External Cephalic Version: A Retrospective Chart Review at a Canadian Tertiary Care Centre.

OBJECTIVES: The primary objective is to identify our local external cephalic version (ECV) success rate, variables associated with increased likelihood of success, and complication rates. The secondary objective is to allow obstetrical care providers to accurately counsel patients undergoing a trial of ECV. METHODS: We analysed patient charts between January 2018 and December 2022 who underwent ECV. Variables included maternal age, parity, gestational age at the time of ECV attempt, breech type, anesthetic, uterine relaxant, placental location, neonatal birthweight, and provider seniority. Outcomes were ECV success, mode of delivery, emergent cesarean delivery rate due to ECV, and neonatal intensive care unit admission. Appropriate statistical analysis was performed. RESULTS: Overall, 258 patients were included. Overall success rate was 31%. Multiparity, transverse presentation, and neonatal birthweight >3.3 kg were associated with significantly increased success rates. Uterine relaxant use was associated with a lower success rate than no relaxant use, which is potentially explained by significantly more frequent relaxant use in non-transverse presentations and a non-significant trend in increased relaxant use in primiparous patients. Other factors including anesthetic use, maternal age, gestational age, placental location, and provider seniority did not significantly impact success. The emergency cesarean delivery rate was 10% and the neonatal intensive care unit admission rate was 8%, both of which were higher than anticipated. CONCLUSIONS: ECV remains an option for the management of the term breech. Obstetrical providers at our centre and in others may use this study to more accurately counsel patients using local data and optimize the likelihood of success based on patient and peri-procedural factors.

YouTube as a source of patient information on external cephalic version.

OBJECTIVES: To assess the quality and content of information regarding external cephalic version on YouTube. METHODS: YouTube was searched using the phrase "external cephalic version" (ECV) to identify informative videos by two independent reviewers. Videos were included if: (1) in English; (2) available November 20, 2021; (3) related to ECV. Videos were excluded if: (1) duration exceeded 15 min; (2) target audience was not patients or the general public; (3) not in English; (4) were advertisements or news clips; (5) did not relate to ECV. The Global Quality Scale was used to assess overall quality of selected videos. A content score was developed based on guidelines from the American College of Obstetricians and Gynecologists. Video quality was also categorized as "slightly useful", "useful" and "very useful". The Patient Education Materials Assessment Tool (PEMAT) for audiovisual materials was used to score understandability and actionability. RESULTS: Of 60 videos screened, 31 met inclusion criteria. They were classified as People or Blogs (n=19, 61%) or Education (n=12, 39%). Videos were calculated to be "slightly useful" (n=10, 32%), "useful" (n=18, 58%), or "very useful" (n = 3, 10%). The PEMAT - understandability was less in the "slightly useful" compared to the combined "useful" and "very useful" groups, p<0.01. No differences existed between total usefulness score and category, p=0.6. CONCLUSIONS: Most videos were useful, but few were very useful. These results highlight the importance of thorough counseling regarding this procedure.

Maternal race/ethnicity impacts the success rates of external cephalic version (ECV) in the United States.

OBJECTIVES: Racial and ethnic disparities in obstetrics are prevalent in the United States (US). We aimed to assess whether the success rate of external cephalic version (ECV) is affected by maternal race/ethnicity. METHODS: We conducted a retrospective analysis based on the CDC Natality Live Birth database for 2016-2018. We compared the success rates of ECV across US pregnant women of different racial/ethnic groups (non-Hispanic Whites, non-Hispanic Blacks, non-Hispanic Asians, and Hispanics) using the Pearson chi-square test and used multivariate logistic regression to control for confounding variables. Statistical signiciance was determined as p<0.05 and results were displayed as adjusted odds ratios (aOR) with 95% confidence intervals (95% CI). RESULTS: Of the 11,150,527 births, 26,255 women underwent an ECV and met inclusion criteria. The overall ECV success rate was 52.75% (13,850 women). Non-Hispanic Blacks had the highest ECV success rate (64.52%), followed by Hispanics (59.21%) and non-Hispanic Asians (55.51%). These rates were significantly higher than those of non-Hispanic Whites (49.27%, p<0.001). Non-Hispanic Blacks were associated with the highest success rate compared to non-Hispanic Whites (adjusted OR 1.95, 95% CI 1.77-2.15). CONCLUSIONS: The success rate of ECV varies among different maternal racial/ethnic groups. Non-Hispanic White women have the lowest ECV success rate, while non-Hispanic Black women have the highest ECV success rate.

