Vaginal birth after cesarean (VBAC) attempt in twin pregnancies: is it safe?

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.

Induction of labor in twin pregnancy in patients with a previous cesarean delivery

BACKGROUND

Trial of labor after cesarean delivery (TOLAC) in twin gestations has been associated with decreased rates of successful vaginal delivery compared to singleton pregnancies, with mixed results regarding maternal and neonatal morbidity. However, induction of labor (IOL) in this unique population has not yet been fully evaluated.

OBJECTIVE

To assess success rates and maternal and neonatal outcomes in women with a twin gestation and a previous cesarean delivery undergoing IOL.

METHODS

A retrospective cohort study including women with a twin gestation and one previous cesarean delivery undergoing a trial of labor between the years 2009-2020. Patients requiring IOL were compared to those with a spontaneous onset of labor.

RESULTS

There were 53 patients who met the inclusion criteria: 31 had a spontaneous onset of labor (58%) and 22 required an IOL. Baseline characteristics were comparable between the groups apart from a history of labor arrest which was more common in the IOL group (40.9% vs. 9.6%, P = 0.006). A successful vaginal delivery occurred in all (100%) women with a spontaneous labor compared to 81% in the IOL group (p = 0.02). Secondary outcomes were comparable. A history of no previous vaginal delivery, maternal obesity, and IOL were associated with TOLAC failure.

CONCLUSIONS

IOL after cesarean delivery in twin gestation is associated with an increased risk of TOLAC failure compared to spontaneous onset of labor. However, no adverse neonatal or maternal outcomes were found. IOL in this high-risk population is feasible but patients should be counseled about the lower rate of success.

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.

Factors Associated with Failed Trial of Labor after Cesarean, among Women with Twin Gestation-A Multicenter Retrospective Cohort Study

Objective: Twin trial of labor after a cesarean section (TOLAC) is associated with a lower success rate of vaginal delivery than singleton TOLAC, and a higher rate of adverse outcomes in comparison to an elective repeat cesarean delivery. This study aims to investigate the factors associated with failed TOLAC, among women with twin gestation. Study design: A multicenter retrospective cohort study was undertaken. All women with twin pregnancies attempting a trial of labor after a previous cesarean in two university-affiliated obstetrical centers, between 2005 and 2021 were included. The study population included women with a twin gestation where twin A presented in the vertex position, a single previous low segment transverse section, and those who were eligible for a vaginal delivery. Labor, maternal, and neonatal characteristics were compared. A univariate analysis was undertaken, followed by multivariate analysis (aORs; [95% CI]). Results: A total of 160 women attempting a twin TOLAC were included. Vaginal birth after cesarean was achieved in 86.3% of these cases. Assisted reproductive technology (ART), the lack of oxytocin use for augmentation during labor, the lack of epidural analgesia, and preterm birth before 34, 32, and 28 gestational weeks were all found to be associated with failed TOLAC. In the multivariate analysis, cervical dilation on admission (aOR 0.6 [0.40−0.82], p < 0.01), no use of oxytocin (aOR 5.2 [1.36−19.73], p = 0.02), gestational age at delivery (aOR 0.8 [0.65−1.00], p = 0.047) and lack of epidural analgesia (aOR 4.5 [1.01−20.16], p = 0.049), were all found to be significantly associated with failed TOLAC. Conclusion: In the investigated population of women with twins undergoing TOLAC, the use of epidural analgesia, the use of oxytocin and increased cervical dilation to the delivery room are associated with a higher rate of vaginal delivery, and may reduce the risk of repeat cesarean delivery.

Trial of labor of vertex-nonvertex twins following a previous cesarean delivery

BACKGROUND

Maternal and neonatal outcomes of trial of labor after cesarean delivery of twins are similar to those of singleton trials of labor after cesarean delivery. However, previous studies did not stratify outcomes by second-twin presentation on admission to labor.

OBJECTIVE

To examine maternal and neonatal outcomes following trial of labor after cesarean delivery in twins with vertex-nonvertex presentation.

