Prediction of intrapartum Cesarean delivery for non-reassuring fetal status after a successful external cephalic version by a low pre-version pulsatility index of the fetal middle cerebral artery

Association between placental location and neonatal outcomes in manual fundal pressure-assisted vaginal deliveries: A retrospective single-center study in Japan

AIM

Manual fundal pressure (MFP) is still used to assist vaginal deliveries during the second stage of labor in predominantly lower-middle income countries; however, there is insufficient evidence on the risk factors in MFP-assisted vaginal deliveries for adverse neonatal outcomes. The aim of the present study was to investigate the association between placental location and neonatal outcomes in MFP-assisted vaginal deliveries.

METHODS

The present study was a single-center retrospective cohort study in patients with all MFP-assisted vaginal singleton deliveries from January 2016 to December 2020. Placental location was divided into two categories: posterior-lateral and anterior-fundal. The primary outcome was a neonatal adverse composite including umbilical artery blood pH <7.2, Apgar score <7 at 5 min, neonatal intensive care unit admission and neonatal resuscitation. We used multivariable logistic regression models to investigate the association between placental location and neonatal outcomes.

RESULTS

We extracted 522 MFP-assisted deliveries among 5053 vaginal deliveries. The proportion of posterior-lateral and anterior-fundal placentation was 239 (45.8%) and 283 (54.2%), respectively. The crude prevalence of neonatal composite outcome in the anterior-fundal group was significantly higher than that in the posterior-lateral group (39.6% vs. 28.9%; p = 0.013). Multivariable logistic regression analysis found that the prevalence of neonatal adverse outcome in the anterior-fundal group was significantly higher compared with the posterior-lateral group (adjusted odds ratio, 1.52; 95% confidence interval, 1.04-2.23).

CONCLUSION

Anterior-fundal placentation was significantly associated with an increased risk of neonatal adverse outcomes compared to posterior-lateral placentation in MFP-assisted vaginal deliveries.

Factors associated with intrapartum cesarean section after a successful external cephalic version

PURPOSE

External cephalic version (ECV) is an effective procedure to reduce the breech presentation at term reducing the chances of cesarean section. However even after successful ECV reports suggests the risk of having a cesarean section is high. The study analyzes the mode of delivery after a successful ECV and to identify the factors associated with intrapartum cesarean delivery compared to those with spontaneous cephalic presentation.

METHODS

This study was based on labor and delivery details, from the ECV registers, of 430 women who had successful ECV and they compared to those with spontaneous cephalic presentation. Primary outcome was delivery by cesarean section. Multiple logistic regression model was used to assess independent association of frisk factors associated with intrapartum cesarean section delivery by cesarean section and were presented as Odds Ratio (OR) and 95% confidence interval.

RESULTS

Cesarean section rates were similar among those who had a successful ECV and those with spontaneous cephalic presentation (22.3% vs 20.1%, p = 0.298). Women who had a successful ECV (OR = 1.5; (95%CI 1.13-1.98), maternal age (OR1.06-1.03-1.09), and previous delivery by cesarean section (OR = 5.16 (95%CI; 1.88-14.16) were found to associated with intrapartum cesarean section after adjusting for other factors.

CONCLUSION

Women who had a successful ECV had an increased risk of intrapartum cesarean section compared those women with spontaneous cephalic presentation. Further research should be performed to identify more risk factors, which could optimize intra-partum care to reduce the risk of cesarean section for women after 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.

The effect of transient fetal bradycardia and other heart rate changes during and after external cephalic version on perinatal outcomes

OBJECTIVES

To evaluate the effect of transient fetal bradycardia and other heart rate changes during and after external cephalic version (ECV) on perinatal outcomes. To determine factors associated with a higher risk of occurrence of transient fetal bradycardia during and after ECV.

STUDY DESIGN

Prospective study in 286 women after the 36th week of gestation with a fetus in breech presentation who have undergone an ECV attempt. The study analyses the incidence of transient fetal bradycardia during and immediately after ECV, the time interval to complete adjustment of fetal bradycardia, the factors associated with the occurrence of transient fetal bradycardia, cardiotocography (CTG) changes after ECV and perinatal outcomes. All the data were statistically analyzed.

RESULTS

The ECV was successful in 51 % (146/286). Transient fetal bradycardia occurred during and after ECV in 81 cases (28.3 %). A successful version was a factor significantly associated with fetal bradycardia (54; 37.0 % versus 27; 19.3 %; p < 0.01). Clinically significant hypotension of the mother was accompanied by transient fetal bradycardia in 12 cases (4.2 %). After the successful ECV there was no significant difference in the percentage of vaginal deliveries between subgroups with and without transient fetal bradycardia (85.2 % versus 83.7 %; p = 1.00). Nor in occurrence of acute fetal distress during labor (18.5 % versus 15.6 %; p = 0.65). In cases of a successful ECV transient CTG changes after ECV had no effect on the incidence of acute fetal distress during labor (23.5 % versus 15.7 %; p = 0.49).

