Trial of labor compared to repeat cesarean section in women with no other risk factors than a prior cesarean delivery

Trial of labor versus elective cesarean delivery for patients with two prior cesarean sections: a systematic review and meta-analysis

OBJECTIVE

Cesarean section (CS) rates have been on the rise globally, leading to an increasing number of women facing the decision between a Trial of Labor after two Cesarean Sections (TOLAC-2) or opting for an Elective Repeat Cesarean Section (ERCS). This study evaluates and compares safety outcomes of TOLAC and ERCS in women with a history of two previous CS deliveries.

METHODS

PubMed, MEDLINE, EMbase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for studies published until 30 June 2023. Eligible studies were included based on predetermined criteria, and a random-effects model was employed to pool data for maternal and neonatal outcomes.

RESULTS

Thirteen studies with a combined sample size of 101,011 women who had two prior CS were included. TOLAC-2 was associated with significantly higher maternal mortality (odds ratio (OR)=1.50, 95% confidence interval (CI)= 1.25-1.81) and higher chance of uterine rupture (OR = 7.15, 95% CI = 3.44-14.87) compared to ERCS. However, no correlation was found for other maternal outcomes, including blood transfusion, hysterectomy, or post-partum hemorrhage. Furthermore, neonatal outcomes, such as Apgar scores, NICU admissions, and neonatal mortality, were comparable in the TOLAC-2 and ERCS groups.

CONCLUSION

Our findings suggest an increased risk of uterine rupture and maternal mortality with TOLAC-2, emphasizing the need for personalized risk assessment and shared decision-making by healthcare professionals. Additional studies are needed to refine our understanding of these outcomes in the context of TOLAC-2.

Trial of labor after cesarean, vaginal birth after cesarean, and the risk of uterine rupture: an expert review

The decision to pursue a trial of labor after cesarean delivery is complex and depends on patient preference, the likelihood of successful vaginal birth after cesarean delivery, assessment of the risks vs benefits of trial of labor after cesarean delivery, and available resources to support safe trial of labor after cesarean delivery at the planned birthing center. The most feared complication of trial of labor after cesarean delivery is uterine rupture, which can have catastrophic consequences, including substantial maternal and perinatal morbidity and mortality. Although the absolute risk of uterine rupture is low, several clinical, historical, obstetrical, and intrapartum factors have been associated with increased risk. It is therefore critical for clinicians managing patients during trial of labor after cesarean delivery to be aware of these risk factors to appropriately select candidates for trial of labor after cesarean delivery and maximize the safety and benefits while minimizing the risks. Caution is advised when considering labor augmentation and induction in patients with a previous cesarean delivery. With established hospital safety protocols that dictate close maternal and fetal monitoring, avoidance of prostaglandins, and careful titration of oxytocin infusion when induction agents are needed, spontaneous and induced trial of labor after cesarean delivery are safe and should be offered to most patients with 1 previous low transverse, low vertical, or unknown uterine incision after appropriate evaluation, counseling, planning, and shared decision-making. Future research should focus on clarifying true risk factors and identifying the optimal approach to intrapartum and induction management, tools for antenatal prediction, and strategies for prevention of uterine rupture during trial of labor after cesarean delivery. A better understanding will facilitate patient counseling, support efforts to improve trial of labor after cesarean delivery and vaginal birth after cesarean delivery rates, and reduce the morbidity and mortality associated with uterine rupture during trial of labor after cesarean delivery.

Delivery mode and fetal outcome in attempted vaginal deliveries after previous cesarean section: a nationwide register-based cohort study in Finland

PURPOSE

Even though the risks and advantages of repeat Cesarean sections (CSs) and vaginal births after cesarean section (VBACs) are well studied, there is a scarcity of information on the effects of previous CS on maternal and fetal outcomes during subsequent deliveries. The aim of this study is to evaluate delivery mode and fetal outcomes in a trial of labor after cesarean section (TOLAC).

METHODS

In this nationwide retrospective cohort study, data from the National Medical Birth Register (MBR) were used to evaluate the outcomes of TOLACs. TOLACs were compared to the outcomes of the trial of labor after previous successful vaginal delivery. A multivariable logistic regression model was used to assess the primary outcomes (delivery mode, neonatal intensive care unit, and perinatal/neonatal mortality). Adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were used for comparison.

RESULTS

A total of 29 352 (77.0%) women attempted vaginal delivery in the TOLAC group. In the control group, 169 377 (97.2%) women attempted vaginal delivery. The adjusted odds for urgent CS (aOR 13.05, CI 12.59-13.65) and emergency CS (aOR 3.65, CI 3.26-4.08) were notably higher in the TOLAC group when compared to the control group. The odds for neonatal intensive care unit treatment (aOR 2.05, CI 1.98-2.14), perinatal mortality (aOR 2.15, CI 1.79-2.57), and neonatal mortality (aOR 1.75, CI 1.20-2.49) were higher in the TOLAC group.