STUDY DESIGN

A retrospective multicenter study was conducted including data on deliveries occurring between the years 2005 and 2020. We included trials of labor after a previous cesarean delivery (at ≥32^0/7 weeks' gestation) of twin gestations with a vertex-presenting first twin on admission to labor. The exposed group was defined as deliveries with a nonvertex second twin at admission to labor, whereas the comparison group included deliveries with a vertex second twin at admission. Only parturients who attempted vaginal delivery were included. Cases of prelabor fetal death of either twin or major fetal anomalies were excluded. The primary outcome was uterine rupture.

RESULTS

A total of 236 twin trials of labor after cesarean delivery were included, of which 128 involved nonvertex second twins and 108 a second vertex twin. Uterine rupture rates were comparable between the groups (1/128 [0.9%] vs 1/108 [0.8%]; P=1.000). Successful trial of labor after cesarean delivery of both twins occurred in 76.6% of the exposed group vs 81.5% of the comparison group, whereas cesarean delivery of both twins was performed in 21.9% of the exposed group vs 17.6% of the comparison group (P=.418; odds ratio, 1.32; confidence interval, 0.7-2.5). Two cases of cesarean delivery of the second twin occurred in the exposed group and 1 in the comparison group (1.6% vs 0.9%, respectively, P=1.000). There was no difference between the groups in maternal outcomes, including rates of postpartum hemorrhage, blood transfusion, placental abruption, thromboembolic events, and maternal fever. Neonatal outcomes were also comparable between the groups, including rates of intensive care admission and low (≤7) 5-minute Apgar scores.

CONCLUSION

Our data show that trial of labor after cesarean delivery of noncephalic second twins holds favorable maternal and neonatal outcomes, comparable with those of vertex-vertex trials of labor after cesarean delivery. Second-twin noncephalic presentation should not discourage parturients and caregivers from considering trial of labor after cesarean delivery if desired.

Mode of delivery in multiple pregnancies

The mode of delivery in multiple pregnancies has been subject to vigorous debates during the last few decades. Although observational and retrospective data were accumulated, it was not until the publication of the Twin Birth Study that evidence-based recommendations could emerge. However, although some of the most pressing questions were answered by the Twin Birth Study, other questions were left outside the scope of the study. The questions were of great interest and included the following topics: the impact of gestational age, the influence of chorionicity, and the generalizability of the results for women with a previous uterine scar. The current evidence supported a trial of labor in dichorionic-diamniotic or monochorionic-diamniotic twin pregnancies in which the first twin is in cephalic presentation at ≥32 weeks' gestation. Dichorionic-diamniotic, monochorionic-diamniotic, and monochorionic-monoamniotic twins should be delivered at 37 0/7 to 38 0/7, 36 0/7 to 37 0/7, and 32 0/7 to 34 0/7 weeks' gestation, respectively. Breech extraction done by a competent healthcare provider seemed to offer a higher chance of successful vaginal delivery of the second twin than the external cephalic version. The current data did not allow for a clear recommendation regarding the mode of delivery in very preterm birth of low birthweight twins, but most studies did not demonstrate a clear benefit of cesarean delivery vs trial of labor. Furthermore, a trial of labor seemed safe in women with a previous cesarean delivery. Cesarean delivery is likely beneficial for twin pregnancies with the first twin in breech presentation, monochorionic-monoamniotic twins, and higher-order multiple pregnancies. In all multiple pregnancies, delivery should be performed by an experienced practitioner competent in multiple pregnancy deliveries.

Multifetal Gestations: Twin, Triplet, and Higher-Order Multifetal Pregnancies: ACOG Practice Bulletin, Number 231

The incidence of multifetal gestations in the United States has increased dramatically over the past several decades. For example, the rate of twin births increased 76% between 1980 and 2009, from 18.9 to 33.3 per 1,000 births (1). However, after more than three decades of increases, the twin birth rate declined 4% during 2014-2018 to 32.6 twins per 1,000 total births in 2018 (2). The rate of triplet and higher-order multifetal gestations increased more than 400% during the 1980s and 1990s, peaking at 193.5 per 100,000 births in 1998, followed by a modest decrease to 153.4 per 100,000 births by 2009 (3). The triplet and higher-order multiple birth rate was 93.0 per 100,000 births for 2018, an 8% decline from 2017 (101.6) and a 52% decline from the 1998 peak (193.5) (4). The long-term changes in the incidence of multifetal gestations has been attributed to two main factors: 1) a shift toward an older maternal age at conception, when multifetal gestations are more likely to occur naturally, and 2) an increased use of assisted reproductive technology (ART), which is more likely to result in a multifetal gestation (5). A number of perinatal complications are increased with multiple gestations, including fetal anomalies, preeclampsia, and gestational diabetes. One of the most consequential complications encountered with multifetal gestations is preterm birth and the resultant infant morbidity and mortality. Although multiple interventions have been evaluated in the hope of prolonging these gestations and improving outcomes, none has had a substantial effect. The purpose of this document is to review the issues and complications associated with twin, triplet, and higher-order multifetal gestations and present an evidence-based approach to management.

