Risk factors for unsuccessful vaginal birth after caesarean at full dilatation

OBJECTIVES

The purpose of this study was to determine the risk factors for caesarean sections in the second stage of labour after a previous caesarean section among women who underwent trial of labour (TOL).

MATERIAL AND METHODS

From a total of 639 women who experienced one caesarean section, 456 women were qualified for TOL. From this group, 105 women were subjected to a caesarean section in the first stage of labour and another 351 women reached the second stage of labour. From the latter group, 309 women delivered naturally and 42 were subjected to a caesarean section.

RESULTS

Risk factors for the necessity of performing a caesarean section in the second stage of labour after a previous caesarean section was the weight gain during pregnancy (OR = 1.07), the height of fundus uteri (OR = 1.25) before delivery, and the estimated foetal weight (OR = 1.01), a past delivery of a child with a birth weight exceeding 4.000 g (OR = 2.14), the presence of pre-gestational diabetes (OR = 15.4) and gestational diabetes (OR = 2.22), necessity of applying a delivery induction (OR = 2.52), stimulation of uterine activity during delivery (OR = 2.43) and application of epidural analgesia (OR = 4.04). A factor reducing the risk of a caesarean section in the second stage was a vaginal delivery in a woman's history (OR = 0.21).

CONCLUSIONS

Women should be encouraged to deliver naturally after a previous caesarean section, especially when their history includes a vaginal delivery and if there is no need for labour induction.

Labour Management in Trial of Labour After Cesarean Delivery (TOLAC): A Gap Analysis and Quality Improvement Initiative

OBJECTIVE

This quality improvement (QI) initiative was designed to identify gaps between evidence-based or hospital recommendations for trial of labour after cesarean delivery (TOLAC) labour management and clinical practice.

METHODS

Viable, singleton pregnancies from January 1, 2016, to December 31, 2018, undergoing TOLAC were extracted from the electronic medical record. Sixty randomly selected charts were reviewed for (1) consent, (2) induction methods, (3) oxytocin use, (4) continuous fetal monitoring, (5) admission indication, (6) examination regularity, (7) duration of dystocia before decision to perform cesarean delivery (CD), and (8) maternal complications.

RESULTS

The institutional vaginal birth after cesarean rate was 71%. Documented consent to TOLAC on admission was present in 50% of cases. Oxytocin augmentation was used in 38% of cases, and the median maximum dose was 4 mU/min (interquartile range [IQR] 3-7.5 mU/min). Delays in initiating oxytocin were identified in 47% of those patients. Decisions to deliver by cesarean were made after a median time of 5 hours and 40 minutes (IQR 3 hours and 30 minutes to 6 hours and 35 minutes) of failure to progress despite adequate contractions. After this decision, median time to delivery was 1 hour and 11 minutes (IQR 57 minutes to 2 hours and 16 minutes). Complications included postpartum hemorrhage (5%) and chorioamnionitis (6.7%). Surgical injury occurred in 10% of intrapartum CD. Peripartum complications were associated with delay in oxytocin implementation (χ² (1) = 9.80; P < 0.001) in secondary analysis.

CONCLUSION

Areas for QI were identified in (1) consent, (2) duration of dystocia before decision to proceed with CD and delay to CD, and (3) peripartum complications. We recognize the potential use of this as a tool to identify areas for QI and prospective study.

No. 382-Trial of Labour After Caesarean

OBJECTIVE

To provide evidence-based guidelines for the provision of a trial of labour after Caesarean section.

OUTCOMES

Fetal and maternal morbidity and mortality associated with vaginal birth after Caesarean and repeat Caesarean section.

EVIDENCE

MEDLINE database was searched for articles published from January 1, 1995, to October 31, 2017 using the key words "vaginal birth after Caesarean (Cesarean) section." The quality of evidence is described using the Evaluation of Evidence criteria outlined in the Report of the Canadian Task Force on the Periodic Health Exam.

VALIDATION

These guidelines were approved by the Clinical Practice Obstetrics Committee and the Board of the Society of Obstetricians and Gynaecologists of Canada.

