Trial of labor after 40 weeks' gestation in women with prior cesarean

Trial of labor after cesarean in primiparous women with fetal macrosomia

KEY MESSAGE

Spontaneous labor onset, epidural anesthesia and prior cesarean for non-arrest disorders are strong predictors of successful vaginal birth after cesarean in women delivering a macrosomic fetus.

PURPOSE

Lower rates of successful vaginal birth after cesarean in association with increasing birthweight were previously reported. We aimed to determine the factors associated with successful trial of labor after cesarean (TOLAC) among primiparous women with fetal macrosomia.

METHODS

A retrospective cohort study conducted during 2005-2019 at two university hospitals, including all primiparous women delivering a singleton fetus weighing ≥ 4000 g, after cesarean delivery at their first delivery. A multivariate analysis was performed to evaluate the characteristics associated with TOLAC success (primary outcome).

RESULTS

Of 551 primiparous women who met the inclusion criteria, 50.1% (n = 276) attempted a TOLAC and 174 (63.0%) successfully delivered vaginally. In a multivariate analysis, spontaneous onset of labor (aOR [95% CI] 3.68 (2.05, 6.61), P < 0.001), epidural anesthesia (aOR [95% CI] 2.38 (1.35, 4.20), P = 0.003) and history of cesarean delivery due to non-arrest disorder (aOR [95% CI] 2.25 (1.32, 3.85), P = 0.003) were the only independent factors associated with TOLAC success. Successful TOLAC was achieved in 82.0% (82/100) in the presence of all three favorable factors, 61.3% (65/106) in the presence of two factors and 38.6% (27/70) in the presence of one or less of these three factors (P < 0.001).

CONCLUSION

Spontaneous onset of labor, epidural anesthesia and prior cesarean delivery due to non-arrest disorders were independently associated with higher vaginal birth after cesarean rate among women with fetal macrosomia, with an overall favorable success rate in the presence of these factors. These findings should be implemented in patient counseling in those contemplating a vaginal birth in this setting.

Professional ethics, VBAC and COVID-19 pandemic: A challenge to be resolved (Review)

Since the declaration of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic by the World Health Organization (WHO) on March 11, 2020, the entire healthcare system is trying to adapt its capabilities to a challenge that induces a deep and continuous metamorphosis of people, strategies and policies. The right to proper health care is universal, and the patient's autonomy must be respected even in ambiguous times. In the context of increased Cesarean section (CS) rates, the women's desire to achieve vaginal birth after Cesarean section (VBAC) is becoming more articulate, and healthcare professionals need to adapt their approaches regarding the mode of delivery. But how to balance this aspect with respect to the paucity of resources during the pandemic, without infringing the fundamental rights and ethical principles is a demanding question. This article describes a clinical ethical decision-making framework for recommending trial of labor after Cesarean section (TOLAC), and individualized management of VBAC cases tailored upon the new circumstances dictated by the SARS-CoV-2 pandemic.

Risk of Uterine Rupture with Vaginal Birth after Cesarean in Twin Gestations

BACKGROUND

Women with a previous cesarean delivery may attempt a subsequent vaginal birth or repeat cesarean. Vaginal birth after cesarean carries a greater risk of uterine rupture, defined as the disruption of all uterine layers, resulting in maternal-fetal morbidity or mortality. It is unclear how the risk of uterine rupture compares in patients with twin gestations who undergo different delivery methods.

OBJECTIVE

The purpose of this systematic review is to determine if there is an increased risk of uterine rupture in patients with twin gestations attempting vaginal birth after cesarean (VBAC) versus planned repeat cesarean delivery (PRCD). Study Design. PubMed, Cochrane Library, and CINAHL were searched systematically. Eligible studies were prospective and retrospective studies that evaluated the incidence of uterine rupture in twin pregnancies that attempted VBAC or PRCD. Data were manually extracted from these studies, and the number of events in each group was used to calculate an odds ratio (OR) and 95% confidence interval (CI).