Twin TOLAC is an independent risk factor for adverse maternal and neonatal outcome

PURPOSE

To determine factors associated with a successful twin trial of labor after Cesarean delivery (TOLAC).

METHODS

A retrospective cohort study was conducted at a single medical center in a population highly motivated for TOLAC (> 80%). The effect of maternal demographic and obstetric characteristics on the likelihood of twin TOLAC success was analyzed. Maternal complications and combined adverse outcome (uterine rupture, Apgar < 7 at 5 min, and umbilical cord pH < 7.1) were compared between singleton and twin TOLAC groups.

RESULTS

Ninety-five women with a twin gestation and one previous Cesarean delivery comprised the study group. Five thousand seven hundred and three women with a singleton gestation and one previous Cesarean delivery comprised the control group. 30.5% and 83% of women with twin and singleton gestation, respectively, underwent a trial of labor. Women in the twin TOLAC group were significantly less likely to succeed and less likely to have a spontaneous unassisted vaginal delivery compared to women in the singleton TOLAC group. Maternal age less than 35 years, parity greater than two, and at least one previous VBAC increased the likelihood of TOLAC success. Statistically significant differences were found between the twin TOLAC and the singleton TOLAC group for uterine rupture, maternal complications, and for combined adverse outcome.

CONCLUSIONS

Twin TOLAC is not common, even in parturients highly motivated for TOLAC. Our results demonstrate that even in a selected population, women undergoing twin TOLAC are less likely to have a successful spontaneous vaginal delivery and have a higher risk for uterine rupture, maternal complications, and combined adverse perinatal outcome than women undergoing TOLAC with a singleton gestation. Demographic and obstetric risk factors were identified which can aid the attending obstetrician in the counseling of these challenging cases.

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.

Cesarean scar thickness in non-pregnant women as a risk factor for uterine rupture

Introduction: Whether there is an association between residual myometrial thickness (RMT) after cesarean section (CS) and the risk of uterine rupture (UR) or uterine scar dehiscence at the subsequent delivery has been sparsely investigated.Materials and methods: Our cohort included 149 women with a first CS in whom we measured RMT by transvaginal ultrasonography 6-15 months after their delivery. We did a follow-up study on delivery outcomes in the women's subsequent births. The exposure was scar measurements in the non-pregnant uterus, and the primary outcome was a diagnosis of UR or dehiscence. We calculated likelihood ratios (LRs) with 95% confidence intervals of having UR or dehiscence with a thin RMT (<3 mm).Results: Among the 149 women, 39 had a repeat CS (14 scheduled and 25 unscheduled procedures), and within these, we found one woman with UR and five women with uterine dehiscence. The proportion of women with a thin RMT was significantly higher among cases (4/6) than in controls (4/33); the LR was 5.5 (95% CI 1.9-16.2).Conclusions: The results suggest a significant association between a thin RMT as measured by transvaginal ultrasonography in the non-pregnant uterus after a first scheduled CS and the risk of UR or dehiscence at a subsequent delivery.

