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Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations
G Model JOGOH 101693 No. of Pages 5
Journal of Gynecology Obstetrics and Human Reproduction xxx (2019) xxx–xxx
ScienceDirect
Original Article
Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations J. Chevreau* , A. Foulon, E. Beuvin, J. Gondry, F. Sergent Department of Obstetrics and Gynecology, University Hospital of Amiens, CHU Amiens-Picardie, Avenue Laennec, 80054 Amiens Cedex 1, France
A R T I C L E I N F O
A B S T R A C T
Article history: Received 11 October 2019 Received in revised form 15 January 2020 Accepted 16 January 2020 Available online xxx
Objective: External cephalic version (ECV) is a procedure during which the fetus is rotated from breech or transversal to cephalic presentation. Our aim was to assess the outcomes of successful ECV in terms of obstetrical and immediate neonatal outcomes relative spontaneous cephalic presentation. Methods: We performed a retrospective single-center observational study from January 2007 to December 2017. All included participants benefited from trial of labor with delivery of the fetus in cephalic presentation. They were divided into two groups depending on whether an ECV had been successfully performed or cephalic presentation was spontaneous. Results: The cephalic presentation after ECV and spontaneous cephalic groups comprised 55 and 244 patients, respectively. The two groups differed significantly in terms of the proportion of induced labor (20 [36.4 %] and 56 [22.9 %], p = 0.04), use of oxytocin during labor (31 [56.4 %] and 100 [49.9 %], p = 0.04), duration of labor (342 183 min and 279 140 min, p = 0.008), spontaneous delivery (38 [69.1 %] and 199 [81.5 %], p = 0.04), intrapartum cesarean section (9 [16.4 %] and 16 [6.6 %], p = 0.02), occiput-posterior variety at birth (20 [36.4 %] and 56 [22.9 %], p = 0.04), and brace umbilical positioning at birth (3 [5.4 %] and 2 [0.8 %], p = 0.04), respectively. There were no significant intergroup differences in terms of APGAR score, cord arterial pH/lactates, or reanimation/intensive care admission. Conclusion: A successful ECV does not seem to guaranty an identical labor progress and obstetrical outcome as spontaneous cephalic presentations. Immediate neonatal state, on the other hand, seems unaffected by a history of ECV. © 2020 Elsevier Masson SAS. All rights reserved.
Keywords: External cephalic version Outcome Breech Labor
Introduction Breech presentation represents approximately 4 % of all pregnancies at the time of birth [1]. Trial of labor for breech presentation requires an adequate medical environment and an experienced obstetrical staff, but even when all conditions are met, this situation more often results in cesarean section when compared with cephalic presentations [2–4]. External cephalic version (ECV) is a procedure during which the fetus is rotated from breech or transversal to cephalic presentation through manipulation of the maternal abdomen. The reported success is situated between 16.3 and 65 % of cases, depending on series and situations [5–7]. This procedure is generally performed between 36 and 37-weeks’ gestation (WG) to increase a woman’s chance of vaginal birth [8]. Many studies have been performed to determine risk factors for failed ECV, as well as obstetrical and neonatal outcomes of failed ECV,
* Corresponding author. E-mail address: [email protected] (J. Chevreau).
but only few have studied the outcomes of successful ECV in terms of labor progress, delivery, and immediate neonatal consequences [9,10]. This is, however, a major issue and an important aspect of the information patients should be given when considering ECV as the final outcome of this procedure should not be its immediate success but its potential impact at time of delivery. We addressed this question by conducting a retrospective comparison of trial of labor after a successful ECV with spontaneous cephalic presentations. Materials and methods This retrospective single-center observational study was performed at the Amiens-Picardie University Hospital tertiary maternity ward, France, and inclusions ran from January 2007 until December 2017. All included participants benefited from trial of labor with a fetus in cephalic presentation. They were divided into two groups, depending on whether an ECV had been successfully performed over the course of the pregnancy or cephalic presentation was spontaneous. We excluded patients presenting the following characteristics from both groups:
http://dx.doi.org/10.1016/j.jogoh.2020.101693 2468-7847/© 2020 Elsevier Masson SAS. All rights reserved.