RESULTS

4 retrospective studies were included with a total of 7699 participants, 2305 of whom attempted VBAC and 5394 underwent PRCD. The absolute risk of uterine rupture in the VBAC and PRCD groups was 0.87% and 0.09%, respectively. The rate of uterine rupture was significantly higher in the VBAC group than in the PRCD group (OR: 9.43; CI: 3.54-25.17).

CONCLUSION

Although VBAC is associated with higher rates of uterine rupture in twin pregnancies when compared with PRCD, the absolute risk of uterine rupture is low in both groups. Depending on individual risk factors, vaginal birth may be offered as a safe option to women with twin pregnancies and a history of cesarean delivery.

VBAC: antenatal predictors of success

To determine antenatal factors that may predict successful vaginal birth after Caesarean section (VBAC), to develop a relevant antenatal scoring system and a nomogram for prediction of vaginal birth after caesarean delivery. A non recurring indication for previous Caesarean section (CS), such as breech presentation or foetal distress, is associated with a much higher successful VBAC rate than recurrent indications, such as cephalopelvic disproportion (CPD). Prior vaginal deliveries are excellent prognostic indicators of successful VBAC, especially if the vaginal delivery follows the prior CS. A low vertical uterine incision does not seem to adversely affect VBAC success rates as compared to a low transverse incision. Maternal obesity and diabetes mellitus adversely affect VBAC outcomes. Foetal macrosomia does not appear to be a contraindication to VBAC, as success rates exceeding 50% are achieved and uterine rupture rates are not increased. An inter-pregnancy interval of <24 months is not associated with a decreased success of VBAC. Success rates decrease when interval increases. Twin gestation does not preclude VBAC. Post-dates pregnancies may deliver successfully by VBAC in greater than two-thirds of cases. There are few absolute contraindications to attempted VBAC. Attempted VBAC will be successful in the majority of attempted cases.

[Predictors of birth outcomes related to women with a previous caesarean section: experience of a Motherhood Center, Bizerte]

INTRODUCTION

Caesarean section (CS) rates have been significantly increasing in recent decades. For this reason, the obstetrician must frequently decide on the most appropriate mode of delivery for mother and fetus. This study aims to describe vaginal birth after previous cesarean section (VBACs) in our obstetric practice and to identify factors significantly associated with failed VBACs.

METHODS

We conducted a population-based study among women with a history of previous cesarean delivery. The study design was retrospective, longitudinal, descriptive and analytical. The case study was conducted over a two years and three months period, from January 1, 2012 to March 31, 2014 during which we collected data from 423 medical records of patients attempting VBACs at the Maternity and Neonatology Center, Bizerte.

RESULTS

The rate of attempted VBACs was 47%. The success and the failure rates of these attempts were 82,7% and 17,3% respectively. The main factors for a poor prognosis in patients attempting VBACs were: the absence of a previous vaginal delivery (p = 0.005), a previous indication for cesarean section due to stagnation of dilatation or poor labor progress, (p 0.049 and 0.002 respectively), gestational age at delivery of = 40 weeks (p = 0.046), parity <3 (p = 0,75.10-4), Bishop score <6 at the onset of labor (p = 0,23.10-47), "active labor" duration = 6h (p = 0.002), length of labor> 8 h (p = 0.0031) and the occurrence of abnormal fetal heart rate (FHR) during labor (p = 0144.10 -9). We observed seven cases of uterine rupture (1.7%). There were no cases of maternal mortality. Total maternal morbidity rate was 9,5%. The difference in rates of maternal complications between the two groups (failed and successful attempted vaginal birth after cesarean) was not statistically significant.

CONCLUSION

Attempting vaginal birth after cesarean on the basis of good and poor prognostic factors and patient consent, contributes to the reduction in maternal and neonatal morbidity and should lead to the establishment of clear and codified Tunisian guidelines as part of a policy against unjustified iterative caesarean sections.