ACOG Practice Bulletin No. 205: Vaginal Birth After Cesarean Delivery

Trial of labor after cesarean delivery (TOLAC) refers to a planned attempt to deliver vaginally by a woman who has had a previous cesarean delivery, regardless of the outcome. This method provides women who desire a vaginal delivery the possibility of achieving that goal-a vaginal birth after cesarean delivery (VBAC). In addition to fulfilling a patient's preference for vaginal delivery, at an individual level, VBAC is associated with decreased maternal morbidity and a decreased risk of complications in future pregnancies as well as a decrease in the overall cesarean delivery rate at the population level (). However, although TOLAC is appropriate for many women, several factors increase the likelihood of a failed trial of labor, which in turn is associated with increased maternal and perinatal morbidity when compared with a successful trial of labor (ie, VBAC) and elective repeat cesarean delivery (). Therefore, assessing the likelihood of VBAC as well as the individual risks is important when determining who is an appropriate candidate for TOLAC. Thus, the purpose of this document is to review the risks and benefits of TOLAC in various clinical situations and to provide practical guidelines for counseling and management of patients who will attempt to give birth vaginally after a previous cesarean delivery.

Trial of labor after cesarean delivery in twin gestations: systematic review and meta-analysis

BACKGROUND

Trial of labor after cesarean is offered as a routine option for singleton gestations with previous cesarean delivery. However, adequate data are not available to determine whether the approach is equally valid in women with twin gestation.

OBJECTIVE

This systematic review and meta-analysis aimed to assess maternal morbidities associated with trial of labor after cesarean delivery in twin gestations.

STUDY DESIGN

Electronic databases were searched for cohort studies and randomized controlled trials evaluating the association between trial of labor after cesarean delivery in twin gestations and pregnancy outcomes. Maternal mortality and severe morbidities, such as uterine rupture and hysterectomy, were compared between women who had trial of labor and women who had a planned repeat cesarean delivery. Pooled odds ratios were calculated using a random-effects model. Additional analyses were performed to compare trial of labor after cesarean outcomes in singleton and twin gestations.

RESULTS

Eleven cohort studies including a total of 8209 twin gestations with previous cesarean delivery were included in the present study. Of these gestations, 2484 were intended for planned vaginal birth and 5725 were intended for planned repeat cesarean delivery. The rate of uterine rupture in twin gestations was higher in the trial of labor after cesarean group than the elective cesarean group (odds ratio, 10.09, 95% confidence interval, 4.30-23.69, I² = 68%). However, no statistically significant difference was found in the rate of uterine rupture between twin and single gestations attempting trial of labor after cesarean delivery (odds ratio, 1.34, 95% confidence interval, 0.54-3.31, I² = 0%). Women who attempted a trial of labor after cesarean delivery with twins did not have an increased risk of uterine scar dehiscence, hemorrhage, blood transfusion, or neonatal morbidity and mortality compared with elective repeat cesarean delivery. Patients with twins had similar rates of successful vaginal delivery as patients with singletons (odds ratio, 0.85, 95% confidence interval, 0.61-1.18, I² = 36%).

CONCLUSION

This meta-analysis demonstrates that, although trial of labor with twins after previous cesarean delivery is associated with higher rates of uterine rupture compared with elective cesarean delivery, pregnancy outcomes and success rates are similar to a trial of labor after previous cesarean delivery in singleton gestations. Planned vaginal birth for women with twin gestation and previous cesarean delivery may be a safe alternative to a planned repeat cesarean.

Practice Bulletin No. 184: Vaginal Birth After Cesarean Delivery

Trial of labor after cesarean delivery (TOLAC) refers to a planned attempt to deliver vaginally by a woman who has had a previous cesarean delivery, regardless of the outcome. This method provides women who desire a vaginal delivery the possibility of achieving that goal-a vaginal birth after cesarean delivery (VBAC). In addition to fulfilling a patient's preference for vaginal delivery, at an individual level, VBAC is associated with decreased maternal morbidity and a decreased risk of complications in future pregnancies as well as a decrease in the overall cesarean delivery rate at the population level (1-3). However, although TOLAC is appropriate for many women, several factors increase the likelihood of a failed trial of labor, which in turn is associated with increased maternal and perinatal morbidity when compared with a successful trial of labor (ie, VBAC) and elective repeat cesarean delivery (4-6). Therefore, assessing the likelihood of VBAC as well as the individual risks is important when determining who is an appropriate candidate for TOLAC. Thus, the purpose of this document is to review the risks and benefits of TOLAC in various clinical situations and to provide practical guidelines for counseling and management of patients who will attempt to give birth vaginally after a previous cesarean delivery.

