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

Abstract

Background: This systematic review aimed to clarify the association between the cerebroplacental ratio (CPR) and emergency cesarean sections (CSs) due to intrapartum fetal compromise (IFC). Methods: Datasets of PubMed, ScienceDirect, CENTRAL, Embase, and Google Scholar were searched for studies published up to January 2024 regarding the relationship between the CPR and the rate of CS for IFC, as well as the predictive value of the CPR. Results: The search identified 582 articles, of which 16 observational studies were finally included, most of them with a prospective design. A total of 14,823 patients were involved. A low CPR was associated with a higher risk of CS for IFC. The predictive value of the CPR was very different among the studies due to substantial heterogeneity regarding the group of patients included and the time interval from CPR evaluation to delivery. Conclusions: A low CPR is associated with a higher risk of CS for IFC, although with a poor predictive value. The CPR could be calculated prior to labor in all patients to stratify the risk of CS due to IFC.

Prediction of Cesarean Section for Intrapartum Fetal Compromise: A Multivariable Model from a Prospective Observational Approach

“…In the univariate analysis, the variable with the highest prediction ability for both groups was the CPR MoM (AUC 0.72). This agrees with the literature [ 5 ], although its prediction ability differs in the different works: some present similar (AUC 0.73) [ 14 ], while others present higher (AUC 0.82) [ 15 ] or lower accuracies (0.62) [ 16 ]. In addition, other authors conclude that CPR is probably unlikely to predict obstetric outcomes due to the presence of other intrapartum determinants [ 17 ].…”

“…Furthermore, in none of the published studies, an extra-specific model is performed for patients undergoing labor induction (AUC 0.80; AIC 208.3). Very few articles in literature have this ambitious goal [ 5 ]. The study with the largest sample of patients published up to now for the prediction of emergency CS includes the variables CRP, nulliparity, and induction of labor (as our model), but also the ethnicity and the EFW (AUC 0.77) [ 21 ], but did not include maternal age, height, or smoking habits.…”

“…Another published model (AUC 0.72) for the prediction of operative delivery (not CS) included several variables (gestational age at delivery, parity, CPR, labor induction, EFW, and augmentation using oxytocin), but it included just a selected population (fetuses below the 10th centile for gestational age at 36 weeks of gestation or beyond) [ 22 ]. It is also noteworthy that our group published a systematic review of CPR as a predictive factor of CS for IFC, where the predictive value of CPR was very different among the studies due to substantial heterogeneity of the patients and the disparity of the interval examination delivery [ 5 ]. In this regard, as the prediction ability of CPR has been recently shown to worsen with this interval [ 18 ], we decided to include only patients whose delivery occurred within one day of ultrasound examination.…”

“…Concerning the predictive ability of CPR for IFC, the literature shows controversial results [ 5 ], and it is still unclear which maternal parameters should also be considered to increase its prediction of CS for IFC [ 5 ]. Most of the prediction models have been developed to predict CS for failure to progress (FP) [ 6 , 7 , 8 , 9 ], and very few to predict CS for IFC [ 5 ]. Accordingly, there is insufficient scientific evidence to advise any of them in clinical practice [ 5 ].…”

“…Most of the prediction models have been developed to predict CS for failure to progress (FP) [ 6 , 7 , 8 , 9 ], and very few to predict CS for IFC [ 5 ]. Accordingly, there is insufficient scientific evidence to advise any of them in clinical practice [ 5 ].…”