Predictive factors for successful external cephalic version with regional anesthesia.

AIM: We aimed to investigate predictive factors of successful external cephalic version (ECV) using regional anesthesia. METHODS: In this retrospective study, we included women who underwent ECV at our center from 2010 to 2022. The procedure had been conducted using regional anesthesia and the administration of intravenous ritodrine hydrochloride. The primary outcome was the success of ECV, which was defined as the rotation from a non-cephalic to a cephalic presentation. Primary exposures were maternal demographic factors and ultrasound findings at ECV. To determine predictive factors, we conducted a logistic regression analysis. RESULTS: Of 622 pregnant women who underwent ECV, missing data on any variables (n = 14) were excluded and the remaining 608 were analyzed. The success rate during the study period was 76.3%. Multiparous women had significantly higher success rates than primiparous women (adjusted odds ratio [OR]: 2.06 [95% confidence interval (CI): 1.31-3.25]). Women with a maximum vertical pocket (MVP) of <4 cm had significantly lower success rates than those with 4 cm < MVP ≤6 cm (OR: 0.56 [95% CI: 0.37-0.86]). The non-anterior placental location was associated with higher success rates than the anterior placental location (OR: 1.46 [95% CI: 1.00-2.17]). CONCLUSIONS: Multiparity, MVP >4 cm, and non-anterior placental locations were associated with successful ECV. These three factors could be useful for patient selection for successful ECV.

Factors influencing the effect of external cephalic version: a retrospective nationwide cohort analysis.

OBJECTIVE: This study aims to assess the factors associated with the success and failure rate of the external cephalic version (ECV) in breech fetuses. Secondary outcomes were fetal presentation in labor and mode of delivery. METHODS: This cross-sectional study examined the live birth certificates from 2003 through 2020 from US states and territories that implemented the 2003 revision. A total of 149,671 singleton pregnancies with information about ECV success or failure were included. The outcome was ECV success/failure, while the exposures were possible factors associated with the outcome. RESULTS: The successful ECV procedures were 96,137 (64.23%). Among the successful ECV procedures, the prevalence of spontaneous vaginal delivery was 71.63%. Among the failed ECV procedures, 24.74% had a cephalic presentation at delivery, but 63.11% of these pregnancies were delivered by cesarean section. Nulliparity, female sex, low fetal weight centile, high pre-pregnancy BMI, high BMI at delivery, and high maternal weight gain during pregnancy were associated with an increased ECV failure (p < 0.001). African American, American Indian and Alaska Native race categories were significant protective factors against ECV failure (p < 0.001). Maternal age had a U-shape risk profile, whereas younger maternal age (< 25 years) and old maternal age (> 40 years) were significant protective factors against ECV failure (p < 0.001). CONCLUSIONS: A high prevalence of successful ECV procedures and subsequent spontaneous vaginal delivery were found. The present results found nulliparity, maternal race, maternal age, female fetal sex, low fetal weight, and maternal anthropometric features correlated to ECV results. These findings can potentially improve the knowledge about the factors involved in ECV, allowing more informed counseling to the women undergoing this procedure.

Rebozo and External Cephalic Version in breech presentation (RECEIVE): A randomised controlled study.

