IJG-07906; No of Pages 3 International Journal of Gynecology and Obstetrics xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
International Journal of Gynecology and Obstetrics journal homepage: www.elsevier.com/locate/ijgo
CLINICAL ARTICLE
Predicting why women have elective repeat cesarean deliveries and predictors of successful vaginal birth after cesarean Fionnuala Mone a,⁎, Conor Harrity b, Brenda Toner b, Aine Mcnally b, Beverley Adams c, Aoife Currie c a b c
Department of Obstetrics and Gynaecology, Medicine and Medical Science, University College Dublin, Ireland Department of Obstetrics, Altnagelvin Area Hospital, Londonderry, UK Department of Obstetrics, Craigavon Area Hospital, Craigavon, UK
a r t i c l e
i n f o
Article history: Received 26 August 2013 Received in revised form 16 December 2013 Accepted 13 March 2014 Keywords: Elective repeat cesarean Predictors Trial of labor after cesarean Vaginal birth after cesarean
a b s t r a c t Objective: To compare the characteristics of women who select elective repeat cesarean rather than trial of labor after cesarean (TOLAC) for delivery, and to determine individual predictors for success and failure within a TOLAC group and observe differences in maternal and neonatal morbidity. Methods: The present descriptive, retrospective, observational study was performed in a regional obstetric unit in the United Kingdom. Data were collected from the Northern Ireland Maternity System database on all women who gave birth between April 2010 and April 2012, and had a previous cesarean delivery, and statistical analysis was performed. Results: In total, 893 patients were included in the study: 385 underwent TOLAC and 493 underwent elective repeat cesarean. On comparison, women in the elective repeat cesarean group had a shorter inter-delivery interval and fewer had had a previous vaginal delivery (P b 0.005). Predictors for success in the TOLAC group included previous vaginal delivery and a longer inter-delivery interval (P b 0.05). Successful vaginal birth after cesarean (VBAC) did not have higher rates of maternal morbidity. Conclusion: The majority of patients (56%) chose elective repeat cesarean rather than TOLAC, which has long-term implications both clinically and financially. A validated prediction model might improve patient counseling and identify women with a high likelihood of successful VBAC. © 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
1. Introduction Rising rates of cesarean delivery are an issue of international concern. Rates of cesarean delivery are increasing in the United Kingdom, where the average rate is 25% [1]. Elective repeat cesarean accounts for a significant proportion of the overall rate of cesarean delivery [1, 2]. This has implications not only economically, but also in terms of maternal and neonatal morbidity. Studies have demonstrated that neonates of mothers who undergo elective repeat cesarean can be at greater risk of respiratory morbidity [3,4]. Maternal complications associated with elective repeat cesarean include placenta accreta, visceral injury, intensive care unit admission, hysterectomy, blood transfusion, and a longer duration of hospital stay [5]. Vaginal birth after cesarean (VBAC) is not without its own risks, which include uterine rupture [6], endometritis, and the need for blood transfusion [7]. Awareness of these complications, combined with maternal anxiety about requiring an emergency cesarean, may be the reason that uptake of trial of labor after cesarean (TOLAC) is low [8].
⁎ Corresponding author at: Department of Medicine and Medical Science, University College Dublin, National Maternity Hospital, Holles St, Dublin 2, Ireland. Tel.: + 353 1 6373100; fax : +353 1 6373436. E-mail address: [email protected] (F. Mone).