Factors associated with successful vaginal birth after cesarean section and outcomes in rural area of Anatolia

Successful vaginal birth after cesarean section is more comfortable than repeat emergency or elective cesarean section. Antenatal examinations are important in selection for trial of labor, while birth management can be difficult when the patients present at emergency condition. But there is an increased chance of vaginal birth with advanced cervical dilation. This study attempts to evaluate factors associated with success of vaginal birth after cesarean section and to compare the maternal and perinatal outcomes between vaginal birth after cesarean section and intrapartum cesarean section in patients who were admitted to hospital during the active or second stage of labor. A retrospective evaluation was made from the results of 127 patients. Cesarean section was performed in 57 patients; 70 attempted trial of labor. The factors associated with success of vaginal birth after cesarean section were investigated. Maternal and neonatal outcomes were compared between the groups. Vaginal birth after cesarean section was successful in 55% of cases. Advanced cervical opening, effacement, gravidity, parity, and prior vaginal delivery were factors associated with successful vaginal birth. The vaginal birth group had more complications (P<0.01), but these were minor. The rate of blood transfusion and prevalence of changes in hemoglobin level were similar in both groups (P>0.05). In this study, cervical opening, effacement, gravidity, parity, and prior vaginal delivery were important factors for successful vaginal birth after cesarean section. The patients' requests influenced outcome. Trial of labor should take into consideration the patient's preference, together with the proper setting.

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.

Prediction of scar integrity and vaginal birth after caesarean delivery

A statistically significant association with uterine rupture during a trial of labour after caesarean delivery was found in at least two studies for the following variables: inter-delivery interval (higher risk with short interval), birth weight (higher risk if 4000 g or over), induction of labour (higher risk), oxytocin dose (higher risk with higher doses), and previous vaginal delivery (lower risk). However, no clinically useful risk estimation model that includes clinical variables has been published. A thin lower uterine segment at 35-40 weeks, as measured by ultrasound in women with a caesarean hysterotomy scar, increases the risk of uterine rupture or dehiscence. No cut-off for lower uterine segment thickness, however, can be suggested because of study heterogeneity, and because prospective validation is lacking. Large caesarean hysterotomy scar defects in non-pregnant women seen at ultrasound examination increase the risk of uterine rupture or dehiscence in subsequent pregnancy, but the strength of the association is unknown. To sum up, we currently lack a method that can provide a reliable estimate of the risk of uterine rupture or dehiscence during a trial of labour in women with caesarean hysterotomy scar(s).

Delivery after prior cesarean: maternal morbidity and mortality

Nearly 1 in 3 pregnant women in the United States undergo cesarean. This trend is contrary to the national goal of decreasing cesarean delivery in low-risk women. The decline in vaginal birth after cesarean (VBAC) contributes to the continual increase in cesarean deliveries. Prior cesarean delivery is the most common indication for cesarean and accounts for more than one-third of all cesareans. The appropriate use and safety of cesarean and VBAC are of concern not only at the individual patient and clinician level but they also have far-reaching public health and policy implications at the national level.

The influence of intrapartum factors on risk of uterine rupture and successful vaginal birth after cesarean delivery

Cesarean delivery is common and increasing over time. A prior cesarean birth increases the risk of both elective and emergency cesarean births and uterine rupture in a subsequent pregnancy. A range of factors, including labor characteristics, may influence the risk of these outcomes in the next pregnancy. Intrapartum factors associated with successful vaginal birth and lower risk of uterine rupture include the spontaneous onset of labor and advanced cervical dilatation. In contrast, need for induction and augmentation of labor are both factors associated with an increased likelihood of unsuccessful vaginal birth and risk of uterine rupture.

Uterine rupture during a trial of labor after previous cesarean delivery

Uterine rupture, which involves complete separation of the uterine wall, occurs in about 1% of those attempting vaginal birth after cesarean. Because uterine rupture is one of the most significant complications of a trial of labor (TOL) after previous cesarean, identifying those at increased risk of uterine rupture is paramount to the safety of a TOL after previous cesarean birth. It seems that both antepartum demographic characteristics and intrapartum factors modify the risk of uterine rupture. The ability to reliably predict an individual's a priori risk for intrapartum uterine rupture remains a major area of investigation.