OBJECTIVE: To investigate if a hospital-initiated home-based rebozo intervention performed by the pregnant woman and her partner before external cephalic version (ECV) would increase the rate of cephalic presentations at birth. DESIGN: A multicentre randomised controlled trial. SETTING: Three university hospitals in Copenhagen, Denmark. POPULATION: Pregnant women with a breech or transverse presentation at 35 weeks or more of gestation eligible for ECV. METHODS: We compared rebozo before ECV with ECV alone. The randomisation was computer-generated in blocks and stratified by parity. The woman and her partner were instructed in the technique by a project midwife and performed the technique at home three times daily for 3-5 days before the scheduled ECV. Analyses were by intention-to-treat. MAIN OUTCOME MEASURE: The number of cephalic presentations at the time of birth. Odds ratios (OR) and 95% confidence intervals (CI) were calculated. RESULTS: A total of 372 women were randomly assigned (1:1) to either rebozo intervention (n = 187) or control (n = 185). At birth, 95 (51%) in the intervention group versus 112 (62%) in the control group had a fetus in cephalic presentation (OR 0.61; 95% CI 0.40-0.95). No adverse events were observed in relation to the intervention. CONCLUSIONS: In breech or transverse presentation, home-based rebozo exercise before ECV lowered the overall rate of cephalic presentation at birth. TWEETABLE ABSTRACT: Home-based rebozo for breech presentation before external version reduces the rate of cephalic presentation at birth.

Development of prediction models for successful external cephalic version and delivery outcome.

OBJECTIVE: To develop prediction models for the chance of successful external cephalic version (ECV) and delivery outcome. STUDY DESIGN: This is a single-center retrospective study including 350 pregnant women with a singleton non-cephalic pregnancy at or after 36 weeks of gestational age. We selected 22 factors for ECV prediction and 21 for delivery outcome after successful ECV prediction as candidate predictors. Multivariable logistic regression with a stepwise backward selection procedure was used to construct a prediction model for the chance of successful ECV and the other for the delivery outcome. The discrimination and calibration of the models were assessed and internal validation was done with bootstrapping. RESULTS: ECV was successfully performed in 232 cases (66.3%) among 343 women. Eight predictive factors were identified to be associated with a successful ECV: Gestational week at ECV < 39 weeks, multiparous, BMI before pregnancy < 22 kg/m3, palpable fetal head, breech engagement, larger AFI, larger BPD and posterior placenta. This model showed good calibration and good discrimination (c-statistic = 0.82, 95% CI 0.76-0.88). Six predictive factors were identified to be associated with vaginal delivery after successful ECV: age < 35, multiparous, BMI before pregnancy < 22 kg/m3, anterior placenta, lateral placenta and none-front fetal spine position. This model showed fair discrimination (c-statistic = 0.79, 95% CI 0.72-0.85). However, its calibration was not so satisfactory especially when the predicted probability was low. CONCLUSION: We validated a prediction model for ECV and delivery outcome, showing that the model's overall performance is good. This can be used in clinical practice after external validation.

External Cephalic Version-A Chance for Vaginal Delivery at Breech Presentation.

Background and Objectives: In recent years, the rate of caesarean section (CS) has increased constantly. Although vaginal breech delivery has a long history, breech presentation has become the third most common indication for CS. This study aims to identify factors associated with the success of external cephalic version (ECV), underline the success rate of ECV for breech presentation and highlight the high rate of vaginal delivery after successful ECV. Material and Methods: This retrospective observational study included 113 patients with singleton fetuses in breech presentation, who underwent ECV from January 2016 to March 2021 in the Clinic of Obstetrics and Gynecology, Diakonieklinikum Schwäbisch Hall, Germany. Maternal and fetal parameters and data related to procedure and delivery were collected. Possible predictors of successful ECV were evaluated. Results: The success rate of ECV was 54.9%. The overall rate of vaginal birth was 44.2%, regardless of ECV outcome. The vaginal birth rate after successful ECV was 80.6%. Overall, 79.0% of women with successful ECV delivered spontaneously without complications, 19.4% delivered through CS performed during labor by medical necessity, and 1.6% delivered through vacuum extraction. ECV was performed successfully in three of the four women with history of CS. Gravidity, parity, maternal age, gestational age, fetal weight, and amniotic fluid index (AFI) were significantly correlated with the outcome of ECV. Conclusions: ECV for breech presentation is a safe procedure with a good success rate, thus increasing the proportion of vaginal births. Maternal and fetal parameters can be used to estimate the chances of successful ECV.

Breech progression angle: new feasible and reliable transperineal ultrasound parameter for assessment of fetal breech descent in birth canal.