Please cite this article in press as: J. Chevreau, et al., Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations, J Gynecol Obstet Hum Reprod (2020), https://doi.org/10.1016/j.jogoh.2020.101693
G Model JOGOH 101693 No. of Pages 5
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J. Chevreau et al. / J Gynecol Obstet Hum Reprod xxx (2019) 101693
unauthorized trial of labor, non-cephalic delivery, prior cesarean section, contra-indication for ECV, and intra-uterine fetal demise. Contra-indications for ECV in our institution were multiple pregnancies, congenital uterine malformations, fetal growth restriction, placenta previa, oligohydramnios, nuchal chord, pathological fetal rhythm, uterine contractions, and spontaneous rupture of membranes. If a non-cephalic presentation was diagnosed during the third trimester, whether during routine follow-up or a visit to the emergency ward, eligible patients received written information about the ECV procedure. If they wished a version attempt, they were given an appointment at our institution between 36 and 37 WG, after an eight-hour fast. Upon arrival, an ultrasound examination was systematically performed to assess (a) fetal presentation, and (b) presence of ECV contra-indication. If a contra-indication for ECV was diagnosed, the procedure was cancelled and a vaginal delivery trial was authorized or not, depending on the results of further investigations. ECV was performed by a senior obstetrician assisted by a resident after 2 h of external fetal cardiotocography to ensure the absence of uterine contractions or alterations of fetal cardiac rhythm, in which case the procedure was postponed or cancelled. All procedures were performed after tocolysis by salbutamol and under continuous ultrasound surveillance of fetal tolerance by heart rate monitoring. Between one and three attempts were made. Follow-up, whether ECV was successful or not, consisted of 2 h of immediate external fetal cardiotocography and, if satisfactory, the patient was allowed to leave the hospital and given an appointment for the following day during which a final 30 min of external fetal cardiotocography and a clinical examination were performed (to assess fetal presentation and cervical modification). The spontaneous cephalic presentation group was established by pairing five spontaneous cephalic presentations with one cephalic
presentation after ECV for patients for whom trial of labor was initiated in both cases. Pairing was based on the year of birth ( one year), maternal age ( one year), and term at delivery ( one WG). Pairing was automatically generated by our institution’s software after selection of the five patients having delivered immediately after the case emanating from the non-spontaneous cephalic presentation group and meeting all three paring criteria. Data are expressed as the means standard deviation (SD) for continuous variables and as numbers (percentages) for qualitative variables. Continuous variables were compared using the MannWhitney test, whereas categorical variables were compared using the χ2 test or Fisher’s exact test. Statistical analyses were performed using p-value1 freeware (https://www.pvalue.io, Paris, France). The threshold for statistical significance was p < 0.05 (two-sided). Data were obtained from our institution’s centralized electronic patient records. The study was declared and registered on the internal register of the Clinical Research and Innovation Department (DRCI) of the Amiens-Picardie University Hospital. It was registered under the number PI2019_843_0086, issued in compliance with reference methodology 004 (MR004) of the National Commission for Informatics and Liberties (CNIL) applied to projects that do not involve humans. Results During the study period, 1210 non-cephalic presentations were diagnosed during the third trimester and 184 ECVs were attempted with cephalic presentation obtained in 63 cases (success rate: 34.2 %). In 55 cases, cephalic presentation was maintained until delivery, with eight cases of spontaneous fetal version in the original breech or transversal presentation. The spontaneous cephalic group consisted of 244 patients after rejection of the
Fig. 1. Flow chart. ECV = external cephalic version. * contra-indications diagnosed before procedure: oligohydramnios (110), nuchal chord (107), uterine contractions (29), pathological fetal heart rate (4).
Please cite this article in press as: J. Chevreau, et al., Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations, J Gynecol Obstet Hum Reprod (2020), https://doi.org/10.1016/j.jogoh.2020.101693
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exclusion criteria (Fig. 1). There were no intergroup differences in terms of age, BMI, smoking status, or parity (see Table 1). Initial fetal presentations before ECV were 42 breech and 13 transversal presentations in the cephalic presentation at delivery after ECV group. Immediately after the procedure, labor was spontaneously induced in one case and hospitalization was required for a non-satisfactory fetal heart rate in two cases (both patients were released the following day). The obstetrical outcomes differed significantly between the cephalic presentation after ECV and spontaneous cephalic groups in terms of the proportion of induced labor (20 [36.4 %] and 56 [22.9 %], p = 0.04), use of oxytocin during labor (31 [56.4 %] and 100 [49.9 %], p = 0.04), duration of labor (342 183 min and 279 140 min, p = 0.008), spontaneous delivery (38 [69.1 %] and 199 [81.5 %], p = 0.04), intrapartum cesarean section (9 [16.4 %] and16 [6.6 %], p = 0.02) and occiput-posterior variety at birth (20 [36.4 %] and 56 [22.9 %], p = 0.04), respectively (Table 2). Table 1 Patient characteristics depending on whether cephalic presentation before trial of labor was spontaneous or after ECV.
n Age, years SD BMI, kg/m2 SD Active smoker, n (%) Parity, n (%): Nulliparous Multiparous
Spontaneous cephalic presentation
Cephalic presentation after ECV
244 31.5 5.02 24.2 4.54 60 (24.6)
55 31.6 5.07 24.5 4.77 16 (29.1)
73 (29.9) 171 (70.1)
10 (18.2) 45 (81.8)
p-value
0.96 0.70 0.49 0.13
BMI: body mass index; EC: external cephalic version; SD: standard deviation. Table 2 Obstetrical outcome according to whether cephalic presentation before trial of labor was spontaneous or after ECV.
n Term at delivery, WG and days, SD (days) Induction of labor, n (%): Spontaneous Induced Rupture of membranes, n (%): Spontaneous Induced Epidural analgesia, n (%) Use of Oxytocin during labor, n (%) Total duration of labor, min SD Delivery, n (%): Spontaneous vaginal delivery Assisted vaginal delivery Cesarean section Cephalic variety at vaginal delivery, n (%): Occiput-anterior Occiput-posterior Duration of expulsive efforts during vaginal delivery, min SD Perineal status in vaginal delivery, n (%): Intact Episiotomy or spontaneous tear
Spontaneous cephalic presentation
Cephalic presentation after ECV
244 39 + 5 10
55 39 + 6 9
p-value
0.86 0.04
188 (77.1) 56 (22.9)
35 (63.6) 20 (36.4) 0.18
148 (60.7) 96 (39.3) 226 (92.6) 100 (40.9)
28 (50.9) 27 (49.1) 51 (92.7) 31 (56.4)
1 0.04
279 140
342 183
0.008
199 (81.5)
38 (69.1)
0.04
29 (11.9) 16 (6.6)
8 (14.5) 9 (16.4)
0.59 0.02
223 (97.8) 5 (2.2) 11.57 7.33
42 (91.3) 4 (8.7) 14.1 9.44
0.046 0.08
0.68 10 (48.2) 118 (51.8)
19 (41.3) 27 (58.7)
ECV: external cephalic version; SD: standard deviation.