Contemporary epidemiology and novel predictors of uterine rupture: a nationwide population-based study

PURPOSE

In spite of several policies aiming to decrease cesarean rates and related complications such as uterine rupture, data show that uterine rupture and associated morbidity are increasing along the years. Whether previously unidentified risk factors are currently playing an important role on these trends is unknown. We analyze current risks of uterine rupture and main preceding factors from more recent years compared to former data.

METHODS

All uterine rupture cases in the US from 2011-2012 were selected, with matched non-uterine rupture cases selected as controls. Variables considered for analysis included demographics, maternal morbidity, and obstetric complications. Likelihood forward selection was used to identify main risk factors of uterine rupture. Medians of main factors identified were used to simulate groups at risk and calculate odds ratios of uterine rupture.

RESULTS

From ~8 million births, 1925 presented uterine rupture. In patients with no prior cesarean delivery, multiple gestation, chronic hypertension and chorioamnionitis presented the highest odds of uterine rupture, with the combination of these factors increasing the odds of rupture 59 times (~1%). In women with prior cesarean delivery, induction/augmentation and chorioamnionitis were the most significant predictors, with the combination increasing the odds 33 times (~3%).

CONCLUSIONS

Despite policies implemented and changes in clinical practice, uterine rupture remains an important issue. Previously unidentified risk factors are playing now an important role, information that should be considered during patient counseling and clinical practice. Combinations of some of these factors may increase the risk of uterine rupture significantly enough to modify clinical care.

Contemporary analysis of maternal and neonatal morbidity after uterine rupture: A nationwide population-based study

AIM

Uterine rupture is a rare but feared perinatal event. Despite abundant research and changes to guidelines implemented to reduce this complication, evaluation of whether uterine rupture still engenders significant maternal/neonatal morbidity has not been conducted. We analyzed recent cases of maternal/neonatal morbidity after uterine rupture.

METHODS

Deliveries complicated by uterine rupture from 2011 to 2012 in the United States were selected. Comparison cases without uterine rupture were used as controls. Measures of maternal/neonatal complications were compared with χ² test, and relative risks were calculated. Logistic regression was used to identify the most significant complications. P < 0.05 indicated statistical significance.

RESULTS

From 7 922 016 births, 1925 cases of uterine rupture and 3765 controls were identified. Regression models retained four maternal outcomes; blood transfusion was the most common (~15%) and unplanned hysterectomy had the highest odds (~97-fold). For newborns, the model retained three measures of morbidity; neonatal intensive care unit admission was the most common (~35%) and seizures had the highest odds (~20-fold).

CONCLUSIONS

Despite efforts to reduce complications, mothers remain at significant risk of unplanned hysterectomy and intensive care unit admission. Neonates are at sizeable risk for neonatal intensive care unit admission and seizures, recognized markers of long-term neurobehavioral abnormality. Uterine rupture remains a major risk for mothers and babies.

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).

Trial of labor after cesarean section in twin pregnancies: maternal and neonatal safety

OBJECTIVE

To assess maternal and perinatal morbidity in patients undergoing a trial of labor after cesarean section (TOLAC) in twin gestations.

METHODS

A retrospective study including all twin pregnancies with a single prior cesarean section was performed. Stratified analysis using a multiple logistic regression model was performed to control for confounders. Patients who had a clear medical indication for a cesarean section (i.e. previous corporeal cesarean section, breech or transverse presentation, placenta previa, placental abruption, and herpes infection) were excluded from the analysis.

RESULTS

During the years 1988-2007, 134 patients met the inclusion criteria. Of these, 25 patients underwent a trial of labor and the remaining 109 underwent a repeat cesarean delivery. There were no cases of uterine rupture, maternal mortality, or peripartum fever in our population. Higher rates of perinatal mortality were noted in patients undergoing a trial of labor (8% vs. 1.8%, p = 0.042, OR = 4.652, 95% CI = 1.122-19.286). However, a trial of labor was not found to be an independent risk factor for perinatal mortality after controlling for confounders such as gestational age, ethnicity, and fetal malformations (adjusted OR = 1.07, 95% CI = 0.07-15.95, p = 0.95).

CONCLUSIONS

A TOLAC is not associated with an increased risk for maternal morbidity, including uterine rupture. Nevertheless, in our population TOLAC was noted as a risk factor for perinatal mortality, although residual confounding cannot be excluded. Further prospective randomized studies should evaluate the safety of TOLAC in twin gestations to establish appropriate guidelines.