OBJECTIVE: To assess the feasibility and reliability of transperineal ultrasound in the assessment of fetal breech descent in the birth canal, by measuring the breech progression angle (BPA). METHODS: Women with a singleton pregnancy with the fetus in breech presentation between 34 and 41 weeks' gestation were recruited. Transperineal ultrasound images were acquired in the midsagittal view for each woman, twice by one operator and once by another. Each operator measured the BPA after anonymization of the transperineal ultrasound images. BPA was defined as the angle between a line running along the long axis of the pubic symphysis and another line extending from the most inferior portion of the pubic symphysis tangentially to the lowest recognizable fetal part in the maternal pelvis. Each operator was blinded to all other measurements performed for each woman. Intra- and interobserver reproducibility of BPA measurement was evaluated using the intraclass correlation coefficient (ICC). To investigate the presence of any bias, intra- and interobserver agreement was also analyzed using Bland-Altman analysis. Student's t-test and Levene's W0 test were used to investigate whether a number of different clinical factors had an effect on systematic differences and homogeneity, respectively, between BPA measurements. RESULTS: Overall, 44 women were included in the analysis. BPA was measured successfully by both operators on all images. Both intra- and interobserver agreement analyses showed excellent reproducibility in BPA measurement, with ICCs of 0.88 (95% CI, 0.80-0.93) and 0.83 (95% CI, 0.71-0.90), respectively. The mean difference between measurements was 0.4° (95% CI, -1.4 to 2.2°) for intraobserver repeatability and -0.4° (95% CI, -2.6 to 1.8°) for interobserver repeatability. The upper limits of agreement were 12.0° (95% CI, 8.9-15.1°) and 13.6° (95% CI, 9.9-17.3°) for intra- and interobserver repeatability, respectively. The lower limits of agreement were -11.2° (95% CI, -14.3 to -8.1°) and -14.4° (95% CI, -18.2 to -10.7°) for intra- and interobserver repeatability, respectively. No systematic difference between BPA measurements was found on either intra- or interobserver agreement analysis. None of the clinical factors examined (maternal body mass index, maternal age, gestational age at the ultrasound scan and parity) showed a statistically significant effect on intra- or interobserver reliability. CONCLUSIONS: BPA represents a new feasible and highly reproducible measurement for the evaluation of fetal breech descent in the birth canal. Future studies assessing its usefulness in the prediction of successful external cephalic version and breech vaginal delivery are needed. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Success rate of external cephalic version in relation to the woman's body mass index and other factors-a population-based cohort study.

INTRODUCTION: The aim of this study was to evaluate the impact of women's body mass index (BMI) on the probability of a successful external cephalic version (ECV). MATERIAL AND METHODS: A retrospective population-based observational study including all women that underwent an ECV in the southeast region of Sweden from January 2014 to December 2019. Data were collected from electronic medical records, Obstetrix, Cerner. The women were divided into BMI categories according to the World Health Organization classification. Women with a BMI below 25 kg/m2 formed the reference group. Crude and adjusted odds ratios for unsuccessful ECV in each BMI group were calculated using binary logistic regression. Furthermore, the association between maternal characteristics and clinical and ultrasound variables at the time of the ECV and unsuccessful ECV was evaluated. RESULTS: A total of 2331 women were included. The overall success rate of ECV was 53.4%. Women with a BMI below 25 kg/m2 had a success rate of 51.3% whereas obese women had a success rate of 58.6%. The risk of an unsuccessful ECV among obese women (BMI ≥30 kg/m2 ) had an OR of 0.74 (95% CI 0.59-0.94) compared with women with a BMI below 25 kg/m2 . After adjusting for suitable confounding factors, the association was no longer significant. Higher maternal age, multiparity, higher gestational age, posterior placenta position, polyhydramnios and higher estimated weight of the fetus at the ECV significantly decreased the risk of an unsuccessful ECV. CONCLUSIONS: Maternal obesity does not seem to negatively influence the success rate of ECV. This is a finding that may encourage both caregivers and obese pregnant women to consider an ECV and so avoid a planned cesarean section for breech presentation in this group.

Risk factors and outcomes of abnormal bleeding after external cephalic version.

