Randomized, double blind, placebo controlled comparison of ritodrine and hexoprenaline for tocolysis prior to external cephalic version at term

Prediction Models for Successful External Cephalic Version: An Updated Systematic Review

OBJECTIVE

 To review the decision aids currently available or being developed to predict a patient's odds that their external cephalic version (ECV) will be successful.

STUDY DESIGN

 We searched PubMed/MEDLINE, Cochrane Central, and ClinicalTrials.gov from 2015 to 2022. Articles from a pre-2015 systematic review were also included. We selected English-language articles describing or evaluating models (prediction rules) designed to predict an outcome of ECV for an individual patient. Acceptable model outcomes included cephalic presentation after the ECV attempt and whether the ECV ultimately resulted in a vaginal delivery. Two authors independently performed article selection following PRISMA 2020 guidelines. Since 2015, 380 unique records underwent title and abstract screening, and 49 reports underwent full-text review. Ultimately, 17 new articles and 8 from the prior review were included. Of the 25 articles, 22 proposed one to two models each for a total of 25 models, while the remaining 3 articles validated prior models without proposing new ones.

RESULTS

 Of the 17 new articles, 10 were low, 6 moderate, and 1 high risk of bias. Almost all articles were from Europe (11/25) or Asia (10/25); only one study in the last 20 years was from the United States. The models found had diverse presentations including score charts, decision trees (flowcharts), and equations. The majority (13/25) had no form of validation and only 5/25 reached external validation. Only the Newman-Peacock model (United States, 1993) was repeatedly externally validated (Pakistan, 2012 and Portugal, 2018). Most models (14/25) were published in the last 5 years. In general, newer models were designed more robustly, used larger sample sizes, and were more mathematically rigorous. Thus, although they await further validation, there is great potential for these models to be more predictive than the Newman-Peacock model.

CONCLUSION

 Only the Newman-Peacock model is ready for regular clinical use. Many newer models are promising but require further validation.

KEY POINTS

· 25 ECV prediction models have been published; 14 were in the last 5 years.. · The Newman-Peacock model is currently the only one with sufficient validation for clinical use.. · Many newer models appear to perform better but await further validation..

[Breech Presentation: CNGOF Guidelines for Clinical Practice - External Cephalic Version and other Interventions to turn Breech Babies to Cephalic Presentation]

OBJECTIVES

To provide guidelines regarding efficiency and safety of external cephalic version (ECV) attempt and alternatives methods to turn breech babies to cephalic presentation.

METHODS

MedLine and Cochrane Library databases search in French and English and review of the main foreign guidelines between 1980 and 2019.

RESULTS

ECV is associated with a decreasing rate of breech presentation at birth (LE2), and potentially with a lower rate of cesarean section (LE3) without an increase of severe maternal (LE3) and perinatal morbidity (LE3). It is therefore recommended to inform women with a breech presentation at term that ECV should be attempt (Professional consensus). ECV attempt should be performed with immediate access to an operating room for emergency cesarean (Professional consensus). The ECV attempt before 37 weeks, compared to ECV attempt after 37 weeks, increases the rate of cephalic presentation at birth (LE2) but with a small increase risk of moderate prematurity (LE2). ECV attempt should be performed from 36SA (Professional consensus). The main factors associated with successful ECV attempt are multiparity (LE3) and no maternal obesity (LE3). Parenteral tocolysis (β mimetic or atosiban), for ECV attempt at term is associated with a higher success rate (LE2), higher rate of achieved cephalic presentation in labor (LE2) and a lower cesarean section rate (LE2). It is recommended to use parenteral tocolysis for ECV attempt at term in order to increase its success rate (grade B). The ECV attempt is associated with an increase in transient FHR abnormalities (LE3), it is therefore recommended that cardiotocography should be performed prior and during 30minutes after the procedure (Professional consensus). There is no argument for recommending the practice of delayed cardiotocography after ECV attempt (Professional consensus). The risk of significant positivity (>30mL) of the Kleihauer test after ECV attempt is low (<0.1%) (LE3), it is not recommended to systematically perform a Kleihauer test after ECV attempt (professional consensus). In case of RH-1 negative women, it is recommended to ensure systematic RH-1 prophylaxis (Professional consensus). In case of breech presentation at term, acupuncture, moxibustion and postural methods are not effective in reducing breech presentation at birth (LE2), and are therefore not recommended (Grade B).