There are predictive factors that can determine prenatally a patient’s probability of successful vaginal delivery. These predictors include age, body mass index (BMI), previous vaginal delivery, and previous VBAC, which may prove positive or negative in deciding outcome [9–11]. Such predictors can be incorporated into prediction models that can be utilized in the prenatal period to facilitate clinicians in counseling women on the basis of the probability of success. The primary aim of the present study was to observe the characteristics of patients who underwent elective repeat cesarean versus TOLAC, and to determine the predictors for success and failure in the TOLAC group. A secondary aim was to determine the rate of neonatal unit admission and maternal morbidity in both groups of women. 2. Materials and methods The present descriptive, retrospective, observational study was conducted in Craigavon Area Hospital, Northern Ireland. The study center is a regional obstetric unit with approximately 4000 deliveries per annum. The study included all patients who gave birth between April 1, 2010, and April 30, 2012, and had at least 1 previous lower segment cesarean delivery. The study was performed with advance approval from the local department of clinical governance. The patients were divided into 2 groups: those who underwent elective repeat cesarean, and those who underwent TOLAC. Patients who
http://dx.doi.org/10.1016/j.ijgo.2013.12.013 0020-7292/© 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
Please cite this article as: Mone F, et al, Predicting why women have elective repeat cesarean deliveries and predictors of successful vaginal birth after cesarean, Int J Gynecol Obstet (2014), http://dx.doi.org/10.1016/j.ijgo.2013.12.013
2
F. Mone et al. / International Journal of Gynecology and Obstetrics xxx (2014) xxx–xxx
had a cesarean delivery for a medical indication that precluded a vaginal delivery, such as placenta accreta, were excluded from the elective repeat cesarean group. At the study institute, all patients who undergo VBAC or elective repeat cesarean have consultant-led care and are counseled about the risks and benefits of each mode of delivery inline with RCOG guidance [5]. Data were obtained from the Northern Ireland Maternity System database. The following patient characteristics were recorded: maternal age, BMI (calculated as weight in kilograms divided by the square of height in meters) at the prenatal visit, maternal ethnicity, previous vaginal delivery, previous successful VBAC, indication for previous cesarean delivery, birth weight in index pregnancy, induction of labor, requirement for neonatal unit admission, and maternal morbidity. Individual predictors for success and failure were determined within the TOLAC group, and maternal morbidity was compared between the 2 groups in terms of maternal complications such as need for blood transfusion, uterine rupture, laparotomy, vaginal trauma and endometritis. Rates of admission to the neonatal unit after delivery between the 2 groups were also observed. Statistical analysis was performed via Excel version 12 (Microsoft, Redmond, WA, USA) and SPSS version 20.0 (IBM, Armonk, NY, USA). Data are reported as mean ± SD for continuous variables and as a percentage for nominal variables. Between the TOLAC and elective repeat cesarean groups, categorical variables were compared via χ2 analysis, and scale variables were compared by either Student t test or Mann– Whitney U test. Statistical significance was assumed at a P value of less than 0.05. 3. Results In total, 893 patients were included in the study: 385 women underwent TOLAC, 493 underwent elective repeat cesarean by maternal request, and 15 women underwent a medically indicated repeat cesarean delivery. Among those who underwent TOLAC, 246 had successful VBAC (63.9%) and 139 (36.1%) delivered by emergency cesarean. The distribution of women among study groups is shown in Fig. 1. The characteristics of patients in the TOLAC and elective repeat cesarean groups are shown in Table 1. In the TOLAC group, 29.6% of women had induction of labor, whereas 69.1% had spontaneous onset of labor. On comparison of the features of the TOLAC and elective repeat cesarean groups, there was a significant difference in the interval from the previous cesarean between the groups. Women who chose elective repeat cesarean had a significantly shorter time interval from the previous cesarean delivery compared with women who chose TOLAC
Table 1 Characteristics of women in the TOLAC and elective repeat cesarean groups.a Characteristic
TOLAC group (n = 385)
Elective repeat cesarean group (n = 508)
P value
Age, y BMI at prenatal visit Cesarean interval, mo Previous vaginal delivery Previous VBAC Previous cesarean for failure to progress
31.0 ± 4.8 26.3 ± 5.49 54.3 ± 40.8 35.6 25.5 27.5
31.0 ± 4.7 27.6 ± 5.8 45.0 ± 31.0 11.8 2.8 39.8
0.259 b0.001 b0.001 b0.001 b0.001 b0.001
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by the square of height in meters); VBAC, vaginal birth after cesarean. a Values are given as mean ± SD or percentage unless stated otherwise.