OBJECTIVES: To present the consequences of and risk factors for abnormal bleeding after ECV (external cephalic version). METHODS: We conducted a retrospective chart review at a single center in Japan. Abnormal bleeding was defined as vaginal bleeding and/or intrauterine hemorrhage. We descriptively assessed birth outcomes among women with abnormal bleeding, and investigated the risk factors using a logistic regression analysis. RESULTS: Of 477 women who received ECV, 39 (8.2%) showed abnormal bleeding, including 16 (3.4%) with intrauterine hemorrhage. Of the 16 women with intrauterine hemorrhage, 14 required emergency cesarean section; none experienced placental abruption, a low Apgar score at 5 min (<7), or low umbilical cord artery pH (<7.1). Among 23 women who had vaginal bleeding without intrauterine hemorrhage, four cases underwent emergency cesarean section and one case of vaginal delivery involved placental abruption. The risk of abnormal bleeding was higher in women with a maximum vertical pocket (MVP) of <40 mm in comparison to those with an MVP of >50 mm (adjusted odds ratio [OR]: 3.48, 95% confidence interval [CI]: 1.23-9.90), as was higher in women with unsuccessful ECV than in those with successful ECV (aOR: 4.54, 95% CI: 1.95-10.6). CONCLUSIONS: A certain number of women who underwent ECV had abnormal bleeding, including vaginal bleeding and/or intrauterine hemorrhage, many of them resulted in emergency cesarean section. Although all of cases with abnormal bleeding had good birth outcomes, one case of vaginal bleeding was accompanied by placental abruption. Small amniotic fluid volume and unsuccessful ECV are risk factors for abnormal bleeding.

Alteration of circulating cell-free DNA level by external cephalic version: A potential biomarker for direct evaluation of placental damage.

AIM: To confirm that variations in cell-free fetal DNA (cffDNA) are indicators of external placental damage, we quantitatively investigated cffDNA alterations in maternal peripheral blood during external cephalic version (ECV). METHODS: We recruited 48 singleton pregnant women who underwent ECV in our hospital. Before and immediately after ECV, we harvested 10 ml of maternal peripheral blood samples for cffDNA analysis. cffDNA alterations were assessed based on the fetal fraction (FF) rate. We performed ECV without epidural anesthesia but administered epidural anesthesia if ECV was disrupted due to severe pain. RESULTS: The FF increased from 22.9% ± 5.7% to 27.0% ± 5.7% (p < 0.05) after ECV. The FF increased in both successful (before, 24.4% ± 5.9%; after, 28.1% ± 5.9%; p < 0.05) and unsuccessful (before, 21.8% ± 3.8%; after, 27.3% ± 4.2%; p < 0.05) cases, as well as in patients who received epidural anesthesia (before, 23.9% ± 4.7%; after, 28.5% ± 4.4%; p < 0.05) or underwent ECV more than once (before, 23.5% ± 6.1%; after, 28.4% ± 5.3%; p < 0.05). CONCLUSIONS: FF alterations increased due to external stresses during ECV; the alterations were markedly greater when the strength and duration of external stress increased. These FF alterations may serve as potential biomarkers for the direct assessment of placental damage.

Influence of the external cephalic version attempt on the Cesarean section rate: experience of a type 3 maternity hospital in France.

PURPOSE: To define the effects of attempted external cephalic version (ECV) in a low-risk population for breech delivery in a maternity hospital where breech vaginal delivery is widely practiced. MATERIALS AND METHODS: Retrospective exposed-unexposed study including 204 patients presented with a live singleton fetus breech presentation on third-trimester ultrasound and who delivered at Reims University Hospital between January 1st, 2013 and July 1st, 2018. RESULTS: 121 patients received ECV. Cesarean section rate was lower (OR with no adjustment 0.42 [0.24-0.76] p = 0.004) but without significant difference in the exposed patients after adjustment. This difference was significant between exposed and unexposed patients in the subgroup of 51 primiparous (OR = 0.14 [0.04-0.52] p = 0.002) and 51 multiparous (OR = 0.26 [0.08-0.89] p = 0.028) but not in the subgroup of 102 nulliparous. There was no difference in fetal impact other than neonatal management in the delivery room, which is less needed in exposed primiparous women. Attempted ECV significantly decreased the breech rate (72.5 vs 100%, p < 0.001). There were 7 (5.79%) complications. Three factors favored success: high uterine height (p = 0.011), a non-elevated BMI (p = 0.006) and an earlier term at ECV (p = 0.003). CONCLUSION: The attempt of ECV in the Reims University Hospital does not significantly reduce the Cesarean section rate and has no effect on neonatal status.