CONCLUSION

According to the clear benefits and the low risks of ECV attempt, all women with a breech presentation at term should be informed that ECV should be attempted to decrease breech presentation at birth and cesarean section.

Interventions for helping to turn term breech babies to head first presentation when using external cephalic version

BACKGROUND

Breech presentation is associated with increased complications. Turning a breech baby to head first presentation using external cephalic version (ECV) attempts to reduce the chances of breech presentation at birth so as to avoid the adverse effects of breech vaginal birth or caesarean section. Interventions such as tocolytic drugs and other methods have been used in an attempt to facilitate ECV.

OBJECTIVES

To assess, from the best evidence available, the effects of interventions such as tocolysis, acoustic stimulation for midline spine position, regional analgesia (epidural or spinal), transabdominal amnioinfusion, systemic opioids and hypnosis, or the use of abdominal lubricants, on ECV at term for successful version, presentation at birth, method of birth and perinatal and maternal morbidity and mortality.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2014) and the reference lists of identified studies.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing the above interventions with no intervention or other methods to facilitate ECV at term.

DATA COLLECTION AND ANALYSIS

We assessed eligibility and trial quality. Two review authors independently assessed for inclusion all potential studies identified as a result of the search strategy and independently extracted the data using a specially designed data extraction form.

MAIN RESULTS

We included 28 studies, providing data on 2786 women. We used the random-effects model for pooling data because of clinical heterogeneity between studies. A number of trial reports gave insufficient information to allow clear assessment of risk of bias. We used GradePro software to carry out formal assessments of quality of the evidence for beta stimulants versus placebo and regional analgesia with tocolysis versus tocolysis alone.Tocolytic parenteral beta stimulants were effective in increasing cephalic presentations in labour (average risk ratio (RR) 1.68, 95% confidence interval (CI) 1.14 to 2.48, five studies, 459 women, low-quality evidence) and in reducing the number of caesarean sections (average RR 0.77, 95% CI 0.67 to 0.88, six studies, 742 women, moderate-quality evidence). Failure to achieve a cephalic vaginal birth was less likely for women receiving a parenteral beta stimulant (average RR 0.75, 95% CI 0.60 to 0.92, four studies, 399 women, moderate-quality evidence). No clear differences in fetal bradycardias were identified, although this was reported for only one study, which was underpowered for assessing this outcome. Failed external cephalic version was reported in nine studies (900 women), and women receiving parenteral beta stimulants were less likely to have failure compared with controls (average RR 0.70, 95% CI 0.60 to 0.82, moderate-quality evidence). Perinatal mortality and serious morbidity were not reported. Sensitivity analysis by study quality was consistent with overall findings.For other classes of tocolytic drugs (calcium channel blockers and nitric oxide donors), evidence was insufficient to permit conclusions; outcomes were reported for only one or two studies, which were underpowered to demonstrate differences between treatment and control groups. Little evidence was found regarding adverse effects, although nitric oxide donors were associated with increased risk of headache. Data comparing different tocolytic drugs were insufficient.Regional analgesia in combination with a tocolytic was more effective than the tocolytic alone for increasing successful versions (assessed by the rate of failed ECVs; average RR 0.61, 95% CI 0.43 to 0.86, five studies, 409 women, moderate-quality evidence), and no difference was identified in cephalic presentation in labour (average RR 1.63, 95% CI 0.75 to 3.53, three studies, 279 women, very low-quality evidence), caesarean sections (average RR 0.74, 95% CI 0.40 to 1.37, three studies, 279 women, very low-quality evidence) nor fetal bradycardia (average RR 1.48, 95% CI 0.62 to 3.57, two studies, 210 women, low-quality evidence), although studies were underpowered for assessing these outcomes. Studies did not report on failure to achieve a cephalic vaginal birth (breech vaginal deliveries plus caesarean sections) nor on perinatal mortality or serious infant morbidity.Data were insufficient on the use of regional analgesia without tocolysis, vibroacoustic stimulation, amnioinfusion, systemic opioids and hypnosis, and on the use of talcum powder or gel to assist external cephalic version, to permit conclusions about their effectiveness and safety.