CONCLUSIONS

Transient fetal bradycardia and other heart rate changes during and immediately after ECV was not associated with a higher incidence of acute fetal distress during labor and did not affect perinatal outcomes. Higher occurrence of transient bradycardia after ECV was associated only with successful ECV. Transient hypotension of the mother as one of the causes of transient fetal bradycardia during ECV should be considered.

Induction du travail après une version par manœuvres externes pour siège réussie : un sur-risque de césarienne?

OBJECTIVE

To assess the effect of successful external cephalic version (ECV) on the risk of caesarean section (CS) during attempted vaginal delivery after induction of labour.

METHODS

A unicentric matched retrospective observational case-control cohort study with exposed and unexposed groups. All pregnant women who had an induction of labour after a successful external cephalic version (sECV) between 1998 and 2016 were included. A total of 88 cases were compared with 176 controls (spontaneous cephalic presentation), matching for the year of delivery, parity, gestational age, indication and mode of induction of labour. The main outcome measure was the risk of caesarean. A univariate analysis and a multivariate logistic regression analysis were performed.

RESULTS

The caesarean section rate was significantly higher after sECV (22% versus 13.1%; p = 0.039) especially for postdate pregnancy (55% versus 8.2%; p <0.05). For the univariate analysis, age (31 years and 4 months versus 24 years and 6 months; p <0.01) and maximal speed of oxytocin infusion (72 ml/h versus 68 ml/h; p = 0.04) were higher in the case group. The multivariate analysis showed that the risk of caesarean section was significantly increased after an sECV (aOR 1.946; 95% CI 1.017-3.772) and after the use of prostaglandins for ripening (aOR 1.951; 95% CI 1.097-3.468), and decreased for multipara (aOR 0.208; 95% CI 0.114-0.377).

CONCLUSION

Women who have a successful ECV are at increased risk of caesarean section after subsequent induction of labour.

Fetal heart rate abnormalities during and after external cephalic version: Which fetuses are at risk and how are they delivered?

BACKGROUND

Fetal heart rate abnormalities (FHR) during and after external cephalic version (ECV) are relatively frequent. They may raise concern about fetal wellbeing. Only occasionally they may lead to an emergency cesarean section.

METHODS

Prospective cohort study in 980 women (> 34 weeks gestation) with a singleton fetus in breech presentation. During and after external cephalic version (ECV) FHR abnormalities were recorded. Obstetric variables and delivery outcome were evaluated. Primary outcome was to identify which fetuses are at risk for FHR abnormalities. Secondary outcome was to identify a possible relationship between FHR abnormalities during and after ECV and mode of delivery and fetal distress during subsequent labor.

RESULTS

The overall success rate of ECV was 60% and in 9% of the attempts there was an abnormal FHR pattern. In two cases FHR abnormalities after ECV led to an emergency CS. Estimated fetal weight per 100 g (OR 0.90, CI: 0.87-0.94) and longer duration of the ECV-procedure (OR 1.13, CI: 1.05-1.21) were factors significantly associated with the occurrence of FHR abnormalities. FHR abnormalities were not associated with the mode of delivery or the occurrence of fetal distress during subsequent labor.

CONCLUSIONS

FHR abnormalities during and after ECV are more frequent with lower estimated fetal weight and longer duration of the procedure. FHR abnormalities during and after ECV have no consequences for subsequent mode of delivery. They do not predict whether fetal distress will occur during labor.

TRIAL REGISTRATION

The Eindhoven Breech Intervention Study, NCT00516555 . Date of registration: August 13, 2007.

[Cord accident after external cephalic version: Reality or mostly myth?]

OBJECTIVES

To study the occurrence of cords accident (nuchal cords, prolapse, and braces) after external cephalic version according to its failure or success.

METHODS

Retrospective study between 1998-2015 comparing in the cord accident diagnosed at delivery (by midwife or doctors according to mode of delivery): Patients with attempt ECV: Group 1 cephalic presentation after successful ECV with trial of labor, and Group 2 failed ECV followed by elective cesarean or trial of labor. Patients with no attempt ECV Group 3 spontaneous cephalic presentation matching for delivery date, maternal age, parity, body mass index, and delivery history with group 1, Group 4 Breech presentation without attempt ECV with trial of labor.

RESULTS

A total of 776 women with breech presentation were included (198 in group 1, 446 in group 2, 396 in group 3 and 118 in group 4). The prevalence of cord accident did not differ according to ECV attempt (17.08 % versus 18.9 %), to cephalic presentation (group 1: 24.7 % versus group 3: 25 %) and to breech presentation (group 2: 16.9 % versus group 4: 17.2 %). The trial of labor after failed ECV did not increase the risk of cord accident when compared with elective cesarean (17.4 % versus 16 %). A prolapse cord was only observed after trial of labor, i.e. in groups 1, 2 and 4 without difference (respectively 1, 0.8 and 1.7 %). In each group, the rate of cesarean was not different according to the presence of nuchal cord.