Trends and patterns of vaginal birth after cesarean availability in the United States

A review of the literature and analysis of the National Inpatient Sample Database was performed to describe the trends in vaginal birth after cesarean availability in the United States and the factors associated with changing use. Vaginal birth after cesarean increased after the first National Institutes of Health Consensus Conference on Cesarean Childbirth in 1981. It increased from 3% to a maximum rate of 28.3% in 1996. Despite studies reporting stable success rates of approximately 70% and low complication rates (<1%), concerns about patient safety and physician liability have led to more restrictive policies and a decrease in vaginal birth after cesarean use. The current rate is approximately 8.5%, and decreased rates have been noted for all age and ethnic groups. There is decreased use of vaginal birth after cesarean as the result of concerns about patient safety and physician liability, which has resulted in decreased availability.

Birth after previous cesarean delivery: short-term maternal outcomes

An estimated 40% of the 1.3 million cesarean deliveries performed each year in the United States are repeat procedures. The appropriate clinical management approach for women with previous cesarean delivery remains challenging because options are limited. The risks and benefits of clinical management choices in the woman's health need to be quantified. Thus, we discuss the available published scientific data on (1) the short-term maternal outcomes of trial of labor after cesarean and elective repeat cesarean delivery, (2) the differences between outcomes for both, (3) the important factors that influence these outcomes, and (4) successful vs. unsuccessful vaginal birth after cesarean. For women with a previous cesarean delivery, a successful trial of labor offers several distinct, consistently reproducible advantages compared with elective repeat cesarean delivery, including fewer hysterectomies, fewer thromboembolic events, lower blood transfusion rates, and shorter hospital stay. However, when trial of labor after cesarean fails, emergency cesarean is associated with increased uterine rupture, hysterectomy, operative injury, blood transfusion, endometritis, and longer hospital stay. Care of women with a history of previous cesarean delivery involves a confluence of interactions between medical and nonmedical factors; however, the most important determinants of the short-term outcomes among these women are likely individualized counseling, accurate clinical diagnoses, and careful management during a trial of labor. We recommend a randomized controlled trial among women undergoing a TOLAC and a longitudinal cohort study among women with previous cesarean to evaluate adverse outcomes, with focused attention on both mother and the infant.

Delivery after previous cesarean: short-term perinatal outcomes

Women must often choose between a vaginal birth after previous cesarean and elective repeat cesarean delivery. Short-term risks of vaginal birth after cesarean can be potentially catastrophic in the setting of uterine rupture. Although randomized controlled trials comparing these 2 modes of delivery are lacking, observational studies suggest an increased risk of perinatal mortality and hypoxic-ischemic encephalopathy in infants whose mothers undergo a trial of labor. These rare risks compete with more common, albeit less severe, short-term risks associated with elective repeat cesarean delivery, with a particular emphasis on increased respiratory morbidities. Further studies are needed to identify potential strategies to improve perinatal outcomes and help guide physicians and patients in choosing optimal methods of delivery.

Do vaginal birth after cesarean outcomes differ based on hospital setting?

OBJECTIVE

The objective of the study was to test the null hypothesis that outcomes of vaginal birth after cesarean (VBAC) do not differ on the basis of the hospital setting.

STUDY DESIGN

The study was a retrospective cohort study of women who were offered VBAC in 17 hospitals from 1996 to 2000. VBAC attempts occurring in hospitals with and without obstetrics-gynecology residency programs were compared, as were outcomes from university and community hospitals. Bivariate and multivariate logistic regression analyses assessed the association between hospital setting and VBAC outcomes.

RESULTS

Of 25,065 women with 1 or more prior cesareans, the VBAC attempt rate was 56.1% at hospitals with obstetrics-gynecology residencies, 51.3% at hospitals without obstetrics-gynecology residencies, 61% at university hospitals, and 50.4% at community hospitals. The occurrence of failed VBAC, blood transfusion, or composite adverse outcome did not differ by hospital setting. There was a significant increase in the uterine rupture rate at community (1.2%) vs university hospitals (0.6%), but the absolute risk remained low.