AUTHORS' CONCLUSIONS

Parenteral beta stimulants were effective in facilitating successful ECV, increasing cephalic presentation in labour and reducing the caesarean section rate, but data on adverse effects were insufficient. Data on calcium channel blockers and nitric acid donors were insufficient to provide good evidence.The scope for further research is clear. Possible benefits of tocolysis in reducing the force required for successful version and possible risks of side effects need to be addressed further. Further trials are needed to compare the effectiveness of routine versus selective use of tocolysis and the role of regional analgesia, fetal acoustic stimulation, amnioinfusion and abdominal lubricants, and the effects of hypnosis, in facilitating ECV. Although randomised trials of nitric oxide donors are small, the results are sufficiently negative to discourage further trials. Intervention fidelity for ECV can be enhanced by standardisation of the techniques and processes used for clinical manipulation of the fetus in the abdominal cavity and ought to be the subject of further research.

Interventions for helping to turn term breech babies to head first presentation when using external cephalic version

BACKGROUND

Breech presentation is associated with increased complications. Turning a breech baby to head first presentation using external cephalic version (ECV) attempts to reduce the chances of breech presentation at birth, and reduce the adverse effects of breech vaginal birth or caesarean section. Tocolytic drugs and other methods have been used in an attempt to facilitate ECV.

OBJECTIVES

To assess interventions such as tocolysis, fetal acoustic stimulation, regional analgesia, transabdominal amnioinfusion or systemic opioids on ECV for a breech baby at term.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2011) and the reference lists of identified studies.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing the above interventions with no intervention or other methods to facilitate ECV at term.

DATA COLLECTION AND ANALYSIS

We assessed eligibility and trial quality. Two review authors independently assessed for inclusion all potential studies identified as a result of the search strategy and independently extracted the data using a designed data extraction form.

MAIN RESULTS

We included 25 studies, providing data on 2548 women. We used the random-effects model for pooling data due to clinical heterogeneity in the included studies in the various comparisons. The overall quality of the evidence was reasonable, but a number of assessments had insufficient data to provide an answer with any degree of assurance.Tocolytic drugs, in particular betastimulants, were effective in increasing cephalic presentations in labour (average risk ratio (RR) 1.38, 95% confidence interval (CI) 1.03 to 1.85, eight studies, 993 women) and in reducing the number of caesarean sections (average RR 0.82, 95% CI 0.71 to 0.94, eight studies, 1177 women). No differences were identified in fetal bradycardias (average RR 0.95, 95% CI 0.48 to 1.89, three studies, 467 women) although the review is underpowered for assessing this outcome. We identified no difference in success, cephalic presentation in labour and caesarean sections between nulliparous and multiparous women. There were insufficient data comparing different groups of tocolytic drugs. Sensitivity analyses by study quality agreed with the overall findings.Regional analgesia in combination with a tocolytic was more effective than the tocolytic alone in terms of increasing successful versions (assessed by the rate of failed ECVs, average RR 0.67, 95% CI 0.51 to 0.89, six studies, 550 women) but there was no difference identified in cephalic presentation in labour (average RR 1.63, 95% CI 0.75 to 3.53, three studies, 279 women) nor in caesarean sections (average RR 0.74, 95% CI 0.40 to 1.37, three studies, 279 women) or fetal bradycardia (average RR 1.48, 95% CI 0.62 to 3.57, two studies, 210 women).There were insufficient data on the use of vibroacoustic stimulation, amnioinfusion or systemic opioids.