RECOMMENDATIONS

No. 155-Guidelines for Vaginal Birth After Previous Caesarean Birth

OBJECTIVE

To provide evidence-based guidelines for the provision of a trial of labour (TOL) after Caesarean section.

OUTCOME

Fetal and maternal morbidity and mortality associated with vaginal birth after Caesarean (VBAC) and repeat Caesarean section.

EVIDENCE

MEDLINE database was searched for articles published from January 1, 1995, to February 28, 2004, using the key words "vaginal birth after Caesarean (Cesarean) section." The quality of evidence is described using the Evaluation of Evidence criteria outlined in the Report of the Canadian Task Force on the Periodic Health Exam.

RECOMMENDATIONS

VALIDATION: These guidelines were approved by the Clinical Practice Obstetrics and Executive Committees of the Society of Obstetricians and Gynaecologists of Canada.

Maternal and neonatal outcomes for women giving birth after previous cesarean

INTRODUCTION

Rising rates of caesarean section (CS) is an issue of particular concern. Recently, there has been research supporting Vaginal Births After Caesarean (VBAC), which is controversial. In Greece, over half of births in the country are by CS, placing Greece among countries with the highest CS rates. The aim of this study was to investigate the prevalence and the factors associated with VBACs and to compare the maternal/neonatal outcomes with a 'non-caesarean' control group.

METHODS

The data were evaluated and retrospectively gathered on archived singleton births, from medical records of a midwifery-led team, between May 2006 and May 2013. The target group of the study included mothers with a previous CS, who had a second birth. The sample consisted of 71 VBAC women and 583 who had normal spontaneous vaginal delivery (NSVD) as the 'non-caesarean' control group.

RESULTS

The duration of labour was longer for the VBACs compared with first-time mothers who gave birth naturally (for duration 481-720 min, 27% vs 10.3%, respectively), episiotomy was more common for VBAC (20.7% vs 7.9%), and epidural analgesia was more often for VBAC (68.4% vs 10%). The percentage of 1-min Apgar score in the range 0-7 in the VBAC group was 5%, and there was no significant difference in women who had NSVD (3.6%). The Apgar score in the 5th minute was always above 8 for both groups.

CONCLUSIONS

Severe maternal and neonatal complications are infrequent, and therefore the necessity arises for further continuous studies to ascertain the safety of VBAC.

Factors Associated with Trial of Labour and Mode of Delivery in Robson Group 5: A Select Group of Women With Previous Caesarean Section

OBJECTIVE

To determine the proportion of women in Robson group 5 (RG5) who were eligible for a trial of labour after Caesarean (TOLAC) and, among eligible candidates, identify determinants of having a TOLAC and subsequent vaginal delivery (VD).

METHODS

This population-based cohort study used data derived from the Nova Scotia Atlee Perinatal Database. Deliveries from 1998-2014 to women in RG5 (≥1 previous CS with a singleton term cephalic fetus) were included. Eligibility for a TOLAC was based on SOGC criteria. Multivariable logistic regression was used to identify characteristics independently associated with TOLAC and VD. The characteristics associated with VD were used in a logistic model to predict the theoretical probability of VD in women who did not have a TOLAC.

RESULTS

Of the 15 111 deliveries in RG5, 75.3% were by CS. Of the 14 763 eligible women, 5488 (37.2%) had a TOLAC, of which 3739 (68.1%) resulted in VD. Predictors of VD included high area-level income and either a CS without labour or a spontaneous VD in the preceding pregnancy. While mode of previous delivery also predicted TOLAC among eligible women, high area-level income was associated with reduced odds of TOLAC. The probability of VD in women who did not undergo TOLAC was estimated to be 47.1%, and the lowest CS rate attainable in RG5 was estimated at 46.3%.

CONCLUSIONS

Sociodemographic factors such as income and previous mode of delivery were associated with the rates of TOLAC and subsequent VD in eligible women, and suggest that the Caesarean section rate in RG5 could be safely reduced.