(P b 0.001). Similarly, women who chose elective repeat cesarean had a significantly higher BMI. Women who had a previous vaginal delivery or VBAC were more likely to select TOLAC (P b 0.001), and those who had a previous cesarean delivery owing to failure to progress were more likely to select elective repeat cesarean. On comparison of the successful and unsuccessful VBAC groups, the rate of maternal morbidity (including need for blood transfusion, endometritis, uterine rupture, and need for laparotomy) was higher in the unsuccessful VBAC (emergency cesarean) group than in the successful VBAC group (10.1% vs 4.1%). Overall, there were 2 uterine ruptures in the unsuccessful VBAC group, giving an overall rupture rate of 0.5% among women who attempted vaginal delivery after cesarean. In the overall TOLAC group (successful + unsuccessful VBAC), the rate of uterine rupture among those exposed to prostaglandin or those who had artificial rupture of membranes was 0%. In the group exposed to oxytocin, the rupture rate was 1.1%. In both cases, uterine rupture led to severe postpartum hemorrhage (N2000 mL), and in 1 case hypoxic ischemic encephalopathy in the neonate. In terms of outcome, there was no difference between the 2 groups in terms of the neonatal admission rate (P = 0.30), although the elective repeat cesarean group had higher rates of maternal morbidity (P b 0.001) when minor vaginal trauma (first- or second-degree tear was omitted) compared with the TOLAC group (Table 2). In terms of outcome for the failed versus the successful VBAC group, rates of admission to the neonatal unit were greater in the unsuccessful VBAC category, with no significant difference in rates of maternal morbidity (Table 3). Among women in the TOLAC group, significant predictors for successful VBAC included having had a previous vaginal delivery or
Patients n=839
Attempted TOLAC
Elective repeat cesarean
n=385
n=508
Successful VBAC
Emergency cesarean
Maternal request
Medically indicated
n=246
n=139
n=493
n=15
Fig. 1. Distribution of deliveries among women undergoing trial of labor after cesarean (TOLAC) and elective repeat cesarean.
Please cite this article as: Mone F, et al, Predicting why women have elective repeat cesarean deliveries and predictors of successful vaginal birth after cesarean, Int J Gynecol Obstet (2014), http://dx.doi.org/10.1016/j.ijgo.2013.12.013
F. Mone et al. / International Journal of Gynecology and Obstetrics xxx (2014) xxx–xxx Table 2 Delivery outcomes among women in the TOLAC and elective repeat cesarean groups.
3
Table 4 Characteristics of women in the TOLAC group by successful and unsuccessful VBAC.a
Outcome
% of TOLAC group (n = 385)
% of elective repeat cesarean group (n = 508)
P value
Characteristic
Successful VBAC (n = 246)
Emergency cesarean (n = 139)
P value
Neonatal unit admission Maternal morbidity
7.8 6.2
10.3 26.2
0.236 b0.001
Age, y BMI Cesarean interval, mo Birth weight, g Augmentation Previous vaginal delivery Previous VBAC Spontaneous onset of labor Previous cesarean for failure to progress Epidural in labor
31.3 ± 4.9 26.0 ± 5.2 60 ± 44.2 3415 ± 528 30.0 47.8 35.1 73.6 35.0 24.1
31.9 ± 4.7 26.89 ± 5.3 44 ± 38.2 3389 ± 655 49.4 14.3 8.6 78.4 23.3 18.6
0.274 0.126 0.001 0.667 b0.001 b0.001 b0.001 0.285 0.100 0.250
successful VBAC, and having a longer interval since the previous cesarean delivery (P b 0.05) (Table 4).