AUTHORS' CONCLUSIONS

Betastimulants, to facilitate ECV, increased cephalic presentation in labour and birth, and reduced the caesarean section rate in both nulliparous and multiparous women, but there were insufficient data on adverse effects. Calcium channel blockers and nitric acid donors had insufficient data to provide good evidence. At present we recommend betamimetics for facilitating ECV.There is scope for further research. The possible benefits of tocolysis to reduce the force required for successful version and the possible risks of maternal cardiovascular side effects, need to be addressed further. Further trials are needed to compare the effectiveness of routine versus selective use of tocolysis, the role of regional analgesia, fetal acoustic stimulation, amnioinfusion and the effect of intravenous or oral hydration prior to ECV.Although randomised trials of nitroglycerine are small, the results are sufficiently negative to discourage further trials.

Randomized comparison of intravenous nitroglycerin and subcutaneous terbutaline for external cephalic version under tocolysis

OBJECTIVE

The purpose of this study was to compare the efficacy and safety of intravenous nitroglycerin with that of subcutaneous terbutaline as a tocolytic agent for external cephalic version at term.

STUDY DESIGN

We performed a prospective randomized trial. Patients between 37 and 42 weeks of gestation were assigned randomly to receive either 200 microg of intravenous nitroglycerin therapy or 0.25 mg of subcutaneous terbutaline therapy for tocolysis during external cephalic version. The rate of successful external cephalic version and side effects were compared between groups.

RESULTS

Of 59 randomly assigned patients, 30 patients received intravenous nitroglycerin, and 29 patients received subcutaneous terbutaline. The overall success rate of external cephalic version in the study was 39%. The rate of successful external cephalic version was significantly higher in the terbutaline group (55% vs 23%; P = .01). The incidence of palpitations was significantly higher in patients who received terbutaline therapy (17.2% vs 0%; P = .02), as was the mean maternal heart rate at multiple time periods.

CONCLUSION

Compared with intravenous nitroglycerin, subcutaneous terbutaline was associated with a significantly higher rate of successful external cephalic version at term.

Interventions to help external cephalic version for breech presentation at term

BACKGROUND

Breech presentation places a fetus at increased risk. The outcome for the baby is improved by planned caesarean section compared with planned vaginal delivery. External cephalic version attempts to reduce the chances of breech presentation at birth, but is not always successful. Tocolytic drugs to relax the uterus as well as other methods have been used in an attempt to facilitate external cephalic version at term.

OBJECTIVES

To assess the effects of routine tocolysis, fetal acoustic stimulation, epidural or spinal analgesia and transabdominal amnioinfusion for external cephalic version at term on successful version and measures of pregnancy outcome.

SEARCH STRATEGY

The Cochrane Pregnancy and Childbirth Group trials register (September 2003) and the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3, 2003) were searched.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing routine versus selective or no tocolysis; fetal acoustic stimulation in midline fetal spine positions versus dummy or no stimulation; epidural or spinal analgesia versus no regional analgesia; or transabdominal amnioinfusion versus no amnioinfusion for external cephalic version at term.

DATA COLLECTION AND ANALYSIS

The reviewer assessed eligibility and trial quality.

MAIN RESULTS

In six trials, routine tocolysis with beta-stimulants was associated with fewer failures of external cephalic version (relative risk (RR) 0.74, 95% confidence interval (CI) 0.64 to 0.87). The reduction in non-cephalic presentations at birth was not statistically significant. Caesarean sections were reduced (RR 0.85, 95% CI 0.72 to 0.99). In four small trials, sublingual nitroglycerine used as a tocolytic was associated with significant side-effects, and was not found to be effective. Fetal acoustic stimulation in midline fetal spine positions was associated with fewer failures of external cephalic version at term (RR 0.17, 95% CI 0.05 to 0.60). With epidural or spinal analgesia, external cephalic version failure, non-cephalic births and caesarean sections were reduced in two trials but not the other. The overall differences were not statistically significant. No randomised trials of transabdominal amnioinfusion for external cephalic version at term were located.