Trial of labour after caesarean section: Two-year analysis at a Portuguese centre

We conducted a retrospective study aimed at determining variables associated with a higher success rate for vaginal delivery after caesarean section, and assessing the impact of induction of labour. Secondarily, we aimed to describe our vaginal delivery and uterine rupture rates with the use of a controlled-release dinoprostone vaginal insert for cervical ripening. Of 292 women who met the inclusion criteria, induction of labour occurred in 48% (94% with dinoprostone). There was a non-significant difference between the vaginal delivery rate of spontaneous labour (57%) and induction of labour (33%), after adjusting for confounding variables. The success rate was influenced by a Bishop score ≥6, previous vaginal delivery and previous caesarean for dystocia or failed induction. There was only one case of uterine rupture, which was associated with dinoprostone use (overall rate 0.34%, 0.77% for dinoprostone). Impact statement Trial of labour after caesarean section is considered an alternative to elective repeat caesarean. Both present associated benefits and risks, the most fearsome of which is uterine rupture during labour (0.78% in term pregnancies). Induction is also possible but carries a higher risk of uterine rupture and lower success rate for vaginal birth. Prostaglandins have been of particular concern due to a higher risk of uterine scar rupture, estimated at 2% for dinoprostone; however, its use as a controlled-release vaginal insert has been under-reported. Our study confirms the reported impact of previous vaginal delivery, previous caesarean indication and Bishop score at admission on success rate for vaginal birth after caesarean. We were unable to prove a lower success rate for induction of labour after adjusting for other variables. Despite our study limitations, we report on the use of a controlled-release vaginal insert with 10mg of dinoprostone in 130 women with a uterine rupture rate of 0.77%, lower than previously reported and similar to the overall rate estimated for term pregnancies. This dinoprostone formulation may be safer than previously reported but larger studies, and preferably randomised controlled trials, are needed to confirm these findings.

Vaginal birth after caesarean delivery in Chinese women and Western immigrants in Shanghai

Recent studies show a steep rise in caesarean sections in China. Most couples are now eligible to apply for a second child. This retrospective cohort study compares the prevalence of trial of labour and vaginal birth after caesarean section among Chinese and foreign women in Shanghai. In total, 135 of 368 women underwent trial of labour (36.68%), and of those, 77 (57.04%) had a vaginal birth. After inclusion in a multivariate model, factors associated with trial of labour were maternal age <35 years with an adjusted odds ratio of 2.58 (1.49-4.46), absence of a history of ≥3 abortions (2.22 (1.08-4.57)), and European citizenship (1.94 (1.05-3.59)). The prevalence of trial of labour and vaginal birth seems to mirror rates found in countries of origin, but despite a high rate of caesarean section, Chinese women had a higher rate of vaginal birth after caesarean section than North American and Australian women, in particular. Impact statement What is already known on this subject: Caesarean section (CS) rates are rising worldwide. Repeat CS contributes largely to these rates, although vaginal birth after CS (VBAC) rates varies widely between countries. What the results of this study add: North American and Australian women who deliver in Shanghai have low rates of attempted trial of labour after CS (TOLAC) and VBAC, with European women having the highest rate of TOLAC, followed by Chinese women. Implications for clinical practice and/or further research: These findings might reflect different levels of acceptance in line with respective national trends. Studies evaluating the influence of cultural norms on birth preferences after CS are needed. Further research is also needed to assess the overall acceptance of TOLAC in the context of the softening of the one-child policy in China.

Maternal and perinatal outcomes associated with a trial of labour after previous caesarean section in sub-Saharan countries

OBJECTIVE

To assess the risks of uterine rupture, maternal and perinatal outcomes associated with a trial of labour (TOL) after one previous caesarean were compared with having an elective repeated caesarean section (ERCS) without labour in low-resource settings.

DESIGN

A prospective 4-year observational study.

SETTING

Senegal and Mali.

SAMPLE

A cohort of 9712 women with one previous caesarean delivery.

METHODS

Maternal and perinatal outcomes were compared between 8083 women who underwent a TOL and 1629 women who had an ERCS. Perinatal and maternal outcomes were then stratified according to the presence or absence of risk factors associated with vaginal birth after caesarean section. These outcomes were adjusted on maternal, perinatal and institutional characteristics.