CONCLUSIONS

The odds for emergency CS were higher among women who underwent TOLAC. The odds for neonatal intensive care and perinatal mortality were also higher, and further research is needed to identify those expecting women who are better suited for TOLAC to minimize the risk for a neonate. The results of this study should be acknowledged by the mother and the clinician when considering the possibility of vaginal births after cesarean section.

Trial of labour versus elective caesarean delivery for estimated large for gestational age foetuses after prior caesarean delivery: a multicenter retrospective study

BACKGROUND

Lower rates of successful trial of labor after cesarean (TOLAC) in association with fetal macrosomia were previously reported. This study aimed to compare TOLAC to elective caesarean delivery (CD) in women with estimated fetal weight large for gestational age (eLGA) and a prior CD. Primary outcome was to analyse the mode of delivery in case of TOLAC. Secondary outcome was to compare maternal and foetal morbidity.

METHODS

We conducted a retrospective, descriptive, multicentric, cohort study in five maternity units between January and December 2020. Inclusion criteria were: women with a single prior CD and eLGA or neonatal weight > 90th percentile with singleton pregnancy and gestational age ≥ 37 weeks.

MAIN OUTCOME MEASURES

rate of vaginal delivery, maternal and fetal morbidity including: shoulder dystocia, neonatal hospitalization, fetal trauma, neonatal acidosis, uterine rupture, 3^rd and 4^th perineal tears, post-partum hemorrhage, and a need for blood transfusion.

RESULTS

Four hundred forty women met inclusion criteria, including 235 (53.4%) eLGA. 170 (72.3%) had a TOLAC (study group) and 65 (27.7%) an elective CD (control). 117 (68.82%) TOLAC had a vaginal delivery. No significant differences were found between the two groups in the rates of: postpartum haemorrhage, transfusion, Apgar score, neonatal hospitalization, and foetal trauma. Cord lactate was higher in the case of TOLAC (3.2 vs 2.2, p < 0.001). Median fetal weight was 3815 g (3597-4085) vs. 3865 g (3659-4168): p = 0.068 in the study vs. controls group respectively.

CONCLUSION

TOLAC for eLGA fetuses is legitimate because there is no difference in maternal-fetal morbidity, and the CD rate is acceptable.

Use of labor analgesia in trials of labor after previous cesarean section: A nationwide register-based analysis in Finland

OBJECTIVES

The literature concerning the overall use of labor analgesia among women with trials of labor after cesarean section (TOLAC) is lacking. The primary aim of this study is to report the rate of different labor analgesia methods among women with TOLAC. The secondary aim was to compare the use of labor analgesia between women with the first TOLAC and control group consisting of nulliparous women.

STUDY DESIGN

Data from the National Medical Birth Register was used to evaluate the usage of labor analgesia in TOLACs. The use of labor analgesia in the first TOLAC is compared to the pregnancies of nulliparous women. The analgesia methods were stratified into neuraxial analgesia, pudendal, paracervical, nitrous oxide, other medical, other non-medical, and no analgesia. These are analyzed as categorized dichotomy (yes or no) variables.

RESULTS

A total of 38 596 TOLACs as second pregnancy of the mother was found during our study period. The control group consisted of a total of 327 464 pregnancies of nulliparous women. Epidural analgesia (61.6% vs 67.1%), nitrous oxide (56.1% vs 62.0%), and non-medical analgesia (30.1% vs 35.0%) were less consumed among women with TOLAC. The rate of spinal analgesia was higher among women with TOLAC (10.1% vs 7.6%) when compared to the control group. However, when only vaginal deliveries were included, the rate of labor analgesia increased especially in the TOLAC group.

CONCLUSIONS

The main finding of this study is that women with TOLAC had a generally lower rate of labor analgesia. However, the rate of spinal analgesia was higher among women with TOLAC when compared to the control group, however. The results of this study inform midwives, obstetricians, and anesthesiologists on current practices and how to improve the analgetic treatment in TOLAC.

Early childhood educational outcomes of children associated with vaginal birth after cesarean delivery

BACKGROUND

Rates of vaginal birth after cesarean delivery have decreased and cesarean delivery rates have increased in the last 2 decades. Evidence on short-term neonatal outcomes is available, but data on long-term childhood outcomes following vaginal birth after cesarean delivery are insufficient. Long-term childhood outcome data are essential in decision-making regarding mode of delivery.

OBJECTIVE

This study aimed to evaluate the association between delivery mode and long-term educational outcomes of the children of pregnant individuals with a previous cesarean delivery.

STUDY DESIGN

This was a retrospective cohort study linking Rhode Island third-grade education data from 2014 to 2017 to birth certificate data. Data were obtained from a statewide database using Department of Education data, and were linked to Department of Health birth certificate data. Participants were children of multiparous women who were term, singleton births without congenital anomalies. Children delivered by primary cesarean delivery were excluded. The exposure was mode of delivery classified as vaginal birth after cesarean delivery, repeated cesarean delivery, or repeated vaginal birth. The primary outcome was children's third-grade reading and math proficiency. Bivariate analyses were conducted to assess differences in demographic variables. Bivariable and multivariable log-binomial regression was used to examine the association between subject proficiency and predictors including mode of delivery, maternal education, sex, child race or ethnicity, and lunch subsidy.