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The neonatal outcomes differed significantly between the cephalic presentation after ECV and spontaneous cephalic groups in terms of brace umbilical positioning at birth (3 [5.4 %] and 2 [0.8 %], p = 0.04) and birth weight (3395 445 g and 3237 502 g, p = 0.03), respectively (Table 3). In the cephalic presentation after ECV group, induction of labor was indicated by rupture of the membranes in 10 cases, diminished fetal movements in four, maternal indication (preeclampsia, pregnancy cholestasis, diabetes) in four, and prolonged pregnancy in two. In the spontaneous cephalic presentation group, induction of labor was indicated by rupture of the membranes in 23 cases, diminished fetal movements in seven, maternal indication (preeclampsia, pregnancy cholestasis, diabetes) in 14, and prolonged pregnancy in 12. In the cephalic presentation after ECV group, indications for assisted vaginal delivery were altered fetal heart rate in two cases, non-progression of fetal presentation during expulsion efforts in four, and a combination of both in two. In the spontaneous cephalic presentation group, indications for assisted vaginal delivery were altered fetal heart rate in 11 cases, non-progression of fetal presentation during expulsion efforts in eight, and a combination of both in 10. In the cephalic presentation after ECV group, indications for intrapartum cesarean section were altered fetal heart rate in five cases, prolonged first stage of labor in two, and the absence of cephalic engagement in two. In the spontaneous cephalic presentation group, indications for intrapartum cesarean sectionwere altered fetal heart rate in 13 cases, prolonged first stage of labor in two, and the absence of cephalic engagement in one. Discussion The cephalic presentation after ECV and spontaneous cephalic groups differed significantly in terms of obstetrical outcome
Table 3 Neonatal outcome according to whether cephalic presentation before trial of labor was spontaneous or after ECV.
n Fetal cardiac rhythm during labor, n (%): Normal Altered, necessitating a secondary means of surveillance* Altered, necessitating emergency extraction Umbilical abnormalities, n (%): Short umbilical cord Nuchal cord Brace Amniotic fluid color, n (%): Clear Stained Meconial Bloody Birth weight, g SD Cephalic circumference, cm SD APGAR score, n (%): <7 at 1 min <7 at 5 min Cord arterial pH < 7.20, n (%) Cord arterial lactates, mean SD Reanimation or intensive care unit admission, n (%)
Spontaneous cephalic presentation
Cephalic presentation after ECV
244
55
p-value
0.54 213 (87.3) 13 (5.3)
45 (81.8) 4 (7.3)
18 (7.4)
6 (10.9)
4 (1.6) 48 (19.7) 2 (0.8)
0 16 (29) 3 (5.4)
217 (88.9) 19 (7.8) 8 (3.3) 0 3395 445 34.7 1.16
48 (87.3) 5 (9.1) 2 (3.6) 0 3237 502 34.8 1.34
0.03 0.53
9 (3.7) 0 17 (7.2) 3.56 2.14
1 (1.8) 1 (1.8) 7 (13.5) 3.62 2.16
0.69 0.16 0.86
10 (4.1)
6 (10.9)
0.08
0.14 0.04 0.87
* Fetal scalp pH or fetal electrocardiography ST analysis; ECV: external cephalic version; SD: standard deviation.
Please cite this article in press as: J. Chevreau, et al., Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations, J Gynecol Obstet Hum Reprod (2020), https://doi.org/10.1016/j.jogoh.2020.101693
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regarding induction of labor, use of oxytocin during labor, duration of labor, assisted and cesarean deliveries, with a less favorable outcome in case of non-spontaneous cephalic presentations. Immediate neonatal outcome was, on the other hand, unaffected. ECV’s aim is to decrease potential negative repercussions of trial of labor in case of breech presentation. Even though it has been thoroughly demonstrated that such a presentation does not justify a systematic elective cesarean, which explains why most national obstetrical societies have recommended trial of labor when all acceptability criteria were met, obstetrical and neonatal well-being appear to be improved by successful ECV [2–4,11–16]. Regarding obstetrical outcome, labor was more arduous, even though the ECV group consisted (non-significantly) of a higher proportion of multiparous patients. Labor was also less spontaneous (with identical proportions of spontaneous rupture of membranes), longer, and required more frequent use of oxytocin. Delivery was less frequently unassisted and intrapartum cesarean section more frequent. Several factors could explain these observations. First, it has been established that breech presentation is favored by certain determinants. In a population-based cohort study on 28,059 breech deliveries, Cammu et al. found that a low birth weight, an advanced maternal age, a scarred uterus, a female baby, and a baby with a congenital malformation increased the odds for singleton breech presentation at parturition [17]. Other well-known causes for breech presentations are uterus related, such as uterine anomalies (mostly septate or bicornuate uteri), or the presence of leiomyomas, as they could prevent spontaneous fetal version [18,19]. Regardless of the cause, it is highly probable that the breech determinant, as it is still present after a successful ECV, may also be responsible for a higher proportion of dystocic cephalic presentations, as observed in our study, in which occiput posterior cephalic variety was more frequent in the after-ECV cephalic presentation group. Dystocic cephalic varieties are proven factors for longer labor, assisted vaginal delivery, and intrapartum cesarean delivery. This could thus partially explain why the obstetrical outcomes in cases of successful ECV were not as favorable as with spontaneous cephalic presentations [20–23]. Another possible explanation for poorer obstetrical outcomes in cases of cephalic presentation after ECV relative to spontaneous cephalic presentations could be that, as the fetus is mobilized during the procedure, the umbilical cord is dragged along, sometimes resulting in dystocic cord positioning. This may explain why we observed a higher proportion of brace and nuchal cord positioning in the non-spontaneous cephalic fetal presentations. Such dystocic cord positioning has also been shown to have a negative impact on obstetrical outcomes, as reported by Ogueh et al. in a study in which 13,717 pregnancies with nuchal cord were compared to 44,136 without nuchal cord [24]. As with the induced cephalic presentations in our study, a greater proportion of pregnant women with fetal nuchal cord underwent induced labor (adjusted OR 1.09, 95 % CI 1.04–1.15) and had a longer second stage of labor (p = 0.0013). As stated before, only few studies have evaluated the impact of successful ECVs in comparison to spontaneous cephalic presentations. Nevertheless, current literature does seem to validate our results. Indeed, in a recent retrospective cohort study comparing 47 successful ECVs to a control group comprising 7456 singleton spontaneous cephalic pregnancies over 37 WG, de Gregorio et al. reported similar results with a rate of cesarean sections higher after successful ECV compared to spontaneous cephalic presentation (27.7 vs. 12.8 %, OR 2.615). In this study, neonatal outcome was also unaffected by a successful ECV [9]. In another retrospective study evaluating obstetrical outcome after induction of labor, patients having benefited from a successful ECV were shown to present an increased risk of cesarean section (aOR 1.946; 95 % CI 1.017–3.772) [10].