Essai de travail en cas de césarienne antérieure

OBJECTIVE

The aim of this review was to relate the evolution of obstetrical management of delivery in women who had previously undergone cesarean delivery and to search the studies supporting the choice of the mode of delivery.

MATERIAL AND METHOD

We identified relevant studies through a computer search in the Medline database.

RESULTS

After a period from 1980 to 2000 when the vaginal delivery had been increasingly recommended, a growth in the use of the planned cesarean delivery was observed. Recent studies report more evidence that uterine rupture is the result of trial of labor and that adverse perinatal outcomes are associated with uterine rupture. The risk of uterine rupture is increased with labor induction. The use of prostaglandins appears to be implicated in a significant increase of uterine rupture, and subsequently might be contraindicated in this situation. The use of oxytocin induced labor appears to increase the risk of uterine rupture. However, the level of adverse perinatal outcomes is low. The choice of the mode of delivery should take into account the likelihood of a further pregnancy, due to the increased risk of placental pathologic conditions depending on the number of repeated cesarean sections.

CONCLUSION

An optimal decision for the mode of delivery should be shared with the pregnant women and all these factors should be taken into consideration.

The MFMU Cesarean Registry: factors affecting the success of trial of labor after previous cesarean delivery

OBJECTIVE

The purpose of this study was to determine which factors influence the likelihood of successful trial of labor (TOL) after 1 previous cesarean delivery (CD).

STUDY DESIGN

We performed a multicenter 4-year prospective observational study (1999-2002) of all women with previous CD undergoing TOL. Women with term singleton pregnancies with 1 previous low transverse CD or unknown incision were included for analysis.

RESULTS

Fourteen thousand five hundred twenty-nine women underwent TOL, with 10,690 (73.6%) achieving successful VBAC. Women with previous vaginal birth had an 86.6% success rate compared with 60.9% in women without such a history (odds ratio [OR] 4.2; 95% CI 3.8-4.5; P < .001). TOL success rates were affected by previous indication for CD, need for induction or augmentation, cervical dilation on admission, birth weight, race, and maternal body mass index. Multivariate logistic regression analysis identified as predictive of TOL success: previous vaginal delivery (OR 3.9; 95% CI 3.6-4.3), previous indication not being dystocia (CPD/FTP) (OR 1.7; 95% CI 1.5-1.8), spontaneous labor (OR 1.6; 95% CI 1.5-1.8), birth weight <4000 g (OR 2.0; 95% CI 1.8-2.3), and Caucasian race (OR 1.8, 95% CI 1.6-1.9) (all P < .001). The overall TOL success rate in obese women (BMI > or = 30) was lower (68.4%) than in nonobese women (79.6%) (P < .001), and when combined with induction and lack of previous vaginal delivery, successful VBAC occurred in only 44.2% of cases.

CONCLUSION

Previous vaginal delivery including previous VBAC is the greatest predictor for successful TOL. Previous indication as dystocia, need for labor induction, or a maternal BMI > or = 30 significantly lowers success rates.

Does the maxim "once a Caesarean, always a Caesarean" still hold true?

Ugwumadu discusses a new tool, reported in PLoS Medicine, that can help to predict the risks of Caesarean section and uterine rupture in women attempting vaginal birth after prior Caesarean section.

Trial of labor in patients with a previous cesarean section: does maternal age influence the outcome?

OBJECTIVE

This study was undertaken to evaluate the effect of maternal age on the rate of vaginal delivery and the rate of uterine rupture in patients undergoing a trial of labor (TOL) after a prior cesarean delivery.

STUDY DESIGN

A cohort study of all women with a live singleton fetus undergoing a TOL after a previous low-transverse cesarean delivery was performed between 1988 and 2002 in a tertiary care center. Patients were divided into 3 groups according to maternal age: less than 30 years old, 30 to 34 years old, and 35 years or older. Women with no prior vaginal delivery and with at least 1 prior vaginal delivery were analyzed separately. The rate of vaginal delivery and the rate of symptomatic uterine rupture were calculated. Multivariate logistic regression analyses were performed to adjust for potential confounding variables.