CONCLUSION

The rate of VBAC-associated complications is low, independent of hospital setting.

Intrapartum management of twin gestations

A trial of labor and vaginal delivery are usually indicated in vertex-vertex twins. For vertex-nonvertex twins, vaginal birth is preferred, with the second twin being delivered by breech extraction, unless it is significantly larger than the first. Cesarean delivery is indicated if the first twin is nonvertex and for all cases of monoamniotic or potentially viable conjoined twins. There is a limited role for trial of labor after cesarean delivery in twin gestations. In my opinion, combined vaginal-cesarean birth is the riskiest method for mother and infants and should be avoided if possible.

Vaginal Birth After Cesarean Delivery: Evidence-based Practice

Given the high national rate of cesarean delivery in current obstetric practice, patients considering vaginal birth after cesarean (VBAC) in subsequent pregnancies are frequently encountered. A recently growing body of literature on VBAC has produced concrete evidence to define the VBAC-associated risks and identify factors influencing success. An evidence-based approach can guide practitioners and patients through the complex counseling, decision-making, and management issues when considering VBAC delivery.

Is vaginal birth after cesarean (VBAC) or elective repeat cesarean safer in women with a prior vaginal delivery?

OBJECTIVE

This study was undertaken to determine whether vaginal birth after cesarean (VBAC) or elective repeat cesarean delivery is safer overall for a woman with a prior vaginal delivery.

STUDY DESIGN

This retrospective cohort study of pregnant women from 1996 to 2000 who had a prior cesarean delivery, was conducted in 17 centers. Trained nurses extracted historical and maternal outcome data on subjects by using standardized tools. This planned secondary analysis examined the subcohort that had also previously undergone a vaginal delivery, comparing those who underwent a VBAC trial with those who elected to have a repeat cesarean delivery. Outcomes included uterine rupture, bladder injury, fever, transfusion and a composite (uterine rupture, bladder injury, and artery laceration). We performed bivariate and multivariable analyses.

RESULTS

Of 6619 patients with a prior cesarean delivery who had also had a prior vaginal delivery, 5041 patients attempted a VBAC delivery and 1578 had an elective cesarean delivery. Although there was no significant difference in uterine rupture or bladder injury between the two groups, women who underwent a VBAC attempt were less likely to experience the composite adverse maternal outcome, have a fever, or require a transfusion.

CONCLUSION

Among VBAC candidates who have had a prior vaginal delivery, those who attempt a VBAC trial have decreased risk for overall major maternal morbidities, as well as maternal fever and transfusion requirement compared with women who elect repeat cesarean delivery. Physicians should make this more favorable benefit-risk ratio explicit when counseling this patient subpopulation on a trial of labor.

Vaginal birth after cesarean delivery in twin gestations: a large, nationwide sample of deliveries

OBJECTIVE

The purpose of this study was to assess the maternal morbidity associated with attempted vaginal birth after cesarean (VBAC) in twin gestations using a large, nationwide sample of deliveries.

STUDY DESIGN

Data for this study were obtained from an administrative dataset, the Nationwide Inpatient Sample, a representative sample of discharges from non-Federal hospitals, for the years 1993 to 2002. Patients admitted nonemergently for the delivery of twin gestations who had a history of previous cesarean delivery were selected. Patients that either delivered vaginally or who had discharge codes that indicated labor before cesarean delivery were defined as the trial of labor group, while patients who had a cesarean delivery without discharge codes that indicated labor were defined as the elective cesarean group. Various complications of delivery were analyzed for each group.

RESULTS

We identified 4705 women who underwent an elective cesarean delivery and 1850 women who underwent a trial of labor. For women who had a trial of labor, 836 (45.2%) delivered vaginally. The rate of uterine rupture was higher in the trial of labor group than in the elective cesarean group (0.9% vs 0.1%, P < .001), and the rate of wound complications was lower (0.6% vs 1.3%, P < .02). The rates of other complications including hysterectomy, transfusion, major postpartum infection, thromboembolism, uterine dehiscence, and pelvic hematoma were not significantly different between the 2 groups.

CONCLUSION

Our study showed a significantly higher rate of uterine rupture in the trial of labor group that is similar to the rates reported for trial of labor after cesarean in singleton pregnancies.