Efficacy of a second external cephalic version (ECV) after a successful first external cephalic version with subsequent spontaneous reinversion to breech presentation: a retrospective cohort study.

OBJECTIVE: Determining the efficacy of performance of a second external cephalic version (ECV) following successful first ECV with subsequent spontaneous reinversion to breech presentation in reducing the rate of cesarean delivery (CD). METHODS: Data were reviewed on healthy women with fetuses in breech presentation who underwent a first ECV after 36 weeks. Routine ultrasound study was performed at 39-week gestation, and a repeat ECV procedure was performed if the fetus had reverted to non-cephalic presentation. Obstetrical outcome measures were compared between women who underwent one successful ECV between 36- and 41-week gestation in which the fetus remained in cephalic presentation until labor and those who underwent a successful first ECV after which the fetus returned to breech and a second ECV was performed. The primary outcome was the rate of secondary CD during vaginal delivery in cephalic presentation; rate of successful second ECV was the secondary outcome. RESULTS: Overall 250 women underwent one ECV attempt of which 169 (67%) were successful. Of them 28 reverted to breech presentation, all women underwent two attempts of which 21 (76%) were successful. A second successful ECV attempt was associated with a 33% incidence of a CD vs. 2.8% after one successful ECV in which the fetus remained in cephalic presentation. CONCLUSION: A second ECV after a successful first ECV with subsequent spontaneous reversion to breech presentation can be expected to be successful in 76% of cases but lead to CD in 33% of cases. Our findings can be used to support patient counseling and decision-making before second ECV attempt.

Safety and efficacy of external cephalic version after a previous caesarean delivery: A systematic review.

BACKGROUND: External cephalic version (ECV) is a common procedure and has been shown to be safe and effective in turning a baby from a breech to cephalic presentation. However, whether ECV is safe and effective in women with a scarred uterus from a previous caesarean section remains contentious. AIM: To evaluate the safety and efficacy of external cephalic version in women with a singleton breech pregnancy and at least one previous caesarean delivery. MATERIAL AND METHODS: Literature searches were conducted on MEDLINE, PUBMED, EMBASE, CINAHL and SCOPUS up to June 2020. The search strategy included the following keywords: ('external cephalic version OR ECV') AND ('previous OR prior OR past' AND 'caesarean OR caesarean OR uterine scar'). Studies were included if they evaluated the efficacy and/or safety of external cephalic version in women after 36 weeks' gestation with a singleton breech pregnancy and at least one previous caesarean delivery. RESULTS: Nine studies were included in the review. ECV success rates and subsequent vaginal delivery rates ranged from 50 to 100% and from 50 to 74.9%, respectively. ECV complications reported included abnormal fetal heart rate, abnormal cardiotocography and transient vaginal bleeding. No studies reported cases of uterine rupture. CONCLUSIONS: ECV in women with a previous caesarean delivery is a relatively successful and low-risk procedure compared to women without a previous caesarean delivery. The results from this systematic review provide useful information for professional bodies in updating clinical guidelines such that ECV may be offered to women with one previous caesarean delivery.

Value of routine ultrasound examination at 35-37 weeks' gestation in diagnosis of non-cephalic presentation.