RESULTS

Of the 2493 patients who met the study criteria, there were 1750 women without a prior vaginal delivery (659, 721, and 370, respectively) and 743 women with a prior vaginal delivery (199, 327, and 217, respectively). The rate of uterine rupture was comparable between the groups (2.0%, 1.1%, 1.4%, P=.404 and 0%, 0.3%, 0.9%, P=.312). Successful vaginal delivery was inversely related to maternal age (71.9%, 70.7%, 65.1%, P=.063, and 91.5%, 91.1%, 82.9%, P=.005). After adjusting for confounding variables, maternal age equal to or greater than 35 years old was associated with a lower rate of successful vaginal delivery in patients without prior vaginal delivery (odds ratio [OR] 0.73, 95% CI: 0.56-0.94), and in patients with a prior vaginal delivery (OR: 0.47, 95% CI: 0.29-0.74).

CONCLUSION

Patients who are 35 years or older are more prone to have a failed TOL after a prior cesarean delivery.

Predicting vaginal birth after cesarean delivery: a review of prognostic factors and screening tools

OBJECTIVE

Our purpose was to identify the factors associated with vaginal delivery after trial of labor in patients with a prior cesarean and to evaluate the effectiveness of existing screening tools.

STUDY DESIGN

Studies were identified through MEDLINE and HealthSTAR (1980-2002), reference list reviews, and suggestions of national experts.

RESULTS

Thirteen of the 100 eligible studies provided fair to good quality evidence for the predictive nature of 12 factors. Two of the six screening tools were considered promising and demonstrated reproducibility through validation studies.

CONCLUSIONS

There is little high-quality data to guide clinical decisions regarding which women are likely to have a successful trial of labor. Although we identified two validated screening tools that may be reasonable for practitioners to use, further development is needed to deliver them in a user-friendly manner and further research is needed to determine the clinical setting in which they are most useful. Conducting high-quality research on the factors that delineate women who are at higher likelihood of vaginal delivery without complications and developing accurate user-friendly screening tools to integrate these data should be a national research priority.

Extrusion of fetus into the abdominal cavity following complete rupture of uterus: a case report

A gravida 10 para 9, after one Cesarean section (CS) followed by four vaginal deliveries was admitted at term without uterine contractions complaining of abdominal pain. The type of uterine scar was unknown. Severe bradycardia was observed at admission and an emergency Cesarean section was performed. A complete uterine rupture was revealed, the fetus in intact membranes and placenta were found in the abdominal cavity.

Management of previous cesarean section

PURPOSE OF REVIEW

The management of cesarean sections causes much controversy among healthcare providers, patients, and insurers. A trial of vaginal birth after previous cesarean is reported to be a safe and practical method to reduce the rate of cesarean sections. The popularity of vaginal birth after previous cesarean has increased over the past two decades, but rates have recently started to decline again. This review will evaluate recent literature that might be responsible for this reversal in trend.

RECENT FINDINGS

Earlier studies on previous cesarean section pregnancies focused primarily on the success rate of vaginal birth after previous cesarean, which is reported to be 60-80%. Recent large, retrospective, population-based cohort studies examined the maternal and neonatal safety of trial of labour compared with elective repeat cesarean delivery, and confirmed that the risks of uterine rupture and neonatal mortality were significantly increased after trial of labour, particularly when induced with prostaglandins. However, the absolute risk of adverse events remains small. The maternal and neonatal morbidity risk increases when vaginal birth after previous cesarean attempts fails, which emphasizes the importance of careful case selection.

SUMMARY

Recent studies highlighted the risks of attempted vaginal birth after previous cesareans, especially when trials fail, but have not addressed the long-term risks of an elective repeat cesarean delivery. The assessment of treatment risks by observational studies is subject to bias, because the different treatment groups may not be comparable at the outset. In the absence of better data, the counselling of such women must currently be based on this evidence.