REVIEWER'S CONCLUSIONS

Routine tocolysis appears to reduce the failure rate of external cephalic version at term. There is not enough evidence to evaluate the use of fetal acoustic stimulation in midline fetal spine positions, nor of epidural or spinal analgesia. Large volume intravenous preloading may have contributed to the effectiveness demonstrated in two of the latter trials.

Sublingual nitroglycerin versus intravenous ritodrine as tocolytic for external cephalic version: a double-blinded randomized trial

OBJECTIVE

The purpose of this study was to compare the efficacy of sublingual nitroglycerin with that of intravenous ritodrine as a tocolytic agent for external cephalic version in nulliparous women.

STUDY DESIGN

We performed a double-blinded, randomized trial. Nulliparous patients, between 36 and 40 weeks of gestation, were assigned randomly to receive either (1) an intravenous infusion of ritodrine (111 microg/min) for 20 minutes, followed by two puffs of sublingual placebo or (2) an intravenous infusion of sodium chloride 0.9% (placebo) for 20 minutes, followed by two puffs of sublingual 0.4 mg of nitroglycerin. Three minutes after the administration of the sublingual spray, an external cephalic version was attempted. The rate of successful external cephalic version and side effects was compared between groups.

RESULTS

Of 74 randomly assigned patients, 38 patients received intravenous ritodrine, and 36 patients received sublingual nitroglycerin. Although not statistically significant, the rate of the successful external cephalic version was higher in the ritodrine group compared with the nitroglycerin group (45% vs 25%, P =.075). The rate of headaches was higher in patients who received nitroglycerin (28% vs 8%, P =.02). Mean blood pressure and maternal heart rate were lower in the nitroglycerin group 10 minutes after the administration of the medication. However, there was no significant difference in the rate of palpitations, hypotension, or fetal bradycardia between the two groups.

CONCLUSION

When compared with intravenous ritodrine, sublingual nitroglycerin was associated with a higher rate of headache, lower blood pressure, and a trend toward a lower rate of successful external cephalic version.

Sublingual nitroglycerine as a tocolytic in external cephalic version: a comparative study

OBJECTIVE

To study the effect of sublingual nitroglycerine as a tocolytic on the success rate of external cephalic version (ECV) in nulliparous and parous women.

METHODS

A retrospective case-controlled study of all ECV cases from February 1996 to February 2000 in a single centre. The rates of successful ECV were compared between women who had their ECV before February 1998 (control group), those who had their ECV after February 1998 and received 0.8 mg sublingual nitroglycerine spray as a tocolytic agent, and those who had their ECV after February 1998 and received no tocolytic agents. Nulliparous and parous women were studied separately. Data were collected for parity, gestational age, maternal age, placental localization, and side effects. Chi-square and Kruskal-Wallis tests were performed for statistical comparison.

RESULTS

Of 150 women who had their ECV after February 1998, 120 (80%) received sublingual nitroglycerine (group 1: cases using 0.8 mg sublingual nitroglycerine spray as a tocolytic agent) and were compared to the 30 patients who did not receive sublingual nitroglycerine or other tocolytics after February 1998 (group 2) and to 137 patients who had their ECV before February 1998 (control group). Of the women who received sublingual nitroglycerine, 5 (4%) had hypotension and 7 (6%) had headaches and/or nausea. The rate of successful ECV was 27% in group 1 versus 30% in group 2 (p = 0.86) versus 28% in the control group (p = 0.88) for nulliparous patients, and 67% versus 80% (p = 0.30) versus 51% (p = 0.09) respectively for parous women. However, the success rate was increased overall in parous women after the introduction of nitroglycerine as a tocolytic for ECV in February 1998 (71% vs. 51%, p = 0.02).

CONCLUSION

Although the success rate of ECV has increased in recent years, the use of sublingual nitroglycerine as a tocolytic was not associated with this higher success rate. A randomized, controlled trial is needed.