Our study had certain limitations. First, the fact that certain exclusion criteria were present after pairing in the control group could have an impact on the internal validity of our results, even if those 31 patients were excluded from statistical analyses. Limitations were also present regarding neonatal outcomes. Indeed, the only available markers for neonatal well-being were immediate after-birth data which, although objective measures, do not always reflect future development. Also, our results showed a higher proportion of arterial cord pH < 7.20 and admittance to reanimation or intensive care units when an ECV procedure was performed. These intergroup differences were not significant, potentially due to a lack of statistical power, which calls for other studies with larger cohorts. This observation also applied to obstetrical outcomes, as some differences just failed to surpass the 0.05 threshold, such as the duration of expulsive efforts, which were longer when ECV was performed, even though this group did not consist of more nulliparous patients or heavier newborns. Nevertheless, our results still showed that a successful ECV does not seem to guaranty an identical labor progress and/or obstetrical outcome as spontaneous cephalic presentations. This information should be delivered to patients contemplating such a procedure in order to allow a fully advised decision. Declaration of Competing Interest The authors declare no conflict of interest concerning this article. References [1] Hickok DE, Gordon DC, Milberg JA, Williams MA, Daling JR. The frequency of breech presentation by gestational age at birth: a large population-based study. Am J Obstet Gynecol 1992;166:851–2. [2] Macharey G, Väisänen-Tommiska M, Gissler M, Ulander VM, Rahkonen L, Nuutila M, et al. Neurodevelopmental outcome at the age of 4 years according to the planned mode of delivery in term breech presentation: a nationwide, population-based record linkage study. J Perinat Med 2018;46:323–31. [3] Chevreau J, Foulon A, Abou Arab O, Luisin M, Parent C, Sergent F, et al. Management of breech and twin labor during registrarship: a two-year prospective, observational study. J Gynecol Obstet Hum Reprod 2018;47:191–6. [4] Toivonen E, Palomäki O, Huhtala H, Uotila J. Maternal experiences of vaginal breech delivery. Birth 2014;41:316–22. [5] Grootscholten K, Kok M, Oei SG, Mol BW, van der Post JA. External cephalic version-related risks: a meta-analysis. Obstet Gynecol 2008;112:1143–51. [6] Hofmeyr GJ, Kulier R, West HM. External cephalic version for breech presentation at term. Cochrane Database Syst Rev 2015(4)CD000083 Apr 1. [7] Dochez V, Delbos L, Esbelin J, Volteau C, Winer N, Sentilhes L. Predictors of success of external cephalic version: Bi-center study. J Gynecol Obstet Biol Reprod 2016;45:509–15. [8] American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins–Obstetrics. Practice Bulletin No. 161: external cephalic version. Obstet Gynecol 2016;127:e54–61. [9] de Gregorio N, Friedl T, Schramm A, Reister F, Janni W, Ebner F. Comparison of fetomaternal outcome between 47 deliveries following successful external cephalic version for breech presentation and 7456 deliveries following spontaneous cephalic presentation. Gynecol Obstet Invest 2018;8:477–81. [10] Boujenah J, Fleury C, Pharisien I, Benbara A, Benchimol M, Carbillon L. Induction du travail après une version par manœuvres externes pour siège réussie : un sur-risque de césarienne? J Obstet Gynaecol Can 2018;40:1031–7. [11] Hofmeyr GJ, Hannah M, Lawrie TA. Planned caesarean section for term breech delivery. Cochrane Database Syst Rev 2015;7:1–62. [12] Berhan Y, Haileamlak A. The risks of planned vaginal breech delivery versus planned caesarean section for term breech birth: a meta-analysis including observational studies. BJOG 2016;123:49–57. [13] Goffinet F, Carayol M, Foidart JM, Alexander S, Uzan S, Subtil D, et al. Is planned vaginal delivery for breech presentation at term still an option? Results of an observational prospective survey in France and Belgium. Am J Obstet Gynecol 2006;194:1002–11. [14] D’Ercole C. CNGOF – mises à jour en gyne’cologie et obste’trique et techniques chirurgicales. Paris: Diffusion Vigot-Paris 2011;195–218. [15] American College of Obstetricians and Gynecologists, Society for MaternalFetal Medicine. Obstetric care consensus no. 1: safe prevention of the primary cesarean delivery. Obstet Gynecol 2014;123:693–711. [16] Breton A, Gueudry P, Branger B, Le F, Thubert T, Arthuis C, et al. Comparison of obstetric prognosis of attempts of breech delivery: spontaneous labor versus induced labor. Gynecol Obstet Fertil Senol 2018;46:632–8.