MAIN OUTCOME MEASURES

The risks of uterine rupture, maternal complication and perinatal mortality associated with TOL after one previous caesarean as compared with ERCS, RESULTS: The risks of hospital-based maternal complication [adjusted odds ratio (OR) 1.52; 95% CI 1.09-2.13; P = 0.013] and perinatal mortality (adjusted OR 4.53; 95% CI 2.30-9.92; P < 0.001) were significantly higher in women with a TOL compared with women who had an ERCS. However, when restricted to low-risk women, these differences were not significant (adjusted OR 0.90, 95% CI 0.55-1.46, P = 0.68, and adjusted OR 1.13; 95% CI 0.75-1.86; P = 0.53, for each outcome, respectively). Uterine rupture occurred in 25 (0.64%) of 3885 low-risk women compared with 70 (1.66%) of 4198 women with unfavourable risk factors.

CONCLUSION

Low-risk women have no increased risk of maternal complications or perinatal mortality compared with women with one or more unfavourable factors.

TWEETABLE ABSTRACT

Low-risk women have a lower risk of maternal complications or perinatal mortality compared with high-risk women.

Trial of labour in twin pregnancies: a retrospective cohort study

OBJECTIVE

To assess the success rate of vaginal delivery among women with twin pregnancies; the Twin Birth Study has shown that vaginal delivery and caesarean section are equally safe for twin delivery but >40% of the planned vaginal delivery group delivered by caesarean section.

DESIGN

A retrospective cohort study.

SETTING

A tertiary medical centre.

POPULATION

A total of 2194 women with twin pregnancies not complicated with very low birthweight.

METHODS

Planned mode of delivery was documented in the woman's electronic record upon entering the delivery room. Information regarding maternal age at delivery, parity, gestational age, presentation, previous history of caesarean delivery, birthweight and Apgar score was collected from the obstetric electronic charts.

MAIN OUTCOME MEASURED

Rate of vaginal twin delivery.

RESULTS

Of the 2194 women included, 1311 twin pregnancies had planned caesarean delivery and 883 underwent a trial of labour. Of the 883 women who underwent a trial of labour, the rate of vaginal delivery was 86.9%, whereas the rates of caesarean delivery and combined vaginal-caesarean delivery were 11.1% and 2.0%, respectively. Presentation of second twin, gestational age and maternal age did affect the chances of success. Nulliparity [odds ratio (OR) 2.38, 95% confidence interval (95% CI) 1.4-4.05], Foley induction of labour (OR 2.33, 95% CI 1.38-3.91) and body mass index >30 kg/m(2) (OR 1.76, 95% CI 1.03-3) were independent risk factors for caesarean delivery.

CONCLUSIONS

The rate of vaginal delivery among women with twin pregnancies who undergo labour can be high, especially in women who laboured spontaneously and have delivered before.

TWEETABLE ABSTRACT

The rate of vaginal delivery of twins can be high, especially in women who have delivered before.

Is vaginal delivery safe after previous lower segment caesarean section in developing country?

Background:

To analyse the mode of delivery in trial of labour (TOL), incidence of successful vaginal deliveries and indications of repeat caesarean section (CS).

Materials and Methods:

Prospective selective study. Study population consisted of 367 pregnant women with previous one lower segment caesarean section (LSCS) in reproductive age group. These were grouped in to three groups, Group 1 (n = 239): Women, who were elected for repeat CS without a TOL. Group 2 (n = 76): Women, who were given TOL and delivered vaginally. Group 3 (n = 52): Women, who were given a TOL but due to failed trial, had to be taken for emergency repeat section. The maternal and foetal outcome was studied in all the groups.

Statistical Method Used:

The data was entered in the Microsoft excel worksheet, values expressed as mean ± SD. Chi-square test was done to compare the categorical variables among the groups. ANOVA (one-way analysis of variance) was done to compare the baseline characteristics of patients and time to delivery among the groups.

Results:

Out of 128 women who were given TOL, 76 (59.37%) vaginal birth after caesarean (VBAC) occurred, out of which 40 (52.63%) had spontaneous vaginal deliveries without augmentation of labour and 36 (47.36%) subjects had augmentation of labour with artificial rupture of membranes (ARMs) and oxytocin. A total of 52 women (40.62%) underwent emergency LSCS.