RESULTS

Of the 10,923 children who met the inclusion criteria, 2.0% were delivered by vaginal birth after cesarean delivery, 22.0% by repeated cesarean delivery, and 76.0% by repeated vaginal delivery. After adjustment for confounders, there was no difference in reading proficiency (adjusted risk ratio, 0.98; 95% confidence interval, 0.84-1.15) or math proficiency (adjusted risk ratio, 0.99; 95% confidence interval, 0.84-1.15) between those born by vaginal birth after cesarean delivery and those born by repeated cesarean delivery. There was no difference found in either proficiency between children born by repeated vaginal birth and those born by repeated cesarean delivery (reading: adjusted risk ratio, 0.97; 95% confidence interval, 0.93-1.01; math: adjusted risk ratio, 0.97; 95% confidence interval, 0.92-1.02).

CONCLUSION

In comparison with repeated cesarean delivery, both vaginal birth after cesarean delivery and repeated vaginal birth were not associated with differences in educational outcomes. This may aid in counseling about long-term safety outcomes regarding vaginal birth after cesarean delivery and may assist in shared decision-making when selecting between trial of labor after cesarean delivery and repeated cesarean delivery.

Planned mode of birth after previous cesarean section: A structured review of the evidence on the associated outcomes for women and their children in high-income setting

In many high-income settings policy consensus supports giving pregnant women who have had a previous cesarean section a choice between planning an elective repeat cesarean section (ERCS) or planning a vaginal birth after previous cesarean (VBAC), provided they have no contraindications to VBAC. To help women make an informed decision regarding this choice, clinical guidelines advise women should be counseled on the associated risks and benefits. The most recent and comprehensive review of the associated risks and benefits of planned VBAC compared to ERCS in high-income settings was published in 2010 by the US Agency for Healthcare Research and Quality (AHRQ). This paper describes a structured review of the evidence in high-income settings that has been published since the AHRQ review and the literature in high-income settings that has been published since 1980 on outcomes not included in the AHRQ review. Three databases (MEDLINE, EMBASE, and PsycINFO) were searched for relevant studies meeting pre-specified eligible criteria, supplemented by searching of reference lists. Forty-seven studies were identified as meeting the eligibility criteria and included in the structured review. The review suggests that while planned VBAC compared to ERCS is associated with an increased risk of various serious birth-related complications for both the mother and her baby, the absolute risk of these complications is small for either birth approach. The review also found some evidence that planned VBAC compared to ERCS is associated with benefits such as a shorter length of hospital stay and a higher likelihood of breastfeeding. The limited evidence available also suggests that planned mode of birth after previous cesarean section is not associated with the child’s subsequent risk of experiencing adverse neurodevelopmental or health problems in childhood. This information can be used to manage and counsel women with previous cesarean section about their subsequent birth choices. Collectively, the evidence supports existing consensus that there are risks and benefits associated with both planned VBAC and ERCS, and therefore women without contraindications to VBAC should be given an informed choice about planned mode of birth after previous cesarean section. However, further studies into the longer-term effects of planned mode of birth after previous cesarean section are needed along with more research to address the other key limitations and gaps that have been highlighted with the existing evidence.

Feeding Practices, Maternal and Neonatal Outcomes in Vaginal Birth after Cesarean and Elective Repeat Cesarean Delivery

Cesarean section rates are constantly rising, and the number of women with a prior cesarean considering a delivery mode for their next labor is increasing. We aimed to compare maternal and neonatal outcomes and feeding method in women undergoing vaginal birth after cesarean (VBAC) versus elective repeat cesarean delivery (ERCD). This was a retrospective cohort study of women with one prior cesarean delivery (CD) and no previous vaginal births, delivering vaginally or by a CD in a single institution between 2016 and 2018. 355 live singleton spontaneous vaginal and cesarean deliveries were included. 121 women delivered vaginally and 234 had a CD. Neonates born by a CD were more likely to have higher birth weight (p < 0.001), higher weight at discharge (p < 0.001), macrosomia (p = 0.030), lose >10% of their body mass (p = 0.001), be mixed-fed (p < 0.001), and be hospitalized longer (p < 0.001). Children born vaginally were more likely to be exclusively breastfed (p < 0.001). Women undergoing VBAC were more likely to deliver preterm (p = 0.006) and post-term (p < 0.001), present with PROM (p < 0.001), have greater PROM latency period (p < 0.001), and experience intrahepatic cholestasis of pregnancy (p = 0.029), postpartum anemia (p < 0.001), and peripartum blood loss >1 L (p = 0.049). The incidence of anemia during pregnancy was higher in the ERCD cohort (p = 0.047). Women undergoing VBAC are more likely to breastfeed their children, perhaps for the same reason they choose the vaginal method of delivery, as vaginal delivery and breastfeeding along with antibiotic use, are the most important factors decreasing the risk for future diseases in their offspring.