Please cite this article in press as: J. Chevreau, et al., Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations, J Gynecol Obstet Hum Reprod (2020), https://doi.org/10.1016/j.jogoh.2020.101693
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Please cite this article in press as: J. Chevreau, et al., Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations, J Gynecol Obstet Hum Reprod (2020), https://doi.org/10.1016/j.jogoh.2020.101693
Journal of Gynecology Obstetrics and Human Reproduction xxx (2019) xxx–xxx
ScienceDirect
Original Article
Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations J. Chevreau* , A. Foulon, E. Beuvin, J. Gondry, F. Sergent Department of Obstetrics and Gynecology, University Hospital of Amiens, CHU Amiens-Picardie, Avenue Laennec, 80054 Amiens Cedex 1, France
A R T I C L E I N F O
A B S T R A C T
Article history: Received 11 October 2019 Received in revised form 15 January 2020 Accepted 16 January 2020 Available online xxx
Objective: External cephalic version (ECV) is a procedure during which the fetus is rotated from breech or transversal to cephalic presentation. Our aim was to assess the outcomes of successful ECV in terms of obstetrical and immediate neonatal outcomes relative spontaneous cephalic presentation. Methods: We performed a retrospective single-center observational study from January 2007 to December 2017. All included participants benefited from trial of labor with delivery of the fetus in cephalic presentation. They were divided into two groups depending on whether an ECV had been successfully performed or cephalic presentation was spontaneous. Results: The cephalic presentation after ECV and spontaneous cephalic groups comprised 55 and 244 patients, respectively. The two groups differed significantly in terms of the proportion of induced labor (20 [36.4 %] and 56 [22.9 %], p = 0.04), use of oxytocin during labor (31 [56.4 %] and 100 [49.9 %], p = 0.04), duration of labor (342 183 min and 279 140 min, p = 0.008), spontaneous delivery (38 [69.1 %] and 199 [81.5 %], p = 0.04), intrapartum cesarean section (9 [16.4 %] and 16 [6.6 %], p = 0.02), occiput-posterior variety at birth (20 [36.4 %] and 56 [22.9 %], p = 0.04), and brace umbilical positioning at birth (3 [5.4 %] and 2 [0.8 %], p = 0.04), respectively. There were no significant intergroup differences in terms of APGAR score, cord arterial pH/lactates, or reanimation/intensive care admission. Conclusion: A successful ECV does not seem to guaranty an identical labor progress and obstetrical outcome as spontaneous cephalic presentations. Immediate neonatal state, on the other hand, seems unaffected by a history of ECV. © 2020 Elsevier Masson SAS. All rights reserved.
Keywords: External cephalic version Outcome Breech Labor
Introduction Breech presentation represents approximately 4 % of all pregnancies at the time of birth [1]. Trial of labor for breech presentation requires an adequate medical environment and an experienced obstetrical staff, but even when all conditions are met, this situation more often results in cesarean section when compared with cephalic presentations [2–4]. External cephalic version (ECV) is a procedure during which the fetus is rotated from breech or transversal to cephalic presentation through manipulation of the maternal abdomen. The reported success is situated between 16.3 and 65 % of cases, depending on series and situations [5–7]. This procedure is generally performed between 36 and 37-weeks’ gestation (WG) to increase a woman’s chance of vaginal birth [8]. Many studies have been performed to determine risk factors for failed ECV, as well as obstetrical and neonatal outcomes of failed ECV,
* Corresponding author. E-mail address: [email protected] (J. Chevreau).
but only few have studied the outcomes of successful ECV in terms of labor progress, delivery, and immediate neonatal consequences [9,10]. This is, however, a major issue and an important aspect of the information patients should be given when considering ECV as the final outcome of this procedure should not be its immediate success but its potential impact at time of delivery. We addressed this question by conducting a retrospective comparison of trial of labor after a successful ECV with spontaneous cephalic presentations. Materials and methods This retrospective single-center observational study was performed at the Amiens-Picardie University Hospital tertiary maternity ward, France, and inclusions ran from January 2007 until December 2017. All included participants benefited from trial of labor with a fetus in cephalic presentation. They were divided into two groups, depending on whether an ECV had been successfully performed over the course of the pregnancy or cephalic presentation was spontaneous. We excluded patients presenting the following characteristics from both groups:
http://dx.doi.org/10.1016/j.jogoh.2020.101693 2468-7847/© 2020 Elsevier Masson SAS. All rights reserved.
