Is pathological fetal Doppler cerebroplacental ratio (CPR) associated with adverse delivery outcomes in pregnancies complicated by fetal growth restriction undergoing labor induction? A retrospective cohort study.

OBJECTIVE

The optimal delivery approach for fetal growth restriction (FGR) with pathological cerebroplacental ratio (CPR) remains uncertain. This study evaluated the association between isolated pathological CPR (<5th percentile) and delivery outcomes, specifically the rate of cesarean delivery (CD) due to non-reassuring fetal heart rate (NRFHR), in FGR cases undergoing induction of labor (IOL).

METHODS

In this retrospective cohort study (2014-2023), pregnancies with FGR (estimated fetal weight < 10th percentile) undergoing IOL were stratified by CPR values: pathological (<5th percentile) and normal CPR. Exclusion criteria included multiple gestations, abnormal umbilical artery or ductus venosus Doppler, abnormal non-stress test or biophysical profile, major fetal anomalies, and genetic disorders.

RESULTS

Among 432 FGR, 86 had pathological CPR. This group had higher rates of second-trimester human chorionic gonadotropin (HCG) >2.5 multiples of the median (11.7% vs. 3.8%, P = 0.01) and delivered earlier (37.1 vs. 38.0 weeks, P < 0.01). Overall CD rates and CD due to NRFHR were comparable between groups (19.8% vs. 18.8%, P = 0.84; 14.0% vs. 15.9%, P = 0.66, respectively). Neonates with pathological CPR had lower birthweights (2174 ± 279 g vs. 2279 ± 278 g, P < 0.01) and higher neonatal intensive care unit (NICU) admission rates (17.4% vs. 9.2%, P = 0.03). Logistic regression analysis adjusted for potential confounders showed no independent association between pathological CPR and increased risk of CD due to NRFHR (P = 0.74).

CONCLUSION

In FGR pregnancies undergoing IOL, isolated pathological CPR is not associated with an increased risk of cesarean delivery for NRFHR. However, these fetuses remain at higher risk for NICU admissions, emphasizing the need for individualized management and close monitoring.