4. Discussion The present findings demonstrate that a considerable proportion of the study women decided to have elective repeat cesarean. The characteristics associated with women who chose TOLAC included a previous vaginal delivery or VBAC, whereas women with a higher BMI and those who had a shorter inter-delivery interval had a tendency to undergo elective repeat cesarean. The latter 2 predictors are risk factors for uterine rupture and VBAC failure [12,13], which may be an indication of appropriate patient selection despite the fact that predictor models were not used in this instance. Although it was not possible to assess the counselling that was provided prenatally in the present study, it might be speculated that patient decision-making, which is greatly influenced by counseling offered by healthcare professionals, is a contributor to patient selection of VBAC or elective repeat cesarean [8]. It would seem from the evidence that previous vaginal delivery or VBAC is the greatest predictor of a successful VBAC, and this should be taken into account when counselling patients because women who have had a successful VBAC show a tendency toward subsequent vaginal delivery with reported rates of 87%–90% [4]. In addition, women who have had a previous vaginal delivery are less likely to have a uterine rupture [6]. Rates of TOLAC are in steady decline, whereas those of cesarean delivery are on the increase. Statistics demonstrate that a previous cesarean or breech delivery comprise the largest proportion of elective repeat cesarean performed in the United Kingdom at a combined rate of 72% [1]. Evidence suggests that this is due to clinician and patient perceptions, as opposed to changes in the characteristics of patients over time [14]. TOLAC has been shown to be more cost-effective than elective repeat cesarean [15], and up to one-third of good candidates for VBAC undergo elective repeat cesarean [8]. As healthcare professionals, it is best practice to provide patients with individualized chances of success scores to enable adequate counselling. These can be provided through validated prediction models, which utilize patient data in the prenatal period and can also determine the risk of adverse outcomes such as uterine rupture [9–11]. Randomized controlled trials are required to determine the proportions of specific adverse outcomes associated with TOLAC and elective repeat cesarean because these data would be important values to quote when counseling patients; currently, most of the available data have come from nonrandomized observational studies [16].
Table 3 Delivery outcomes among women in the TOLAC group by successful and unsuccessful VBAC. Outcome
% of successful VBAC group (n = 246)
% of emergency cesarean group (n = 139)
P value
Neonatal unit admission Maternal morbidity
4.1 6.1
10.1 10.7
b0.001 0.146
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by the square of height in meters); VBAC, vaginal birth after cesarean. a Values are given as mean ± SD or percentage unless stated otherwise.
In summary, the present study showed that the majority of women who had a previous cesarean delivery selected elective repeat cesarean rather than TOLAC. This has long-term implications both clinically and financially. A validated prediction model has the potential to aid the counseling of patients and to aid clinicians in identifying those women who are more likely to have a successful VBAC. Conflict of interest The authors have no conflicts of interest. References [1] Bragg F, Cromwell DA, Edozien LC, Gurol-Urganci I, Mahmood TA, Templeton A, et al. Variation in rates of caesarean section among English NHS trusts after accounting for maternal and clinical risk: cross sectional study. BMJ 2010;341:c5065. [2] Crowther CA, Dodd JM, Hiller JE, Haslam RR, Robinson JS. Birth After Caesarean Study Group. Planned vaginal birth or elective repeat caesarean: patient preference restricted cohort with nested randomised trial. PLoS Med 2012;9(3):e1001192. [3] Levine EM, Ghai V, Barton JJ, Strom CM. Mode of delivery and risk of respiratory diseases in newborns. Obstet Gynecol 2001;97(3):439–42. [4] Edwards MO, Kotecha SJ, Kotecha S. Respiratory distress of the term newborn infant. Paediatr Respir Rev 2013;14(1):29–37. [5] Royal College of Obstetricians and Gynaecologists. Birth after Previous Caesarean Birth. Green-top Guideline No. 45. http://www.rcog.org.uk/files/rcog-corp/GTG4511022011. pdf. Published February 2007. [6] de Lau H, Gremmels H, Schuitemaker NW, Kwee A. Risk of uterine rupture in women undergoing trial of labour with a history of both a caesarean section and a vaginal delivery. Arch Gynecol Obstet 2011;284(5):1053–8. [7] Landon MB, Hauth JC, Leveno KJ, Spong CY, Leindecker S, Varner MW, et al. Maternal and perinatal outcomes associated with a trial of labor after prior cesarean delivery. N Engl J Med 2004;351(25):2581–9. [8] Grobman WA, Lai Y, Landon MB, Spong CY, Leveno KJ, Rouse DJ, et al. Development of a nomogram for prediction of vaginal birth after cesarean delivery. Obstet Gynecol 2007;109(4):806–12. [9] Metz TD, Stoddard GJ, Henry E, Jackson M, Holmgren C, Esplin S. How do good candidates for