CONCLUSION

Success or failed External cephalic version is not associated with an increased risk of cord accident.

Intrapartum intervention rates and perinatal outcomes following successful external cephalic version

OBJECTIVE

To determine intrapartum and perinatal outcomes following successful external cephalic version for breech presentation at term.

STUDY DESIGN

This was a retrospective cohort study of outcomes following successful external cephalic version in 411 women at an Australian tertiary maternity unit between November 2008 and March 2015. The study cohort was compared with a control group of 1236 women with cephalic presentation who underwent spontaneous labor. Intrapartum intervention rates and adverse neonatal outcomes were compared between both groups.

RESULTS

The success rate of external cephalic version (ECV) was 66.4%. The spontaneous vaginal delivery rate in the study cohort was 59.4% (224/411) vs 72.8% (900/1236) in the control cohort (P<0.001). Intrapartum intervention rates (emergency cesarean section (CS) and instrumental delivery) were higher in the ECV group (38% vs 27.2%, P<0.001). Rates of emergency CS for non-reassuring fetal status (9.5%, 39/411 vs 4.4%, 54/1236, P⩽0.001) and failure to progress (13.4%, 55/411 vs 4.1%, 51/1236, P<0.001) were higher in the study cohort. Neonatal outcomes were worse in the study cohort-Apgar score <7 at 5 min (2.2%, 9/411 vs 0.6%, 8/1236, P<0.001) and abnormal cord gases (8.5%, 35/411 vs 0.2%, 3/1236, P<0.001). Rates for resuscitation at birth and admission to the neonatal intensive care unit were higher in the study cohort (6.1% vs 4.1% and 1.9% vs 1.1%, respectively) but these were not statistically significant.

CONCLUSION

Labor following successful ECV is more likely to result in increased intrapartum intervention rates and poorer neonatal outcomes.

Expert review--identification of intra-partum fetal compromise

Whilst most cases of cerebral palsy occur as a consequence of an ante-natal insult, a significant proportion, particularly in the term fetus, are attributable to intra-partum hypoxia. Intra-partum monitoring using continuous fetal heart rate assessment has led to an increased incidence of operative delivery without a concurrent reduction in the incidence of cerebral palsy. Despite this, birth asphyxia remains the strongest and most consistent risk factor for cerebral palsy in term infants. This review evaluates current intra-partum monitoring techniques as well as alternative approaches aimed at better identification of the fetus at risk of compromise in labour.

Outcome of induction of labour using maternal characteristics, ultrasound assessment and biochemical state of the cervix

OBJECTIVE

To assess pre-induction sonographic, digital examination and biochemical changes in the cervix to predict induction outcome.

METHODS

Transvaginal and abdominal scans were performed in 460 women at 37-41 weeks of gestation to determine cervical length (CL), posterior cervical angle (PCA) and foetal occipital position. The Bishop Score (BS) and the absence/presence of phosphorylated form of insulin-like growth factor-binding protein-1 (phIGFBP-1) in cervical secretions were assessed. Independent parameters significantly associated with a vaginal delivery were identified.

RESULTS

A total of 340 (73.9%) women achieved a vaginal delivery following induction. Multivariate analysis indicated that significant independent predictors of vaginal delivery were CL (adjusted odds ratio [AOR]: 0.59, 95% confidence interval [CI]: 0.45-0.79), PCA (AOR: 1.89, 95% CI: 1.09-3.28) and multiparae (AOR: 10.02, 95% CI: 5.10-19.69). For a specificity of 75%, the sensitivity for prediction of vaginal delivery using the BS, the CL and the multivariate model using the identified significant independent predictors were 37.1, 46.8 and 68%, respectively.

CONCLUSION

The combination of sonographic assessment of the cervix and maternal characteristics was superior to the either BS or CL alone in the prediction of the induction outcome. Inclusion of the absence/presence of phIGFBP-1 did not further improve induction outcome.

Clinical factors to predict the outcome of external cephalic version: a metaanalysis

OBJECTIVE

The objective of the study was to systematically review the medical literature reporting on potential clinical prognosticators for the outcome of external cephalic version (ECV).

STUDY DESIGN

Medline, EMBASE, and Cochrane Central Register of Controlled Trials were searched. Studies reporting on potential clinical prognosticators and ECV success rates that allowed construction of a 2 x 2 table were selected.

RESULTS

We detected 53 primary articles reporting on 10,149 women. Multiparity (P >/= 1.00; odds ratio [OR], 2.5; 95% confidence interval [CI], 2.3-2.8), nonengagement of the breech (OR, 9.4; 95% CI, 6.3-14), a relaxed uterus (OR, 18; 95% CI, 12-29), a palpable fetal head (OR, 6.3; 95% CI, 4.3-9.2), and maternal weight less than 65 kg (OR, 1.8; 95% CI, 1.2-2.6) were predictors for successful external cephalic version.

CONCLUSION

Success of an ECV attempt is associated with clinical factors. This should be taken into account in the counseling of women prior to an ECV attempt.