Please cite this article in press as: J. Chevreau, et al., Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations, J Gynecol Obstet Hum Reprod (2020), https://doi.org/10.1016/j.jogoh.2020.101693
G Model JOGOH 101693 No. of Pages 5
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unauthorized trial of labor, non-cephalic delivery, prior cesarean section, contra-indication for ECV, and intra-uterine fetal demise. Contra-indications for ECV in our institution were multiple pregnancies, congenital uterine malformations, fetal growth restriction, placenta previa, oligohydramnios, nuchal chord, pathological fetal rhythm, uterine contractions, and spontaneous rupture of membranes. If a non-cephalic presentation was diagnosed during the third trimester, whether during routine follow-up or a visit to the emergency ward, eligible patients received written information about the ECV procedure. If they wished a version attempt, they were given an appointment at our institution between 36 and 37 WG, after an eight-hour fast. Upon arrival, an ultrasound examination was systematically performed to assess (a) fetal presentation, and (b) presence of ECV contra-indication. If a contra-indication for ECV was diagnosed, the procedure was cancelled and a vaginal delivery trial was authorized or not, depending on the results of further investigations. ECV was performed by a senior obstetrician assisted by a resident after 2 h of external fetal cardiotocography to ensure the absence of uterine contractions or alterations of fetal cardiac rhythm, in which case the procedure was postponed or cancelled. All procedures were performed after tocolysis by salbutamol and under continuous ultrasound surveillance of fetal tolerance by heart rate monitoring. Between one and three attempts were made. Follow-up, whether ECV was successful or not, consisted of 2 h of immediate external fetal cardiotocography and, if satisfactory, the patient was allowed to leave the hospital and given an appointment for the following day during which a final 30 min of external fetal cardiotocography and a clinical examination were performed (to assess fetal presentation and cervical modification). The spontaneous cephalic presentation group was established by pairing five spontaneous cephalic presentations with one cephalic
presentation after ECV for patients for whom trial of labor was initiated in both cases. Pairing was based on the year of birth ( one year), maternal age ( one year), and term at delivery ( one WG). Pairing was automatically generated by our institution’s software after selection of the five patients having delivered immediately after the case emanating from the non-spontaneous cephalic presentation group and meeting all three paring criteria. Data are expressed as the means standard deviation (SD) for continuous variables and as numbers (percentages) for qualitative variables. Continuous variables were compared using the MannWhitney test, whereas categorical variables were compared using the χ2 test or Fisher’s exact test. Statistical analyses were performed using p-value1 freeware (https://www.pvalue.io, Paris, France). The threshold for statistical significance was p < 0.05 (two-sided). Data were obtained from our institution’s centralized electronic patient records. The study was declared and registered on the internal register of the Clinical Research and Innovation Department (DRCI) of the Amiens-Picardie University Hospital. It was registered under the number PI2019_843_0086, issued in compliance with reference methodology 004 (MR004) of the National Commission for Informatics and Liberties (CNIL) applied to projects that do not involve humans. Results During the study period, 1210 non-cephalic presentations were diagnosed during the third trimester and 184 ECVs were attempted with cephalic presentation obtained in 63 cases (success rate: 34.2 %). In 55 cases, cephalic presentation was maintained until delivery, with eight cases of spontaneous fetal version in the original breech or transversal presentation. The spontaneous cephalic group consisted of 244 patients after rejection of the
Fig. 1. Flow chart. ECV = external cephalic version. * contra-indications diagnosed before procedure: oligohydramnios (110), nuchal chord (107), uterine contractions (29), pathological fetal heart rate (4).
Please cite this article in press as: J. Chevreau, et al., Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations, J Gynecol Obstet Hum Reprod (2020), https://doi.org/10.1016/j.jogoh.2020.101693
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exclusion criteria (Fig. 1). There were no intergroup differences in terms of age, BMI, smoking status, or parity (see Table 1). Initial fetal presentations before ECV were 42 breech and 13 transversal presentations in the cephalic presentation at delivery after ECV group. Immediately after the procedure, labor was spontaneously induced in one case and hospitalization was required for a non-satisfactory fetal heart rate in two cases (both patients were released the following day). The obstetrical outcomes differed significantly between the cephalic presentation after ECV and spontaneous cephalic groups in terms of the proportion of induced labor (20 [36.4 %] and 56 [22.9 %], p = 0.04), use of oxytocin during labor (31 [56.4 %] and 100 [49.9 %], p = 0.04), duration of labor (342 183 min and 279 140 min, p = 0.008), spontaneous delivery (38 [69.1 %] and 199 [81.5 %], p = 0.04), intrapartum cesarean section (9 [16.4 %] and16 [6.6 %], p = 0.02) and occiput-posterior variety at birth (20 [36.4 %] and 56 [22.9 %], p = 0.04), respectively (Table 2). Table 1 Patient characteristics depending on whether cephalic presentation before trial of labor was spontaneous or after ECV.
n Age, years SD BMI, kg/m2 SD Active smoker, n (%) Parity, n (%): Nulliparous Multiparous
Spontaneous cephalic presentation
Cephalic presentation after ECV
244 31.5 5.02 24.2 4.54 60 (24.6)
55 31.6 5.07 24.5 4.77 16 (29.1)
73 (29.9) 171 (70.1)
10 (18.2) 45 (81.8)
p-value
0.96 0.70 0.49 0.13
BMI: body mass index; EC: external cephalic version; SD: standard deviation. Table 2 Obstetrical outcome according to whether cephalic presentation before trial of labor was spontaneous or after ECV.
n Term at delivery, WG and days, SD (days) Induction of labor, n (%): Spontaneous Induced Rupture of membranes, n (%): Spontaneous Induced Epidural analgesia, n (%) Use of Oxytocin during labor, n (%) Total duration of labor, min SD Delivery, n (%): Spontaneous vaginal delivery Assisted vaginal delivery Cesarean section Cephalic variety at vaginal delivery, n (%): Occiput-anterior Occiput-posterior Duration of expulsive efforts during vaginal delivery, min SD Perineal status in vaginal delivery, n (%): Intact Episiotomy or spontaneous tear
Spontaneous cephalic presentation
Cephalic presentation after ECV
244 39 + 5 10
55 39 + 6 9
p-value
0.86 0.04
188 (77.1) 56 (22.9)
35 (63.6) 20 (36.4) 0.18
148 (60.7) 96 (39.3) 226 (92.6) 100 (40.9)
28 (50.9) 27 (49.1) 51 (92.7) 31 (56.4)
1 0.04
279 140
342 183
0.008
199 (81.5)
38 (69.1)
0.04
29 (11.9) 16 (6.6)
8 (14.5) 9 (16.4)
0.59 0.02
223 (97.8) 5 (2.2) 11.57 7.33
42 (91.3) 4 (8.7) 14.1 9.44
0.046 0.08
0.68 10 (48.2) 118 (51.8)
19 (41.3) 27 (58.7)
ECV: external cephalic version; SD: standard deviation.