trial of labor after cesarean (TOLAC) who undergo elective repeat cesarean differ from those who choose TOLAC? Am J Obstet Gynecol 2013;208(6): 458.e1–6. [10] Smith GC, White IR, Pell JP, Dobbie R. Predicting cesarean section and uterine rupture among women attempting vaginal birth after prior cesarean section. PLoS Med 2005;2(9):e252. [11] Troyer LR, Parisi VM. Obstetric parameters affecting success in a trial of labor: designation of a scoring system. Am J Obstet Gynecol 1992;167(4 Pt 1):1099–104. [12] Grobman WA, Lai Y, Landon MB, Spong CY, Leveno KJ, Rouse DJ, et al. Does information available at admission for delivery improve prediction of vaginal birth after cesarean? Am J Perinatol 2009;26(10):693–701. [13] Hibbard JU, Gilbert S, Landon MB, Hauth JC, Leveno KJ, Spong CY, et al. Trial of labor or repeat cesarean delivery in women with morbid obesity and previous cesarean delivery. Obstet Gynecol 2006;108(1):125–33. [14] Grobman WA, Lai Y, Landon M, Spong CY, Rouse DJ, Varner MW, et al. The change in the VBAC rate: An Epidemiologic analysis. Am J Perinatol 2011;25(1):37–43. [15] Gilbert SA, Grobman WA, Landon MB, Varner MW, Wapner RJ, Sorokin Y, et al. Lifetime cost-effectiveness of trial of labor after cesarean in the United States. Value Health 2013;16(6):953–64. [16] Dodd JM, Crowther CA, Huertas E, Guise JM, Horey D. Planned elective repeat caesarean section versus planned vaginal birth for women with a previous caesarean birth. Cochrane Database Syst Rev 2013;12:CD004224.
Please cite this article as: Mone F, et al, Predicting why women have elective repeat cesarean deliveries and predictors of successful vaginal birth after cesarean, Int J Gynecol Obstet (2014), http://dx.doi.org/10.1016/j.ijgo.2013.12.013
Contents lists available at ScienceDirect
International Journal of Gynecology and Obstetrics journal homepage: www.elsevier.com/locate/ijgo
CLINICAL ARTICLE
Predicting why women have elective repeat cesarean deliveries and predictors of successful vaginal birth after cesarean Fionnuala Mone a,⁎, Conor Harrity b, Brenda Toner b, Aine Mcnally b, Beverley Adams c, Aoife Currie c a b c
Department of Obstetrics and Gynaecology, Medicine and Medical Science, University College Dublin, Ireland Department of Obstetrics, Altnagelvin Area Hospital, Londonderry, UK Department of Obstetrics, Craigavon Area Hospital, Craigavon, UK
a r t i c l e
i n f o
Article history: Received 26 August 2013 Received in revised form 16 December 2013 Accepted 13 March 2014 Keywords: Elective repeat cesarean Predictors Trial of labor after cesarean Vaginal birth after cesarean
a b s t r a c t Objective: To compare the characteristics of women who select elective repeat cesarean rather than trial of labor after cesarean (TOLAC) for delivery, and to determine individual predictors for success and failure within a TOLAC group and observe differences in maternal and neonatal morbidity. Methods: The present descriptive, retrospective, observational study was performed in a regional obstetric unit in the United Kingdom. Data were collected from the Northern Ireland Maternity System database on all women who gave birth between April 2010 and April 2012, and had a previous cesarean delivery, and statistical analysis was performed. Results: In total, 893 patients were included in the study: 385 underwent TOLAC and 493 underwent elective repeat cesarean. On comparison, women in the elective repeat cesarean group had a shorter inter-delivery interval and fewer had had a previous vaginal delivery (P b 0.005). Predictors for success in the TOLAC group included previous vaginal delivery and a longer inter-delivery interval (P b 0.05). Successful vaginal birth after cesarean (VBAC) did not have higher rates of maternal morbidity. Conclusion: The majority of patients (56%) chose elective repeat cesarean rather than TOLAC, which has long-term implications both clinically and financially. A validated prediction model might improve patient counseling and identify women with a high likelihood of successful VBAC. © 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
1. Introduction Rising rates of cesarean delivery are an issue of international concern. Rates of cesarean delivery are increasing in the United Kingdom, where the average rate is 25% [1]. Elective repeat cesarean accounts for a significant proportion of the overall rate of cesarean delivery [1, 2]. This has implications not only economically, but also in terms of maternal and neonatal morbidity. Studies have demonstrated that neonates of mothers who undergo elective repeat cesarean can be at greater risk of respiratory morbidity [3,4]. Maternal complications associated with elective repeat cesarean include placenta accreta, visceral injury, intensive care unit admission, hysterectomy, blood transfusion, and a longer duration of hospital stay [5]. Vaginal birth after cesarean (VBAC) is not without its own risks, which include uterine rupture [6], endometritis, and the need for blood transfusion [7]. Awareness of these complications, combined with maternal anxiety about requiring an emergency cesarean, may be the reason that uptake of trial of labor after cesarean (TOLAC) is low [8].