Correlation Between Previous Caesarean Section and Adverse Maternal Outcomes Accordingly With Robson Classification: Systematic Review and Meta-Analysis

Background: The increasing rates of Caesarean section (CS) beyond the WHO standards (10–15%) pose a significant global health concern.

Objective: Systematic review and meta-analysis to identify an association between CS history and maternal adverse outcomes for the subsequent pregnancy and delivery among women classified in Robson classification (RC).

Search Strategy: PubMed/Medline, EbscoHost, ProQuest, Embase, Web of Science, BIOSIS, MEDLINE, and Russian Science Citation Index databases were searched from 2008 to 2018.

Selection Criteria: Based on Robson classification, studies reporting one or more of the 14 adverse maternal outcomes were considered eligible for this review.

Data Collection: Study design data, interventions used, CS history, and adverse maternal outcomes were extracted.

Main Results: From 4,084 studies, 28 (n = 1,524,695 women) met the inclusion criteria. RC group 5 showed the highest proportion among deliveries followed by RC10, RC7, and RC8 (67.71, 32.27, 0.02, and 0.001%). Among adverse maternal outcomes, hysterectomy had the highest association after preterm delivery OR = 3.39 (95% CI 1.56–7.36), followed by Severe Maternal Outcomes OR = 2.95 (95% CI 1.00–8.67). We identified over one and a half million pregnant women, of whom the majority were found to belong to RC group 5.

Conclusions: Previous CS was observed to be associated with adverse maternal outcomes for the subsequent pregnancies. CS rates need to be monitored given the prospective risks which may occur for maternal and child health in subsequent births.

Trial of Labor After Cesarean in Twin Gestation with no prior vaginal delivery - Evidence from largest cohort reported

Objective

To investigate trial of labor after cesarean (TOLAC) success rates in twin gestations with no prior vaginal delivery.

Methods

A retrospective study of women with twin gestations who underwent a TOLAC and had no prior vaginal delivery during 2011–2020. TOLAC success and failure groups were compared.

Results

Of 675 twin gestations with a history of cesarean delivery and no prior vaginal delivery, 83 (12.3%) elected to undergo a TOLAC and 26 (31.3%) succeeded. Two (7.7%) women delivered by cesarean for the second twin after vaginal delivery of the first twin. Epidural analgesia was positively associated with TOLAC success (odds ratio [OR] 4.31, 95% confidence interval [CI] 1.56–11.94, P = 0.004). Uterine rupture occurred in two patients (3.5%) of the TOLAC failure group. The proportion of cases with low Apgar score (<7) at 5 min was higher in the TOLAC success group (4 [15.4%] versus 1 [1.8%]; OR 10.1, 95% CI 1.07–96.22, P = 0.032) and the neonatal composite adverse outcome rate was lower in this group (OR 0.22, 95% CI 0.07–0.69, P = 0.009).

Conclusion

TOLAC in women with twins with no prior vaginal delivery is associated with a low success rate. No independent predictors of successful TOLAC were identified.

Trial of Labor After Cesarean of Small for Gestational Age Neonates Among Women with No Prior Vaginal Delivery - a Retrospective Study

To evaluate the characteristics and outcomes of women who had never delivered vaginally and underwent a trial of labor after cesarean (TOLAC) of small for gestational age (SGA) neonates, and to identify risk factors for unplanned repeat cesarean delivery. A retrospective cohort study from two tertiary medical centers. All women undergoing a TOLAC with no prior vaginal delivery, delivering a singleton SGA neonate at term between 2005 and 2020 were included. Factors associated with successful vaginal delivery were examined by a multivariable analysis. Of the 255 women who met the inclusion criteria and underwent TOLAC, 72.2% delivered vaginally. In a multivariable analysis, maternal height [adjusted odds ratio (aOR) (95% CI): 1.10 (1.02-1.19), p = 0.012] and epidural administration [aOR (95% CI): 2.78 (1.0-7.73), p = 0.050] were positively independently associated with TOLAC success, and hypertensive disorders were negatively independently associated with TOLAC success [aOR (95% CI): 0.52 (0.004-0.74), p = 0.029]. The success rate of TOLAC among women with no prior vaginal delivery, delivering a SGA neonate is relatively high. Maternal height, hypertensive disorders, and epidural administration are independent factors associated with TOLAC success. Epidural administration is a modifiable factor and should be taken in consideration during TOLAC management.

Intrapartum cesarean delivery and the risk of perinatal complications in women with and without a single prior cesarean delivery

OBJECTIVE

To determine maternal and neonatal complications associated with an intrapartum cesarean delivery (CD) with and without a history of a previous CD.