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The neonatal outcomes differed significantly between the cephalic presentation after ECV and spontaneous cephalic groups in terms of brace umbilical positioning at birth (3 [5.4 %] and 2 [0.8 %], p = 0.04) and birth weight (3395 445 g and 3237 502 g, p = 0.03), respectively (Table 3). In the cephalic presentation after ECV group, induction of labor was indicated by rupture of the membranes in 10 cases, diminished fetal movements in four, maternal indication (preeclampsia, pregnancy cholestasis, diabetes) in four, and prolonged pregnancy in two. In the spontaneous cephalic presentation group, induction of labor was indicated by rupture of the membranes in 23 cases, diminished fetal movements in seven, maternal indication (preeclampsia, pregnancy cholestasis, diabetes) in 14, and prolonged pregnancy in 12. In the cephalic presentation after ECV group, indications for assisted vaginal delivery were altered fetal heart rate in two cases, non-progression of fetal presentation during expulsion efforts in four, and a combination of both in two. In the spontaneous cephalic presentation group, indications for assisted vaginal delivery were altered fetal heart rate in 11 cases, non-progression of fetal presentation during expulsion efforts in eight, and a combination of both in 10. In the cephalic presentation after ECV group, indications for intrapartum cesarean section were altered fetal heart rate in five cases, prolonged first stage of labor in two, and the absence of cephalic engagement in two. In the spontaneous cephalic presentation group, indications for intrapartum cesarean sectionwere altered fetal heart rate in 13 cases, prolonged first stage of labor in two, and the absence of cephalic engagement in one. Discussion The cephalic presentation after ECV and spontaneous cephalic groups differed significantly in terms of obstetrical outcome
Table 3 Neonatal outcome according to whether cephalic presentation before trial of labor was spontaneous or after ECV.
n Fetal cardiac rhythm during labor, n (%): Normal Altered, necessitating a secondary means of surveillance* Altered, necessitating emergency extraction Umbilical abnormalities, n (%): Short umbilical cord Nuchal cord Brace Amniotic fluid color, n (%): Clear Stained Meconial Bloody Birth weight, g SD Cephalic circumference, cm SD APGAR score, n (%): <7 at 1 min <7 at 5 min Cord arterial pH < 7.20, n (%) Cord arterial lactates, mean SD Reanimation or intensive care unit admission, n (%)
Spontaneous cephalic presentation
Cephalic presentation after ECV
244
55
p-value
0.54 213 (87.3) 13 (5.3)
45 (81.8) 4 (7.3)
18 (7.4)
6 (10.9)
4 (1.6) 48 (19.7) 2 (0.8)
0 16 (29) 3 (5.4)
217 (88.9) 19 (7.8) 8 (3.3) 0 3395 445 34.7 1.16
48 (87.3) 5 (9.1) 2 (3.6) 0 3237 502 34.8 1.34
0.03 0.53
9 (3.7) 0 17 (7.2) 3.56 2.14
1 (1.8) 1 (1.8) 7 (13.5) 3.62 2.16
0.69 0.16 0.86
10 (4.1)
6 (10.9)
0.08
0.14 0.04 0.87
* Fetal scalp pH or fetal electrocardiography ST analysis; ECV: external cephalic version; SD: standard deviation.
Please cite this article in press as: J. Chevreau, et al., Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations, J Gynecol Obstet Hum Reprod (2020), https://doi.org/10.1016/j.jogoh.2020.101693
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regarding induction of labor, use of oxytocin during labor, duration of labor, assisted and cesarean deliveries, with a less favorable outcome in case of non-spontaneous cephalic presentations. Immediate neonatal outcome was, on the other hand, unaffected. ECV’s aim is to decrease potential negative repercussions of trial of labor in case of breech presentation. Even though it has been thoroughly demonstrated that such a presentation does not justify a systematic elective cesarean, which explains why most national obstetrical societies have recommended trial of labor when all acceptability criteria were met, obstetrical and neonatal well-being appear to be improved by successful ECV [2–4,11–16]. Regarding obstetrical outcome, labor was more arduous, even though the ECV group consisted (non-significantly) of a higher proportion of multiparous patients. Labor was also less spontaneous (with identical proportions of spontaneous rupture of membranes), longer, and required more frequent use of oxytocin. Delivery was less frequently unassisted and intrapartum cesarean section more frequent. Several factors could explain these observations. First, it has been established that breech presentation is favored by certain determinants. In a population-based cohort study on 28,059 breech deliveries, Cammu et al. found that a low birth weight, an advanced maternal age, a scarred uterus, a female baby, and a baby with a congenital malformation increased the odds for singleton breech presentation at parturition [17]. Other well-known causes for breech presentations are uterus related, such as uterine anomalies (mostly septate or bicornuate uteri), or the presence of leiomyomas, as they could prevent spontaneous fetal version [18,19]. Regardless of the cause, it is highly probable that the breech determinant, as it is still present after a successful ECV, may also be responsible for a higher proportion of dystocic cephalic presentations, as observed in our study, in which occiput posterior cephalic variety was more frequent in the after-ECV cephalic presentation group. Dystocic cephalic varieties are proven factors for longer labor, assisted vaginal delivery, and intrapartum cesarean delivery. This could thus partially explain why the obstetrical outcomes in cases of successful ECV were not as favorable as with spontaneous cephalic presentations [20–23]. Another possible explanation for poorer obstetrical outcomes in cases of cephalic presentation after ECV relative to spontaneous cephalic presentations could be that, as the fetus is mobilized during the procedure, the umbilical cord is dragged along, sometimes resulting in dystocic cord positioning. This may explain why we observed a higher proportion of brace and nuchal cord positioning in the non-spontaneous cephalic fetal presentations. Such dystocic cord positioning has also been shown to have a negative impact on obstetrical outcomes, as reported by Ogueh et al. in a study in which 13,717 pregnancies with nuchal cord were compared to 44,136 without nuchal cord [24]. As with the induced cephalic presentations in our study, a greater proportion of pregnant women with fetal nuchal cord underwent induced labor (adjusted OR 1.09, 95 % CI 1.04–1.15) and had a longer second stage of labor (p = 0.0013). As stated before, only few studies have evaluated the impact of successful ECVs in comparison to spontaneous cephalic presentations. Nevertheless, current literature does seem to validate our results. Indeed, in a recent retrospective cohort study comparing 47 successful ECVs to a control group comprising 7456 singleton spontaneous cephalic pregnancies over 37 WG, de Gregorio et al. reported similar results with a rate of cesarean sections higher after successful ECV compared to spontaneous cephalic presentation (27.7 vs. 12.8 %, OR 2.615). In this study, neonatal outcome was also unaffected by a successful ECV [9]. In another retrospective study evaluating obstetrical outcome after induction of labor, patients having benefited from a successful ECV were shown to present an increased risk of cesarean section (aOR 1.946; 95 % CI 1.017–3.772) [10].