⁎ Corresponding author at: Department of Medicine and Medical Science, University College Dublin, National Maternity Hospital, Holles St, Dublin 2, Ireland. Tel.: + 353 1 6373100; fax : +353 1 6373436. E-mail address: [email protected] (F. Mone).
There are predictive factors that can determine prenatally a patient’s probability of successful vaginal delivery. These predictors include age, body mass index (BMI), previous vaginal delivery, and previous VBAC, which may prove positive or negative in deciding outcome [9–11]. Such predictors can be incorporated into prediction models that can be utilized in the prenatal period to facilitate clinicians in counseling women on the basis of the probability of success. The primary aim of the present study was to observe the characteristics of patients who underwent elective repeat cesarean versus TOLAC, and to determine the predictors for success and failure in the TOLAC group. A secondary aim was to determine the rate of neonatal unit admission and maternal morbidity in both groups of women. 2. Materials and methods The present descriptive, retrospective, observational study was conducted in Craigavon Area Hospital, Northern Ireland. The study center is a regional obstetric unit with approximately 4000 deliveries per annum. The study included all patients who gave birth between April 1, 2010, and April 30, 2012, and had at least 1 previous lower segment cesarean delivery. The study was performed with advance approval from the local department of clinical governance. The patients were divided into 2 groups: those who underwent elective repeat cesarean, and those who underwent TOLAC. Patients who
http://dx.doi.org/10.1016/j.ijgo.2013.12.013 0020-7292/© 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
Please cite this article as: Mone F, et al, Predicting why women have elective repeat cesarean deliveries and predictors of successful vaginal birth after cesarean, Int J Gynecol Obstet (2014), http://dx.doi.org/10.1016/j.ijgo.2013.12.013
2
F. Mone et al. / International Journal of Gynecology and Obstetrics xxx (2014) xxx–xxx
had a cesarean delivery for a medical indication that precluded a vaginal delivery, such as placenta accreta, were excluded from the elective repeat cesarean group. At the study institute, all patients who undergo VBAC or elective repeat cesarean have consultant-led care and are counseled about the risks and benefits of each mode of delivery inline with RCOG guidance [5]. Data were obtained from the Northern Ireland Maternity System database. The following patient characteristics were recorded: maternal age, BMI (calculated as weight in kilograms divided by the square of height in meters) at the prenatal visit, maternal ethnicity, previous vaginal delivery, previous successful VBAC, indication for previous cesarean delivery, birth weight in index pregnancy, induction of labor, requirement for neonatal unit admission, and maternal morbidity. Individual predictors for success and failure were determined within the TOLAC group, and maternal morbidity was compared between the 2 groups in terms of maternal complications such as need for blood transfusion, uterine rupture, laparotomy, vaginal trauma and endometritis. Rates of admission to the neonatal unit after delivery between the 2 groups were also observed. Statistical analysis was performed via Excel version 12 (Microsoft, Redmond, WA, USA) and SPSS version 20.0 (IBM, Armonk, NY, USA). Data are reported as mean ± SD for continuous variables and as a percentage for nominal variables. Between the TOLAC and elective repeat cesarean groups, categorical variables were compared via χ2 analysis, and scale variables were compared by either Student t test or Mann– Whitney U test. Statistical significance was assumed at a P value of less than 0.05. 