OBJECTIVE: Undiagnosed non-cephalic presentation in labor carries increased risks for both the mother and baby. Routine pregnancy care based on maternal abdominal palpation fails to detect the majority of cases of non-cephalic presentation. The aim of this study was to report the incidence of non-cephalic presentation at a routine scan at 35 + 0 to 36 + 6 weeks' gestation and the subsequent management of such pregnancies. METHODS: This was a retrospective analysis of prospectively collected data in 45 847 singleton pregnancies that had undergone routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation. Patients with breech or transverse/oblique presentation were divided into two groups; first, those who would have elective Cesarean section for fetal or maternal indications other than the abnormal presentation, and, second, those who would potentially require external cephalic version (ECV). The latter group was reassessed after 1-2 weeks and, if there was persistence of abnormal presentation, the parents were offered the option of ECV or elective Cesarean section at 38-40 weeks' gestation. Multivariable logistic regression analysis was carried out to determine which of the factors from maternal and pregnancy characteristics provided a significant contribution in the prediction of, first, non-cephalic presentation at the 35 + 0 to 36 + 6-week scan, second, successful ECV from non-cephalic to cephalic presentation, and, third, spontaneous rotation from non-cephalic to cephalic presentation that persisted until delivery. RESULTS: First, at 35 + 0 to 36 + 6 weeks, the fetal presentation was cephalic in 43 416 (94.7%) pregnancies, breech in 1987 (4.3%) and transverse or oblique in 444 (1.0%). Second, multivariable analysis demonstrated that the risk of non-cephalic presentation increased with increasing maternal age and weight, decreasing height and earlier gestational age at scan, was higher in the presence of placenta previa, oligohydramnios or polyhydramnios and in nulliparous than parous women, and was lower in women of South Asian or mixed racial origin than in white women. Third, 22% of cases of non-cephalic presentation were not eligible for ECV because of planned Cesarean section for indications other than the malpresentation. Fourth, of those eligible for ECV, only 48.5% (646/1332) agreed to the procedure, which was successful in 39.0% (252/646) of cases. Fifth, the chance of successful ECV increased with increasing maternal age and was lower in nulliparous than parous women. Sixth, in 33.9% (738/2179) of pregnancies with non-cephalic presentation in which successful ECV was not carried out, there was subsequent spontaneous rotation to cephalic presentation. Seventh, the chance of spontaneous rotation from non-cephalic to cephalic presentation increased with increasing interval between the scan and delivery, decreased with increasing birth-weight percentile, was higher in women of black than those of white racial origin, if presentation was transverse or oblique rather than breech and if there was polyhydramnios, and was lower in nulliparous than parous women and in the presence of placenta previa. Eighth, in 109 (0.3%) cephalic presentations, there was subsequent rotation to non-cephalic presentation and, in 41% of these, the diagnosis was made during labor. Ninth, of the total 2431 cases of non-cephalic presentation at the time of the scan, presentation at birth was cephalic in 985 (40.5%); in 738 (74.9%) this was due to spontaneous rotation and in 247 (25.1%) this was due to successful ECV. Tenth, prediction of non-cephalic presentation at the 35 + 0 to 36 + 6-week scan and successful ECV from maternal and pregnancy factors was poor, but prediction of spontaneous rotation from non-cephalic to cephalic presentation that persisted until delivery was moderately good and this could be incorporated in the counseling of women prior to ECV. CONCLUSIONS: The problem of unexpected non-cephalic presentation in labor can, to a great extent, be overcome by a routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation. The incidence of non-cephalic presentation at the 35 + 0 to 36 + 6-week scan was about 5%, but, in about 40% of these cases, the presentation at birth was cephalic, mainly due to subsequent spontaneous rotation and, to a lesser extent, as a consequence of successful ECV. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Effectiveness of nitrous oxide in external cephalic version on success rate: A randomized controlled trial.

INTRODUCTION: Approximately 4% of singleton pregnancies at term are in breech presentation. External cephalic version (ECV) can reduce the risks of noncephalic birth and cesarean delivery, but this maneuver can be painful. Our aim was to analyze the effect of administering inhaled nitrous oxide for analgesia on the ECV success rate. MATERIAL AND METHODS: This prospective, randomized, single-blind, controlled trial included women with singleton pregnancies in breech presentation at term who were referred for ECV in a tertiary care center. Women were assigned according to a balanced (1:1) restricted randomization design to inhale either nitrous oxide (N2 O) in a 50:50 mix with oxygen or medical air during the procedure. The main outcomes reported are the ECV success rate, degree of pain, adverse event rate, and women's satisfaction. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01948115. RESULTS: The study included 150 women (nitrous oxide group: n = 74; medical air: n = 76). Inhaled nitrous oxide was not associated with a higher ECV success rate than medical air (24.3 vs 19.7%, P = 0.51). Among parous women (n = 34 in each group), the ECV success rate appeared higher in the nitrous oxide group, respectively 47.1% (n = 16) vs 23.5% (n = 8) (P = 0.042). Neither the median pain level nor adverse event rates differed significantly in women with inhaled nitrous oxide compared with medical air. CONCLUSIONS: Use of an equimolar mixture of oxygen and nitrous oxide during ECV appears safe. Although it does not seem to change the overall success rate, it may increase success in parous women.