Interventions to help external cephalic version for breech presentation at term

BACKGROUND

Breech presentation places a fetus at increased risk. The outcome for the baby is improved by planned caesarean section compared with planned vaginal delivery. External cephalic version attempt reduces the chance of breech presentation at birth, but is not always successful. Tocolytic drugs to relax the uterus as well as other methods have been also used in an attempt to facilitate external cephalic version at term.

OBJECTIVES

The objective of this review is to assess the effects of routine tocolysis, fetal acoustic stimulation, epidural or spinal analgesia and transabdominal amnioinfusion for external cephalic version at term on successful version and measures of pregnancy outcome.

SEARCH STRATEGY

The Cochrane Pregnancy and Childbirth Group Trials Register (searched December 2001) and the Cochrane Controlled Trials Register (The Cochrane Library, Issue 4, 2001) were searched.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing routine versus selective or no tocolysis; fetal acoustic stimulation in midline fetal spine positions versus dummy or no stimulation; epidural or spinal analgesia versus no regional analgesia; or transabdominal amnioinfusion versus no amnioinfusion for external cephalic version at term.

DATA COLLECTION AND ANALYSIS

Eligibility and trial quality were assessed by the reviewer.

MAIN RESULTS

In six trials, routine tocolysis was associated with fewer failures of external cephalic version (relative risk 0.74, 95% confidence interval 0.64 to 0.87). The reduction in non-cephalic presentations at birth was not statistically significant. Caesarean sections were reduced (relative risk 0.85, 95% confidence interval 0.72 to 0.99). Fetal acoustic stimulation in midline fetal spine positions was associated with fewer failures of external cephalic version at term (relative risk 0.17, 95% confidence interval 0.05 to 0.60). With epidural or spinal analgesia, external cephalic version failure, non-cephalic births and caesarean sections were reduced in two trials but not the other. The overall differences were not statistically significant. No randomised trials of transabdominal amnioinfusion for external cephalic version at term were located.

REVIEWER'S CONCLUSIONS

Routine tocolysis appears to reduce the failure rate of external cephalic version at term. Although promising, there is not enough evidence to evaluate the use of fetal acoustic stimulation in midline fetal spine positions, nor of epidural or spinal analgesia. Large volume intravenous preloading may have contributed to the effectiveness demonstrated in two of the latter trials. No randomised trials of transabdominal amnioinfusion for external cephalic version at term were found.

Outcome of labour after successful external cephalic version at term complicated by isolated transient fetal bradycardia

OBJECTIVES

To investigate factors associated with the occurrence of transient fetal bradycardia after external cephalic version, and labour outcome after isolated transient fetal bradycardia.

DESIGN

Cohort study.

SETTING

Teaching hospital with a policy of offering external cephalic version for breech presentation at or beyond 36 weeks of gestation.

POPULATION

Four hundred and twenty-nine external cephalic versions performed over a 5-year period.

METHODS

Between group differences were compared with the unpaired t test or the chi2 test. Logistic regression analysis was performed to exclude confounding effects.

MAIN OUTCOME MEASURES

Incidence of caesarean section for fetal distress.

RESULTS

Transient fetal bradycardia occurred in 8.4% of external cephalic versions, and was associated with a successful version (OR 16.45, P < 0.001), a difficult procedure (OR 3.70, P = 0.001), and nulliparity (OR 2.83, P = 0.007). The incidence of intrapartum caesarean section for fetal distress was 16.7% in pregnancies with transient fetal bradycardia, compared with 7.9% in those without (OR 2.34, 95% CI 0.81, 6.71).

CONCLUSIONS

Transient fetal bradycardia after external cephalic version may be associated with a higher risk of intrapartum caesarean section for fetal distress.

External cephalic version with epidural anaesthesia after failure of a first trial with beta-mimetics

OBJECTIVE

To assess the efficacy, tolerance, and cost of external version under epidural anaesthesia and beta-mimetic tocolysis after the failure of an initial attempt with tocolysis alone.

