in routine obstetric assessment. We investigated whether CPR can be used to assess the neonatal outcome in appropriate for gestational age (AGA) fetuses and its association with secondary caesarean section due to fetal distress.
Methods: In this retrospective analysis 1,739 pregnant women were admitted to the University Women's Clinic Magdeburg, Germany, between January 2016 and Dezember 2017. Of them, 800 were eligible for analysis. SGA fetuses with an estimated fetal weight < 10th percentile were excluded from the study. The 710 AGA fetuses were divided in two groups based on the CPR: 669 fetuses showed a normal CPR ≥ 1.08; 41 fetuses showed a decreased CPR < 1.08.
Results: In our study cohort decreased CPR in AGA fetuses was associated with threefold increased rate of caesarean sections due to fetal distress (p < 0.001). Our data suggested that low CPR is a reliable predictor of an impaired neonatal outcome in AGA fetuses in terms of a lower birth weight, transfer to neonatology, longer length of hospitalization and the presence of severe morbidity.
Conclusion: Decreased CPR in AGA fetuses correlated with impaired neonatal outcome and secondary caesarean section due to fetal distress. The potential role of CPR for obstetric screening should be investigated in further studies.