Our study had certain limitations. First, the fact that certain exclusion criteria were present after pairing in the control group could have an impact on the internal validity of our results, even if those 31 patients were excluded from statistical analyses. Limitations were also present regarding neonatal outcomes. Indeed, the only available markers for neonatal well-being were immediate after-birth data which, although objective measures, do not always reflect future development. Also, our results showed a higher proportion of arterial cord pH < 7.20 and admittance to reanimation or intensive care units when an ECV procedure was performed. These intergroup differences were not significant, potentially due to a lack of statistical power, which calls for other studies with larger cohorts. This observation also applied to obstetrical outcomes, as some differences just failed to surpass the 0.05 threshold, such as the duration of expulsive efforts, which were longer when ECV was performed, even though this group did not consist of more nulliparous patients or heavier newborns. Nevertheless, our results still showed that a successful ECV does not seem to guaranty an identical labor progress and/or obstetrical outcome as spontaneous cephalic presentations. This information should be delivered to patients contemplating such a procedure in order to allow a fully advised decision. Declaration of Competing Interest The authors declare no conflict of interest concerning this article. References [1] Hickok DE, Gordon DC, Milberg JA, Williams MA, Daling JR. The frequency of breech presentation by gestational age at birth: a large population-based study. Am J Obstet Gynecol 1992;166:851–2. [2] Macharey G, Väisänen-Tommiska M, Gissler M, Ulander VM, Rahkonen L, Nuutila M, et al. Neurodevelopmental outcome at the age of 4 years according to the planned mode of delivery in term breech presentation: a nationwide, population-based record linkage study. J Perinat Med 2018;46:323–31. [3] Chevreau J, Foulon A, Abou Arab O, Luisin M, Parent C, Sergent F, et al. Management of breech and twin labor during registrarship: a two-year prospective, observational study. J Gynecol Obstet Hum Reprod 2018;47:191–6. [4] Toivonen E, Palomäki O, Huhtala H, Uotila J. Maternal experiences of vaginal breech delivery. Birth 2014;41:316–22. [5] Grootscholten K, Kok M, Oei SG, Mol BW, van der Post JA. External cephalic version-related risks: a meta-analysis. Obstet Gynecol 2008;112:1143–51. [6] Hofmeyr GJ, Kulier R, West HM. External cephalic version for breech presentation at term. Cochrane Database Syst Rev 2015(4)CD000083 Apr 1. [7] Dochez V, Delbos L, Esbelin J, Volteau C, Winer N, Sentilhes L. Predictors of success of external cephalic version: Bi-center study. J Gynecol Obstet Biol Reprod 2016;45:509–15. [8] American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins–Obstetrics. Practice Bulletin No. 161: external cephalic version. Obstet Gynecol 2016;127:e54–61. [9] de Gregorio N, Friedl T, Schramm A, Reister F, Janni W, Ebner F. Comparison of fetomaternal outcome between 47 deliveries following successful external cephalic version for breech presentation and 7456 deliveries following spontaneous cephalic presentation. Gynecol Obstet Invest 2018;8:477–81. [10] Boujenah J, Fleury C, Pharisien I, Benbara A, Benchimol M, Carbillon L. Induction du travail après une version par manœuvres externes pour siège réussie : un sur-risque de césarienne? J Obstet Gynaecol Can 2018;40:1031–7. [11] Hofmeyr GJ, Hannah M, Lawrie TA. Planned caesarean section for term breech delivery. Cochrane Database Syst Rev 2015;7:1–62. [12] Berhan Y, Haileamlak A. The risks of planned vaginal breech delivery versus planned caesarean section for term breech birth: a meta-analysis including observational studies. BJOG 2016;123:49–57. [13] Goffinet F, Carayol M, Foidart JM, Alexander S, Uzan S, Subtil D, et al. Is planned vaginal delivery for breech presentation at term still an option? Results of an observational prospective survey in France and Belgium. Am J Obstet Gynecol 2006;194:1002–11. [14] D’Ercole C. CNGOF – mises à jour en gyne’cologie et obste’trique et techniques chirurgicales. Paris: Diffusion Vigot-Paris 2011;195–218. [15] American College of Obstetricians and Gynecologists, Society for MaternalFetal Medicine. Obstetric care consensus no. 1: safe prevention of the primary cesarean delivery. Obstet Gynecol 2014;123:693–711. [16] Breton A, Gueudry P, Branger B, Le F, Thubert T, Arthuis C, et al. Comparison of obstetric prognosis of attempts of breech delivery: spontaneous labor versus induced labor. Gynecol Obstet Fertil Senol 2018;46:632–8.
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Please cite this article in press as: J. Chevreau, et al., Obstetrical and neonatal outcomes after successful external cephalic version relative to those after spontaneous cephalic presentations, J Gynecol Obstet Hum Reprod (2020), https://doi.org/10.1016/j.jogoh.2020.101693