DESIGN

Prospective open study.

PARTICIPANTS

Sixty-eight women with breech presentation at around 36 weeks of gestation and an attempted external cephalic version under salbutamol that failed, who consented to try a second attempt under epidural anaesthesia.

RESULTS

The overall success rate under epidural anaesthesia was 39.7% (27/68), and complications occurred in two cases. The total cost of attempting external version was higher than the cost of expectant management.

CONCLUSIONS

The efficacy of external cephalic version under epidural reduces the rate of caesarean sections associated with breech presentation, but its relative safety remains in question. Moreover, our economic analysis discourages the hope of lowered costs suggested by earlier reports that this technique is more expensive than expectant management, except in institutions with a policy of systematic caesarean sections when version fails.

The implementation of external cephalic version at term for singleton breech presentation--how can we further increase its impact?

The overall incidence of breech presentation at delivery remained at 2 to 3% in a unit where external cephalic version (ECV) was the preferred treatment option for term singleton breech presentation. The objective of this study was to investigate which factors accounted for this high residual incidence, so that the impact of ECV could be further increased. All breech deliveries and ECVs over a 1-year period in a teaching hospital are reviewed. The incidence of term singleton breech delivery was 1.96% among 7,702 total deliveries. There were 115 patients counselled for ECV, of which 15.7% declined the offer and 4.1% went into labour before their scheduled ECV. Among the 93 ECVs performed, 74 were successful and 56 delivered vaginally in cephalic presentation. ECV was not performed in 131 cases. The major reasons were patients' refusal (13.7%), breech first diagnosed in labour or after rupture of membranes (44.3%), oligohydramnios or growth retardation (9.9%) and previous Caesarean section (8.4%). Only 5 patients were not counselled for ECV in the absence of contraindications. The practice of ECV reduced the overall Caesarean section rate by 0.65%, or 4.3% of the total number of Caesarean sections. In conclusion, ECV at term definitely reduces the Caesarean section rate. However, it is unlikely that the overall Caesarean section rate could be reduced by more than 1% even with 100% uptake of ECV unless the use of ECV is to be extended to those with prior Caesarean section, ruptured membranes, oligohydramnios, growth retardation or those who are in labour.

Introducing external cephalic version at 36 weeks or more in a district general hospital: a review and an audit

OBJECTIVE

To audit the effect of introducing external cephalic version at > or = 36 weeks on breech delivery rates and modes, and to assess factors that affect external cephalic version success rates.

DESIGN

A prospective unblinded study over 12 months of factors affecting external cephalic version success. A retrospective review of breech deliveries for 12 months before introducing external cephalic version and the first 12 months of practising external cephalic versions.

SETTING

Royal United Hospital, Bath.

POPULATION

One hundred and three women (> or = 36 weeks) with breech presentation booked for external cephalic version, and 324 women with a singleton breech presentation at delivery between November 1992 and October 1994.

METHODS

External cephalic version attempted on 89 women. Tocolysis was used on 41 of these women.

MAIN OUTCOME MEASURES

External cephalic version success rate. Breech presentation rates (suitable for external cephalic version) at delivery. Delivery mode rates for breeches.

RESULTS

External cephalic version was successful in 39% of women. The breech presentation rate (external cephalic version suitable) at delivery fell from 2.7% to 2.4% of all deliveries. The vaginal breech delivery rate fell from 0.98% to 0.51%. The caesarean section rate was 63% for breeches (external cephalic version suitable) before external cephalic version introduction, and 47% among women who had an attempted external cephalic version.

CONCLUSIONS

Attempted external cephalic version reduces the woman's risk of vaginal breech delivery and caesarean section. It provides individual women with a third management option and the possibility of avoiding a vaginal breech delivery or a caesarean section. To avoid one caesarean section takes 5.9 attempted external cephalic versions. This approach is expensive in operator time. Operator, placental site, position of fetal back and amniotic fluid index had a significant effect on the success of external cephalic version.