3. Results In total, 893 patients were included in the study: 385 women underwent TOLAC, 493 underwent elective repeat cesarean by maternal request, and 15 women underwent a medically indicated repeat cesarean delivery. Among those who underwent TOLAC, 246 had successful VBAC (63.9%) and 139 (36.1%) delivered by emergency cesarean. The distribution of women among study groups is shown in Fig. 1. The characteristics of patients in the TOLAC and elective repeat cesarean groups are shown in Table 1. In the TOLAC group, 29.6% of women had induction of labor, whereas 69.1% had spontaneous onset of labor. On comparison of the features of the TOLAC and elective repeat cesarean groups, there was a significant difference in the interval from the previous cesarean between the groups. Women who chose elective repeat cesarean had a significantly shorter time interval from the previous cesarean delivery compared with women who chose TOLAC
Table 1 Characteristics of women in the TOLAC and elective repeat cesarean groups.a Characteristic
TOLAC group (n = 385)
Elective repeat cesarean group (n = 508)
P value
Age, y BMI at prenatal visit Cesarean interval, mo Previous vaginal delivery Previous VBAC Previous cesarean for failure to progress
31.0 ± 4.8 26.3 ± 5.49 54.3 ± 40.8 35.6 25.5 27.5
31.0 ± 4.7 27.6 ± 5.8 45.0 ± 31.0 11.8 2.8 39.8
0.259 b0.001 b0.001 b0.001 b0.001 b0.001
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by the square of height in meters); VBAC, vaginal birth after cesarean. a Values are given as mean ± SD or percentage unless stated otherwise.
(P b 0.001). Similarly, women who chose elective repeat cesarean had a significantly higher BMI. Women who had a previous vaginal delivery or VBAC were more likely to select TOLAC (P b 0.001), and those who had a previous cesarean delivery owing to failure to progress were more likely to select elective repeat cesarean. On comparison of the successful and unsuccessful VBAC groups, the rate of maternal morbidity (including need for blood transfusion, endometritis, uterine rupture, and need for laparotomy) was higher in the unsuccessful VBAC (emergency cesarean) group than in the successful VBAC group (10.1% vs 4.1%). Overall, there were 2 uterine ruptures in the unsuccessful VBAC group, giving an overall rupture rate of 0.5% among women who attempted vaginal delivery after cesarean. In the overall TOLAC group (successful + unsuccessful VBAC), the rate of uterine rupture among those exposed to prostaglandin or those who had artificial rupture of membranes was 0%. In the group exposed to oxytocin, the rupture rate was 1.1%. In both cases, uterine rupture led to severe postpartum hemorrhage (N2000 mL), and in 1 case hypoxic ischemic encephalopathy in the neonate. In terms of outcome, there was no difference between the 2 groups in terms of the neonatal admission rate (P = 0.30), although the elective repeat cesarean group had higher rates of maternal morbidity (P b 0.001) when minor vaginal trauma (first- or second-degree tear was omitted) compared with the TOLAC group (Table 2). In terms of outcome for the failed versus the successful VBAC group, rates of admission to the neonatal unit were greater in the unsuccessful VBAC category, with no significant difference in rates of maternal morbidity (Table 3). Among women in the TOLAC group, significant predictors for successful VBAC included having had a previous vaginal delivery or
Patients n=839
Attempted TOLAC
Elective repeat cesarean
n=385
n=508
Successful VBAC
Emergency cesarean
Maternal request
Medically indicated
n=246
n=139
n=493
n=15
Fig. 1. Distribution of deliveries among women undergoing trial of labor after cesarean (TOLAC) and elective repeat cesarean.
Please cite this article as: Mone F, et al, Predicting why women have elective repeat cesarean deliveries and predictors of successful vaginal birth after cesarean, Int J Gynecol Obstet (2014), http://dx.doi.org/10.1016/j.ijgo.2013.12.013
F. Mone et al. / International Journal of Gynecology and Obstetrics xxx (2014) xxx–xxx Table 2 Delivery outcomes among women in the TOLAC and elective repeat cesarean groups.