METHODS

A retrospective cohort study of all women who underwent an unplanned intrapartum CD following a trial of labor in a university-affiliated tertiary hospital, between 2009 and 2016. Perinatal outcomes of women with and without a history of a previous CD were compared. Composite adverse maternal outcome included one or more of the following: postpartum hemorrhage, need for blood transfusion, or cesarean hysterectomy. Composite adverse neonatal outcome included one or more of the following: 5-min Apgar score <7, neonatal seizure, need for intubation, meconium-aspiration-syndrome, or hypoxic-ischemic encephalopathy.

RESULTS

During the study period, 42 275 women attempted vaginal delivery. Of them, 2229 (5.3%) women underwent an unplanned intrapartum CD and met inclusion criteria: 337 (15.1%) with (study group) and 1892 (84.9%) without (control group) a previous CD. Women without a previous CD were younger and were characterized by higher rates of nulliparity and induction of labor compared with women with a previous CD. Other demographic and obstetrical characteristics did not differ between the groups. Indications for CD were also comparable between the groups. Uterine rupture complicated 2.3% of trials of labor among women with a previous CD. Adverse maternal (2.7% vs 2.9%, P = 1.0) and neonatal (3.9% vs 4.3%, P = 0.88) outcomes were comparable between the groups. After adjusting for potential confounders, a previous CD was not associated independently with adverse maternal outcomes (adjusted odds ratio [aOR] 0.86, 95% confidence interval [CI] 0.31-2.38; P = 0.78) or neonatal outcomes (aOR 0.79, 95% CI 0.36-1.75; P = 0.56).

CONCLUSION

Our study provides evidence that perinatal outcomes of intrapartum CD delivery among women with a previous CD do not differ from those in women without a previous CD. These findings might improve the consultation and informed decision-making process for couples considering a trial of labor after CD.

Ultrasonic assessment of cesarean section scar to vesicovaginal fold distance: an instrument to estimate pre-labor uterine rupture risk

BACKGROUND

The number of Cesarean sections (CS) is growing worldwide, intensifying the risk of complications in subsequent pregnancies and leading to increased maternal and fetal morbidity and mortality . In particular, the literature shows a higher risk of uterine rupture (UR) in subsequent pregnancy with trial of labor after cesarean section (TOLAC) Furthermore, there are few data about pre-labor UR in scarred uteri.

OBJECTIVE

Since the key factor for management is timing, the aim of this study was to evaluate the accuracy of prenatal ultrasound (US) of scars in the early determining of pre-labor UR risk in women with a previous CS during their subsequent pregnancy.

METHODS

From April 2014 to November 2018 a retrospective analysis was performed in order to evaluate the scar to vesicovaginal fold (VVF) distance in three patients with pre-labor UR and in 60 cases of the control group.

RESULTS

The periconceptional CS scar-VVF distance in the three UR cases resulted significantly increased compared to the controls (23.7 ± 3.5 mm vs 2.3 ± 2.7 mm, p < 005); moreover, a time interval of less than 18 months and a previous pre-labor preterm CS were found as known risk factors.

CONCLUSION

In this study, a higher uterine incision due to placenta previa or isthmic myoma seems to be correlated with a major risk of UR. Therefore, periconceptional US examination of CS-VVF distance, (which represents the level of the previous CS), seems to be a useful predictive factor of pre-labor UR in subsequent pregnancies.

Implementation of machine learning models for the prediction of vaginal birth after cesarean delivery

OBJECTIVE

Accurate prediction of vaginal birth after cesarean is crucial for selecting women suitable for a trial of labor after cesarean (TOLAC). We sought to develop a machine learning (ML) model for prediction of TOLAC success and to compare its accuracy with that of the MFMU model.

METHODS

All consecutive singleton TOLAC deliveries from a tertiary academic medical center between February 2017 and December 2018 were included. We developed models using the following ML algorithms: random forest (RF), regularized regression (GLM), and eXtreme gradient-boosted decision trees (XGBoost). For developing the ML models, we disaggregated BMI into height and weight. Similarly, we disaggregated prior arrest of progression into prior arrest of dilatation and prior arrest of descent. We applied a nested cross-validation approach, using 100 random splits of the data to training (80%, 792 samples) and testing sets (20%, 197 samples). We used the area under the precision-recall curve (AUC-PR) as a measure of accuracy.

RESULTS

Nine hundred and eighty-nine TOLAC deliveries were included in the analysis with an observed TOLAC success rate of 85.6%. The AUC-PR in the RF, XGBoost and GLM models were 0.351±0.028, 0.350±0.028 and 0.336±0.024, respectively, compared to 0.325±0.067 for the MFMU-C. The algorithms performed significantly better than the MFMU-C (p-values = .0002, .0004, .0393 for RF, XGBoost, GLM respectively). In the XGBoost model, eight variables were sufficient for accurate prediction. In all ML models, previous vaginal delivery and height were among the three most important predictors of TOLAC success. Prior arrest of descent contributed to prediction more than prior arrest of dilatation, maternal height contributed more than weight.