Predictors of successful external cephalic version at term: a prospective study

OBJECTIVE

To investigate clinical and ultrasonographic predictors of outcome of external cephalic version at term.

DESIGN

Prospective observational study.

SETTING

University obstetric unit.

POPULATION

All external cephalic versions performed over two years (n = 243).

METHODS

Nineteen different clinical and ultrasonographic variables were recorded before each procedure. The ability of each of the 19 variables to predict the success or failure of external cephalic version was assessed by univariate analysis. The study population was then divided into two subgroups of 129 and 114 patients by random allocation using computer generated numbers. Logistic regression was performed in each subgroup to assess the relative importance and independence of the important variables. The derived regression models were then applied to the other subgroup of patients to assess accuracy and reproducibility.

RESULTS

The overall success rate of the procedure was 69.5%. Both regression models identified the same three variables as independent predictors of failed versions: 1. presenting part engaged; 2. difficult to palpate the fetal head, and 3. a tense uterus on palpation. The two models correctly predicted 75.2% and 84.2% of outcomes in the other subgroup. If uterine tone, which was assessed after administration of tocolytic, was excluded from the analysis, the other two factors remained in the models, with the addition of nulliparity as a significant predictor of failed external cephalic version. The chance of success of external cephalic version in the original 243 women was found to be < 20% if two of these variables were present, 0% if all three were present, and 94% if none were present.

CONCLUSIONS

The outcome of external cephalic version can be predicted by easily available clinical parameters.

Pregnancy outcome after successful external cephalic version for breech presentation at term

OBJECTIVE

Our purpose was to review the outcome of pregnancies after external cephalic version at term, in particular the incidence and indications of intrapartum cesarean section after successful external cephalic version.

STUDY DESIGN

A prospective study was performed of 241 term pregnancies that had a total of 243 external cephalic versions. Each case with successful external cephalic version was matched to two control cases with cephalic presentation to compare pregnancy outcome.

RESULTS

External cephalic version was successful in 169 attempts (69.5%), of which 7 (4.1%) reverted to breech presentation. There was one case of abruptio placentae and eight cases (3.3%) of transient fetal bradycardia after the procedure. Among those who had a successful external cephalic version, the incidence of intrapartum cesarean section was 16.9%, which was 2.25 times higher than that of the control group (p < 0.005). This large number of abdominal deliveries was due to a significantly higher incidence of fetal distress and dystocic labor. The incidence of augmentation of labor was also significantly higher in the study group (37.7% vs 27.6%, p < 0.05).

CONCLUSION

Pregnancies after a successful external cephalic version at term are not the same as those with cephalic presentation. They are at higher risk of both dystocic labor and fetal distress and therefore require close intrapartum monitoring.

Outcome of external cephalic version: our experience

The aim is to assess the outcome of external cephalic version (ECV) for term breech in our clinical setting and the factors involved. Patients with no contraindications and who consented to ECV were recruited into this prospective study. Terbutalin infusion was used. There were 42 ECV attempts of which 21 (50%) were successful. Seventeen of the patients with successful ECV delivered vaginally and 4 had cesarean section for various indications. Only 5 of the 21 unsuccessful ECV delivered vaginally. Thirteen had elective cesarean section and 2 had emergency cesarean during trial of breech. One patient from the unsuccessful ECV group was lost to follow-up. There were 31 (74%) primipara. The birth weight of the babies was not a significant factor in the outcome of ECV. The type of breech and parity did influence the success rate. External cephalic version should be included in the routine management of our breech presentation.

Fetomaternal haemorrhage after external cephalic version at term

The incidence of fetomaternal haemorrhage after external cephalic version was 1.8% in 167 patients. The occurrence of this complication was not found to be associated with difficult or unsuccessful version, or with any adverse perinatal outcome. We conclude that routine assessment of fetomaternal haemorrhage after external version is not necessary, except in rhesus negative women to detect the 2% in whom the routine dose of 500 iu (100 micrograms) of anti-D immunoglobulin is inadequate.