Caesarean section was initially performed to save the lives of the mother and/or her baby. Caesarean section rates have risen substantially worldwide over the past decades. In this study, we set out to compile all available caesarean section rates worldwide at the country level, and to identify the appropriate caesarean section rate at the population level associated with the minimal maternal and neonatal mortality.

In the United States, there is a widespread belief that the overall cesarean birth rate is higher than necessary. Efforts are being directed toward decreasing the number of these procedures, in part by encouraging physicians to make changes in their management practices. Because breech presentations are associated with a high rate of cesarean birth, there is renewed interest in techniques such as external cephalic version (ECV) and vaginal breech delivery. The purpose of this document is to provide information about ECV by summarizing the relevant evidence presented in published studies and to make recommendations regarding its use in obstetric practice.

To create a prediction model for external cephalic version (ECV) success using objective patient characteristics.This retrospective study included pregnant individuals of at least 18 years of age with a nonanomalous, singleton gestation who underwent an ECV attempt between 2006 and 2016 at a single quaternary care hospital. Variables assessed included maternal age, height, weight, body mass index (BMI), parity, fetal sex, gestational age, estimated fetal weight, type of fetal malpresentation, placental location, and amniotic fluid volume. Univariable and multivariable logistic regression models were used to determine the association of patient characteristics with ECV success. Estimated odds ratios and corresponding 95% CIs were calculated for each variable, and backward elimination and bootstrapping were used to find a parsimonious model for ECV success with the highest discriminatory capacity (as determined by the area under the receiver operating characteristic curve [AUC]). This model was evaluated with a calibration curve across deciles of success.A total of 1,138 individuals underwent an ECV attempt and were included in this analysis. The overall ECV success frequency was 40.6%. Factors significantly associated with ECV success were maternal age, parity, placental location, estimated fetal weight, and type of fetal malpresentation. A final model with BMI, parity, placental location, and type of fetal malpresentation had the highest AUC (0.667 [95% CI 0.634-0.701]), resulted in good calibration, and is represented by the following equation: 1/[1+e-x] where x=1.1726-0.0314 (BMI)-0.9299 (nulliparity)+1.0218 (transverse or oblique presentation at ECV)-0.5113 (anterior placenta). An interactive version of this equation was created and can be accessed at www.ecvcalculator.com.A prediction model that estimates the probability of ECV success was created and internally validated. This model incorporates easily obtainable and objective patient factors known before ECV and may be used in decision making and patient counseling about ECV.Copyright © 2021 by the American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. All rights reserved.

To systematically review the medical literature reporting on ultrasound factors that can be predictive for the outcome of an attempt at external cephalic version (ECV).MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials were searched. Studies reporting on potential ultrasound prognosticators and ECV success rates that allowed construction of a 2x2 table were selected.We selected 37 primary articles reporting on 7709 women. Posterior placental location (odds ratio (OR), 1.9; 95% CI, 1.5-2.4), complete breech position (OR, 2.3; 95% CI, 1.9-2.8) and an amniotic fluid index>10 (OR, 1.8; 95% CI, 1.5-2.1) were predictors of successful ECV.Success of an ECV attempt is associated with ultrasound parameters such as fetal position, amniotic fluid and placental location. This knowledge can be used to develop a prognostic model to predict successful ECV.Copyright (c) 2008 ISUOG.

This study was undertaken to assess the association between amniotic fluid index (AFI), success of external cephalic version (ECV), and obstetric outcome in patients undergoing ECV.A prospective observational study was performed that included all patients who had a trial of ECV from 1987 to 2000 in our center. Rates of success, fetal heart decelerations during trial at ECV, and cesarean deliveries were calculated. Groups were divided by an AFI performed immediately before ECV: AFI less than 10 cm, 10 to 15 cm, and more than 15 cm.In our group of 1361 patients undergoing ECV, the rate of success was related to the AFI in both parous women (49.1%, 63.5% and 72.1% [P<.001] for each AFI group, respectively) and nulliparous women (36.5%, 43.6%, and 57.3% [P<.001]). The rate of cesarean section delivery was related to AFI in nulliparous but not multiparous patients (P<.001). The rate of prolonged fetal heart rate decelerations was not significantly related to the AFI.The rate of successful ECV and cesarean section deliveries is related to the amniotic fluid volume. This information may be used to consent patient before a trial of ECV.

External cephalic version (ECV) success correlates with numerous maternal and pregnancy factors. A prior study developed an ECV success prediction model based on body mass index, parity, placental location, and fetal presentation. We performed external validation of this model using a retrospective cohort of ECV procedures from a separate institution between July 2016 and December 2021. Four hundred thirty-four ECV procedures were performed, with a 44.4% success rate (95% CI 39.8-49.2%), which was similar to the derivation cohort (40.6%, 95% CI 37.7-43.5%, P =.16). There were significant differences in patients and practices between cohorts, including the rate of neuraxial anesthesia (83.5% derivation cohort vs 10.4% our cohort, P <.001). The area under the receiver operating characteristic curve (AUROC) was 0.70 (95% CI 0.65-0.75), which was similar to that in the derivation cohort (AUROC 0.67, 95% CI 0.63-0.70). These results suggest the published ECV prediction model's performance is generalizable outside the original study institution.Copyright © 2023 by the American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. All rights reserved.

To determine the factors associated with the success rate of external cephalic version (ECV) for breech presentation at term.A prospective analysis of 500 ECV maneuvers. The variables maternal age, maternal weight, body mass index, previous cesarean delivery, gestational age, parity, amount of amniotic fluid, placental location, and type of breech were studied using logistic regression analysis.The success rate of ECV was 52.2% (n=261). The variables significantly associated with success were parity, placental location, amount of amniotic fluid, and type of breech (P<0.05). A parity of 2 had a 3.74-times higher probability of success than nulliparity (95% CI, 2.37-5.90); a posterior placenta increased the success rate by 2.85 times compared with an anterior placenta (95% CI, 1.87-4.36); and double footling breech presentation had a 2.77-times higher success rate compared with a frank breech presentation (95% CI, 1.16-6.62). The area under the ROC curve showed a predictive ability of 73.6% (95% CI, 69.2%-77.9%) for these 3 variables.Parity, placental location, amount of amniotic fluid, and type of breech presentation were associated with the success rate of ECV.Copyright © 2010 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.