CONCLUSION

All ML models performed significantly better than the MFMU-C. In the XGBoost model, eight variables were sufficient for accurate prediction. Prior arrest of descent and maternal height contribute to prediction more than prior arrest of dilation and maternal weight.

Ultrasonic assessment has high sensitivity for pregnant women with previous cesarean section occurring uterine dehiscence and rupture: A STARD-compliant article

To investigate the diagnostic performance of ultrasound (US) for pregnant women with previous caesarean section (CS) occurring lower uterine segment (LUS) dehiscence and rupture.107 pregnant women with previous CS and LUS thickness of 1.0 mm or less were recruited, the LUS and myometrium was measured, and US findings suggestive of uterine rupture were compared with findings at laparotomy. The included pregnant women were assigned into 2 groups, including 64 pregnant women had vaginal delivery at full-term and 43 pregnant women underwent repeat CS at preterm.US findings suggestive of uterine rupture and dehiscence occurred in 18 women and 89 women, respectively; ten of them developed uterine rupture, and the incidence of uterine rupture was 9.34% (10/107). The sensitivity, specificity, accuracy, positive, and negative predictive values of US for the evaluation of LUS dehiscence and rupture were 100.0%, 91.8%, 92.5%, 55.6%, and 100.0%, respectively. There was no severe maternal obstetric complication, 1 fetus died, and the other fetuses were born with a 5-minute Apgar score of 7 to 10.US has high sensitivity and specificity for pregnant women with previous CS occurring LUS dehiscence and rupture.

Low risk pregnancies after a cesarean section: Determinants of trial of labor and its failure

Introduction

In pregnancies after a previous cesarean section (CS), a planned repeat CS delivery has been associated with excess risk of adverse outcome. However, also the alternative, a trial of labor after CS (TOLAC), has been associated with excess risks. A TOLAC failure, involving a non-planned CS, carries the highest risk of adverse outcome and a vaginal delivery the lowest. Thus, the decision regarding delivery mode is pivotal in clinical handling of these pregnancies. However, even with a high TOLAC rate, as seen in Norway, repeat CSs are regularly performed for no apparent medical reason. The objective of the present study was to assess to which extent demographic, socioeconomic, and health system factors are determinants of TOLAC and TOLAC failure in low risk pregnancies, and whether any effects observed changed with time.

Materials and methods

The study group comprised 24 645 second deliveries (1989–2014) after a first delivery CS. Thus, none of the women had prior vaginal deliveries or more than one CS. Included pregnancies were low risk, cephalic, single, and had gestational age ≥ 37 weeks. Data were obtained from the Medical Birth Registry of Norway (MBRN). The exposure variables were (second delivery) maternal age, length of maternal education, maternal country of origin, size of the delivery unit, health region (South-East, West, Mid, North), and maternal county of residence. The outcomes were TOLAC and TOLAC failure, as rates (%), relative risk (RR) and relative risk adjusted (ARR). Changes in determinant effects over time were assessed by comparing rates in two periods, 1989–2002 vs 2003–2014, and including these periods in an interaction model.

Results

The TOLAC rate was 74.9%, with a TOLAC failure rate of 16.2%, resulting in a vaginal birth rate of 62.8%. Low TOLAC rates were observed at high maternal age and in women from East Asia or Latin America. High TOLAC failure rates were observed at high maternal age, in women with less than 11 years of education, and in women of non-western origin. The effects of health system factors, i.e. delivery unit size and administrative region were considerable, on both TOLAC and TOLAC failure. The effects of several determinants changed significantly (P < 0.05) from 1989–2002 to 2003–2014: The association between non-TOLAC and maternal age > 39 years became weaker, the association between short education and TOLAC failure became stronger, and the association between TOLAC failure and small size of delivery unit became stronger.

Conclusion

Low maternal age, high education, and western country of origin were associated with high TOLAC rates, and low TOLAC failure rates. Maternity unit characteristics (size and region) contributed with effects on the same level as individual determinants studied. Temporal changes were observed in determinant effects.

Risk score for failed trial of vaginal birth after a previous cesarean section including data of labor course

AIM

There is much discussion about the advantages and disadvantages of a trial of labor after cesarean (TOLAC). Some data suggest the greater the likelihood of success, the lower the risks of TOLAC. Our goal was to identify clinical and demographic variables associated with a failed TOLAC, available at admission for spontaneous labor and until 3 h later, with the aim of building two scores for risk of failed TOLAC.

METHODS

This is a nested case-control study with live births to women with one previous cesarean, in a public Brazilian teaching hospital. Preterm, induction, noncephalic presentations, twins, fetal malformations were excluded. Cases were failed TOLAC, and controls, the successful TOLAC. It was accessed the association of the cases with 20 variables (P < 0.05). Associated variables were tested in multivariate analysis to build the scores, which were internally validated.