Management of labor after external cephalic version.

OBJECTIVES: Current literature evaluating the role of induction of labor (IOL) following successful external cephalic version (ECV) attempt as compared to expectant management is limited. We aim to assess the risk of cesarean delivery in those undergoing immediate IOL following successful ECV as compared to those who were expectantly managed. METHODS: A retrospective cohort study of successful external cephalic versions. The study group included 57 women that were induced after procedure in the lack of maternal or fetal indications for induction of labor. These women were compared to 341 expectantly managed women. Maternal and fetal characteristics and outcomes were compared. RESULTS: Gestation age at delivery was higher among the expectant management group (401/7 vs. 384/7, median, p=0.002) as compared to the induction group. Cesarean delivery rates were similar between both groups (28 [8.2%] vs. 3 [5.3%], p=0.44). In a multivariate logistic regression analysis, only nulliparity was significantly associated with cesarean delivery (adjusted odds ratio 3.42, confidence interval 1.61-7.24, p=0.001). No correlation was found between the version-to-delivery interval and the risk for cesarean delivery. CONCLUSIONS: Induction of labor after successful ECV was not shown to influence cesarean delivery rates. As immediate IOL may result in higher rate of early-term deliveries, and in light of the lack of clinical benefit, we advocate against elective IOL following successful ECV.

Prediction model of success for external cephalic version. Complications and perinatal outcomes after a successful version.

AIM: External cephalic version (ECV) is an effective and safe technique for avoiding breech presentation at birth. However, it continues rejected by many women. The aim of this study is to develop a predictive model of success of external cephalic version, determine the safety of the technique and perinatal outcomes after successful version. METHODS: Data from 317 versions performed over a 6-year period were collected. Different clinical and ultrasound variables, complications, vaginal delivery after successful version and perinatal outcomes were analyzed. RESULTS: The overall success rate was 72% (229 of 317 versions). The variables most related to success were parity, placental location, amniotic fluid volume, fetal sex, fetal head palpation and descent of the presenting part. A model for calculating the probability of success was developed in which to input parity, placentation and amniotic fluid data. The model correctly classified 98.8% of successful technique and 74% of all women. Complications were very few and mostly mild. Of women who had success, 77% (163 of 212) had a vaginal birth. No differences between neonatal outcomes were found. CONCLUSION: External cephalic version is a successful, safe technique with a high rate of subsequent vaginal delivery. A success prediction model based on some very easily obtained variables can personalize the probability of success.

Successful vaginal delivery after external cephalic version (ECV): does time interval from ECV to delivery make a difference? A multicenter study.

PURPOSE: The risk of cesarean delivery after a successful external cephalic version for breech presentation is higher as compared with fetuses in cephalic presentation. However, the role of the time interval between version attempt to delivery on the risk for cesarean delivery is unclear. We aimed to study the effect of the time interval from a successful external cephalic version to delivery on the risk for cesarean delivery and assess factors associated with cesarean delivery after a successful version. METHODS: We conducted a multicenter, retrospective cohort study, including all successful external cephalic version at two medical centers between 2011 and 2019. We compared patient baseline characteristics, obstetric characteristics, maternal and neonatal outcomes in women that delivered by vaginal delivery with those who delivered by cesarean delivery. RESULTS: Overall, 769 deliveries were included. Of these, 98 women (12.7%) had cesarean delivery and 671 (87.3%) had vaginal delivery. Women who had cesarean delivery had a higher rate of obesity (44.9% vs 21.9%, p < 0.001; OR 2.88, CI 1.65-5.03) and nulliparity (45.9% vs 24.5%, p < 0.001; OR = 2.58, CI 1.67-3.98). The risk for intrapartum cesarean delivery did not differ according to time interval from external cephalic version to delivery. CONCLUSIONS: The time interval between successful external cephalic version and delivery was not associated with mode of delivery. This finding is in contrast to previous reports. The risk for cesarean delivery after successful version is higher in nulliparous, obese women, and women whose weight gain in pregnancy was higher.