Cerebroplacental Ratio Prediction of Intrapartum Fetal Compromise according to the Interval to Delivery

Abstract

Objectives To evaluate whether the interval to delivery modifies the predictive accuracy of the cerebroplacental ratio (CPR) for the prediction of cesarean section for intrapartum fetal compromise (CS-IFC), either as a single marker or combined with estimated fetal weight centile (EFWc), type of labor onset (TLO) and other clinical variables. Material and methods This was a multicenter retrospective study of 5193 women with singleton pregnancies who underwent an ultrasound scan at 35+0- 41+0 weeks and gave birth within one month of examination, at any of the participating hospitals in Spain, UK, and Italy. CS-IFC was diagnosed in case of abnormal intrapartum fetal heart rate or intrapartum fetal scalp pH<7.20, requiring urgent cesarean section. The diagnostic ability of CPR in multiples of the median (CPR MoM) was evaluated at different intervals to delivery, alone and combined with EFWc, TLO, and other pregnancy data such as maternal age, maternal body mass index, parity, and fetal sex, for the prediction of CS-IFC by means of ROC curves and logistic regression analysis. Results The predictive ability of CPR MoM for CS-IFC worsened with the interval to delivery. In general, the best prediction was obtained prior to labor, and adding information related with EFWc and TLO [AUC 0.71 (95% CI 0.64-0.79), 0.73 (95% CI 0.66-0.80) and 0.75 (95% CI 0.69-0.81); P<0.0001]. Addition of more clinical data did not improve prediction. In addition, results did not vary when only cases with spontaneous onset of labor were studied. Conclusion CPR MoM prediction of CS-IFC at the end of pregnancy worsens with the interval to delivery. Accordingly, it should be done in the short term and considering EFWc and TLO.

Comparison of ductus venosus Doppler and cerebroplacental ratio for the prediction of adverse perinatal outcome in high‐risk pregnancies before and after 34 weeks

“…First, although for ethical reasons clinicians were not blinded to the examination, we tried to diminish this influence with additional analysis that discarded elective cesarean deliveries. Second, not only the DV Doppler, but also the CPR performs better with short intervals to labor 43 . Third, to adjust for the effect of prematurity, additional multivariable analyses were performed, including GA to rule out the effect of prematurity, or evaluating only CS‐IFC to discard unspecific neonatal admissions.…”

Cerebroplacental Ratio as a Predictive Factor of Emergency Cesarean Sections for Intrapartum Fetal Compromise: A Systematic Review

“…Eleven of them were prospective, and five were retrospective designs ( Table 1 ). Two of the studies included were multicenter [ 3 , 9 ]. The way of onset of labor was not taken into account as an inclusion criterion.…”

“…The CPR could be a way of evaluating the fetus using fetal hemodynamics, as it could reflect the fetal cerebral redistribution in response to hypoxemia, as this may occur at all centiles of fetal weight [ 2 ]. To correctly calculate the fetal Doppler, convex probes of 2–8 MHz should be used during fetal quiescence, including voluntary maternal suspended breathing, in the absence of fetal tachycardia, and keeping the insonation angle with the examined vessels as close to zero as possible [ 3 , 4 ]. The UA IP should be determined from a free-floating cord loop.…”

Fetal activity modifies middle cerebral artery pulsatility index: physiology of frequent pitfall in evaluation of fetal cerebral flow

“…Controversy exists among researchers concerning the efficiency of cerebral Doppler in the surveillance of fetal wellbeing. The accuracy of cerebral Doppler in outcome prediction has been shown to be modified by the interval to labor 1 , but other influences, such as application of different measurement procedures, may also intervene. Most examiners are aware of different factors that alter the Doppler waveform, including maternal movement and fetal breathing.…”