RESULTS

We included 260 TOLAC, 42 cases and 218 controls. We found 11 variables associated with failed TOLAC. In the score to be applied at admission, we included hypertension, fundal height, previous vaginal birth and dilatation at admission. In the second score hypertension, fundal height at admission, membrane status and difference in dilatation 3 h after admission. Both scores presented good performance in the receiver-operator curve (areas under curve: 0.73 and 0.84, respectively). Both scores were translated into nomograms for clinical use.

CONCLUSION

Two scores were built for risk of failed TOLAC, to be applied at admission and 3 h later. We believe that choosing the more favorable cases makes risks of TOLAC lower.

Trial of labor after cesarean (TOLAC) in women with premature rupture of membranes. J Matern Fetal Neonatal Med 2019;33:2976-2982. [PMID: 30652525 DOI: 10.1080/14767058.2019.1566312]

Introduction: The aim of this study was to assess the success rate of a trial of labor after a previous cesarean section (TOLAC) in the settings of premature rupture of membranes (PROM) and to compare conservative management with spontaneous labor and induction of labor.Methods: This was a retrospective cohort study conducted in a single tertiary care center between January 2011 and March 2017. Women with singleton pregnancy and a previous cesarean section (CS) who presented with PROM and underwent TOLAC were included. Outcomes and rate of successful vaginal delivery after induction of labor were compared to conservative treatment and spontaneous labor.Results: Among 830 women who met the inclusion criteria, 723 (87.1%) had a spontaneous onset of labor following PROM and 107 (12.9%) had an induction of labor. The rate of successful TOLAC was similar between the groups (75.7 vs. 81.6%, respectively, p = .22). However, induction of labor was associated with an increased risk for uterine rupture (1.87 vs. 0.96%, p < .001), operative complications (6.7 vs. 2.3%, p < .001), and composite maternal postpartum complications (21.4 vs. 10.7%, respectively, p = .014) compared to conservative management with spontaneous initiation of labor. There was no difference in neonatal outcome between the groups.Conclusion: Induction of labor following PROM in women with a previous CS is associated with high successful vaginal delivery rate. However, the risk for uterine rupture and operative and maternal complications is significantly increased compared to spontaneous initiation of labor.

Elective repeat cesarean delivery in women eligible for trial of labor in Brazil

OBJECTIVE

To assess the hospital, maternal, and obstetric characteristics associated with elective repeat cesarean delivery (ERCD) among women eligible for trial of labor after cesarean (TOLAC) delivery in Brazil.

METHODS

The present data were retrieved from the Birth in Brazil study, a national hospital-based cohort study conducted during 2011-2012. Data were collected from medical records and by interview. Univariate and hierarchical multiple logistic regression analyses were performed to analyze factors associated with ERCD among women with a previous cesarean delivery who were eligible for TOLAC.

RESULTS

Among 2295 women considered eligible for TOLAC, 1516 (66.1%) had an ERCD; the overall cesarean delivery rate was 79.4%. In the private sector, almost all deliveries (95.3%) were performed by ERCD. In the public sector, ERCD was associated with socioeconomic (more years of schooling), obstetric (women's preference, no previous vaginal delivery, macrosomia), and hospital (mixed hospital, location in noncapital city, fewer than 1500 deliveries per year) characteristics.

CONCLUSION

The ERCD rate in Brazil was high even in a low-risk group, indicating that nonclinical factors may be driving the decision for cesarean delivery. Efforts aiming to reduce cesarean deliveries in Brazil should target women with a previous cesarean delivery.

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.

Operative technique at caesarean delivery and risk of complete uterine rupture in a subsequent trial of labour at term. A registry case-control study

Objective

To estimate the relation of single-layer closure at previous caesarean delivery, and other pre-labour and intra-partum risk factors for complete uterine rupture in trial of vaginal birth after a caesarean (TOLAC) at term.

Study design

Population-based case-control study. We identified all women (n = 39 742) recorded in the Danish Medical Birth Registry (DMBR) during a 12-year period (1997–2008) with a singleton pregnancy at term and TOLAC. Among these, all women with a complete uterine rupture were identified (cases). Information from the registry was validated against medical records. Controls were selected in the DMBR as the following two births with TOLAC at term and no uterine rupture. Detailed information from cases and controls was collected from manual review of medical records. Main outcome measure was complete uterine rupture during TOLAC at term.

Results

Upon validation, 175 cases and 272 controls met the above criteria. After adjustment for possible confounding factors there was no association between single layer closure and uterine rupture (aOR 1.38, CI: 0.88–2.17). Significant risk factors were: Induction with an unfavourable cervix (aOR 2.10 CI: 1.19–3.71), epidural (aOR 2.17 CI 1.31–3.57), augmentation by oxytocin for more than one hour (aOR 2.03 CI: 1.20–3.44), and birth weight ≥ 4000g (aOR 2.65 CI 1.05–6.64). Previous vaginal delivery (aOR 0.41 CI: 0.25–0.68) and inter-delivery interval of more than 24 months (aOR 0.38 CI: 0.18–0.78) reduced the risk of uterine rupture.