Conclusion:

Proper selection and counselling about clinically significant risks, women can be given TOL with careful monitoring and taken for emergency LSCS on minimal indication is the best answer to management of previous one CS in labour.

The effects of labor and delivery on maternal and neonatal outcomes in term twins: a retrospective cohort study

OBJECTIVE

To compare maternal and neonatal outcomes in twins undergoing a trial of labor versus pre-labor caesarean.

DESIGN

Retrospective cohort study.

SETTING

19 US hospitals from the Consortium on Safe Labor.

POPULATION

Of 2225 twin sets ≥36 weeks' gestation.

METHODS

Maternal (abruption, estimated blood loss, postpartum haemorrhage, transfusion, chorioamnionitis, hysterectomy, ICU admission, death) and neonatal outcomes (birth injury, 5-minute Apgar <7, NICU admission, RDS, TTN, sepsis, asphyxia, NICU length of stay, death) were compared between the trial of labour and pre-labour caesarean groups with univariate and multivariate logistic and linear regression analyses. Similar analyses were performed for actual delivery modes.

MAIN OUTCOME MEASURES

Maternal and neonatal outcomes.

RESULTS

Among the 2225 twin sets, 1078 had a trial of labour, and 65.9% of those delivered vaginally. There was an increased risk for postpartum haemorrhage [OR 2.5, 95% confidence interval (CI) 1.4-4.5] and blood transfusion (OR 1.9, 95%CI 1.2-3.2) for the trial of labour compared with pre-labour caesarean groups. Birth injury only occurred in the trial of labour group, 1% Twin A, 0.4% Twin B. Both twins had a higher risk of 5-minute Apgar <7 with trial of labour compared to pre-labour caesarean (A: OR 3.9, 95%CI 1.05-14.5; B: OR 3.9, 95%CI 1.3-12.3).

CONCLUSION

Term twins undergoing a trial of labour have increased maternal haemorrhage and transfusions along with neonatal birth trauma and lower Apgar scores, but these absolute neonatal occurrences were rare. Trial of labour in twins remains a safe and reasonable option in appropriately selected cases.

Ethnic disparities in repeat caesarean rates at Auckland Hospital

BACKGROUND

New Zealand guidelines recommend that information regarding childbirth choices be given to women with previous caesarean, so they can make informed decisions about their care. We hypothesised that rates of trial of labour (TOL) and vaginal birth after caesarean (VBAC) would vary by women's ethnicity.

AIM

To estimate the association of ethnicity with TOL and VBAC rates.

MATERIALS AND METHODS

Clinical data were used to identify women who gave birth at Auckland Hospital in 2006-2009 with history of previous caesarean eligible for TOL. Multivariable models were used to estimate the association of women's characteristics (ethnicity, age, socio-economic status (SES), height, body mass index, lead maternity carer, diabetes, hypertension, haemorrhage, labour induction, gestational age) with rates of TOL and VBAC.

RESULTS

In the study cohort of 2400 women, the TOL rate was 39.5%; the VBAC rate was 57.4%. Pacific women were twice as likely to have TOL, while Asian and non-New Zealand European women were half as likely to have VBAC, compared with New Zealand European women. Women in more deprived areas were more likely to have TOL, but SES was not associated with VBAC rates. Women under the care of private obstetricians were least likely to have TOL or VBAC.

CONCLUSIONS

There are ethnic disparities in TOL and VBAC rates at our hospital. Strategies need to be developed to ensure that women of all ethnicities have access to both options for mode of delivery.

VBAC: Is It Safe for Your Patients?

Vaginal birth after caesarean section (VBAC) is being increasingly considered as an alternative to elective repeat section, in order to help reduce overall caesarean rates and achieve improved perinatal outcomes. This review examines the evidence for the safety of VBAC compared to the traditional practice of "Once a caesarean, always a caesarean." It appears that the incidence of uterine rupture is much lower than previously thought (less than 1%), and that the rates of overall fetal and maternal mortality improve with the use of VBAC. A number of associated treatments such as epidural anesthesia and oxytocin use are also examined.