Conclusion

Single-layer uterine closure did not remain significantly associated to uterine rupture during TOLAC at term after adjustment for confounding factors. Induction of labour with an unfavourable cervix, birth weight ≥ 4000g and indicators of prolonged labour were all major risk factors for uterine rupture.

[Risk of uterine rupture in vaginal birth after cesarean: Systematic review]

OBJECTIVE

To assess the risk of uterine rupture (UR) in attempted vaginal birth after cesarean and to identify risk factors.

METHODS

Systematic review by consulting the following databases: PubMed (MEDLINE), Cochrane Library Plus, Embase, Nursing@Ovid, Cuidatge and Dialnet. The search was conducted between January and March 2015. MeSH descriptors used were: vaginal birth after cesarean; uterine rupture; labor induced and labor obstetric or trial of labor. There were no restrictions on date or language. The selection of articles was performed by 2 independent reviewers, standardized and unblinded. A critical review of the summary was conducted, and if was necessary, the full text was consulted. Prospective and retrospective documents were included.

RESULTS

A total of 39 documents were included for their relevance and interest. Few clinical trials were found. The UR incidence on the results of the studies analyzed ranged from 0.15-0.98% in spontaneous labor; 0.3-1.5% in stimulation and induction with oxytocin, and 0.68-2.3% in prostaglandin inductions.

CONCLUSIONS

The success of vaginal birth after cesarean is important and improves when conditions are optimal. However it is not without risks, the main one being UR. Induction of labor with oxytocin and/or prostaglandins appears as the main risk factor, while the spontaneous onset of labor and a prior vaginal birth are protective factors.

Uterine rupture without previous caesarean delivery: a population-based cohort study

OBJECTIVE

To determine incidence and patient characteristics of women with uterine rupture during singleton births at term without a previous caesarean delivery.

STUDY DESIGN

Population based cohort study. Women with term singleton birth, no record of previous caesarean delivery and planned vaginal delivery (n=611,803) were identified in the Danish Medical Birth Registry (1997-2008). Medical records from women recorded with uterine rupture during labour were reviewed to ascertain events of complete uterine rupture. Relative Risk (RR) and adjusted Relative Risk Ratio (aRR) of complete uterine rupture with 95% confidence intervals (95% CI) were ascertained according to characteristics of the women and of the delivery.

RESULTS

We identified 20 cases with complete uterine rupture. The incidence of complete uterine rupture among women without previous caesarean delivery was about 3.3/100,000 deliveries. Multiparity (RR 8.99 (95% CI 1.86-43.29)), induction of labour (RR 3.26 (95% CI 1.24-8.57)), epidural analgesia (RR 10.78 (95% CI 4.25-27.39)), and augmentation by oxytocin (RR 9.50 (95% CI 3.15-28.63)) were associated with uterine rupture. Induction of labour was not significantly related to uterine rupture when adjusted for parity, epidural analgesia and augmentation by oxytocin.

CONCLUSION

Although uterine rupture is rare, its association with epidural analgesia and augmentation of labour with oxytocin in multipara should be considered. Thus, vigilance should be exercised when labour is obstructed and there is need for epidural analgesia and/or augmentation by oxytocin in multiparous women. Due to the rare occurrence of uterine rupture caution should be exerted when interpreting the findings of this study.

The risk of uterine rupture is not increased with single- compared with double-layer closure: a Swedish cohort study

OBJECTIVE

To compare single- with double-layer closure of the uterus for the risk of uterine rupture in women attempting vaginal birth after one prior caesarean delivery.

DESIGN

Cohort study.

SETTING

Sweden.

POPULATION

From a total of 19 604 nulliparous women delivered by caesarean section in the years 2001-2007, 7683 women attempting vaginal birth in their second delivery were analysed.

METHODS

Data from population-based registers were linked to hospital-based registers that held data from maternity and delivery records. Logistic regression was used to estimate the risk of uterine rupture after single- or double-layer closure of the uterus. Results are presented as odds ratios (ORs) with 95% confidence intervals (95% CIs).

MAIN OUTCOME MEASURE

Uterine rupture.

RESULTS

Uterine rupture during labour occurred in 103 (1.3%) women. There was no increased risk of uterine rupture when single- was compared with double-layer closure of the uterus (OR 1.17; 95% CI 0.78-1.76). Maternal factors associated with uterine rupture were: age ≥35 years and height ≤160 cm. Factors from the first delivery associated with uterine rupture in a subsequent delivery were: infection and giving birth to an infant large for gestational age. Risk factors from the second delivery were induction of labour, use of epidural analgesia, and a birthweight of ≥4500 g.

CONCLUSIONS

There was no significant difference in the rate of uterine rupture when single-layer closure was compared with double -layer closure of the uterus.