3
Table 4 Characteristics of women in the TOLAC group by successful and unsuccessful VBAC.a
Outcome
% of TOLAC group (n = 385)
% of elective repeat cesarean group (n = 508)
P value
Characteristic
Successful VBAC (n = 246)
Emergency cesarean (n = 139)
P value
Neonatal unit admission Maternal morbidity
7.8 6.2
10.3 26.2
0.236 b0.001
Age, y BMI Cesarean interval, mo Birth weight, g Augmentation Previous vaginal delivery Previous VBAC Spontaneous onset of labor Previous cesarean for failure to progress Epidural in labor
31.3 ± 4.9 26.0 ± 5.2 60 ± 44.2 3415 ± 528 30.0 47.8 35.1 73.6 35.0 24.1
31.9 ± 4.7 26.89 ± 5.3 44 ± 38.2 3389 ± 655 49.4 14.3 8.6 78.4 23.3 18.6
0.274 0.126 0.001 0.667 b0.001 b0.001 b0.001 0.285 0.100 0.250
successful VBAC, and having a longer interval since the previous cesarean delivery (P b 0.05) (Table 4).
4. Discussion The present findings demonstrate that a considerable proportion of the study women decided to have elective repeat cesarean. The characteristics associated with women who chose TOLAC included a previous vaginal delivery or VBAC, whereas women with a higher BMI and those who had a shorter inter-delivery interval had a tendency to undergo elective repeat cesarean. The latter 2 predictors are risk factors for uterine rupture and VBAC failure [12,13], which may be an indication of appropriate patient selection despite the fact that predictor models were not used in this instance. Although it was not possible to assess the counselling that was provided prenatally in the present study, it might be speculated that patient decision-making, which is greatly influenced by counseling offered by healthcare professionals, is a contributor to patient selection of VBAC or elective repeat cesarean [8]. It would seem from the evidence that previous vaginal delivery or VBAC is the greatest predictor of a successful VBAC, and this should be taken into account when counselling patients because women who have had a successful VBAC show a tendency toward subsequent vaginal delivery with reported rates of 87%–90% [4]. In addition, women who have had a previous vaginal delivery are less likely to have a uterine rupture [6]. Rates of TOLAC are in steady decline, whereas those of cesarean delivery are on the increase. Statistics demonstrate that a previous cesarean or breech delivery comprise the largest proportion of elective repeat cesarean performed in the United Kingdom at a combined rate of 72% [1]. Evidence suggests that this is due to clinician and patient perceptions, as opposed to changes in the characteristics of patients over time [14]. TOLAC has been shown to be more cost-effective than elective repeat cesarean [15], and up to one-third of good candidates for VBAC undergo elective repeat cesarean [8]. As healthcare professionals, it is best practice to provide patients with individualized chances of success scores to enable adequate counselling. These can be provided through validated prediction models, which utilize patient data in the prenatal period and can also determine the risk of adverse outcomes such as uterine rupture [9–11]. Randomized controlled trials are required to determine the proportions of specific adverse outcomes associated with TOLAC and elective repeat cesarean because these data would be important values to quote when counseling patients; currently, most of the available data have come from nonrandomized observational studies [16].
Table 3 Delivery outcomes among women in the TOLAC group by successful and unsuccessful VBAC. Outcome
% of successful VBAC group (n = 246)
% of emergency cesarean group (n = 139)
P value
Neonatal unit admission Maternal morbidity
4.1 6.1
10.1 10.7
b0.001 0.146
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by the square of height in meters); VBAC, vaginal birth after cesarean. a Values are given as mean ± SD or percentage unless stated otherwise.
In summary, the present study showed that the majority of women who had a previous cesarean delivery selected elective repeat cesarean rather than TOLAC. This has long-term implications both clinically and financially. A validated prediction model has the potential to aid the counseling of patients and to aid clinicians in identifying those women who are more likely to have a successful VBAC. Conflict of interest The authors have no conflicts of interest. References [1] Bragg F, Cromwell DA, Edozien LC, Gurol-Urganci I, Mahmood TA, Templeton A, et al. Variation in rates of caesarean section among English NHS trusts after accounting for maternal and clinical risk: cross sectional study. BMJ 2010;341:c5065. [2] Crowther CA, Dodd JM, Hiller JE, Haslam RR, Robinson JS. Birth After Caesarean Study Group. Planned vaginal birth or elective repeat caesarean: patient preference restricted cohort with nested randomised trial. PLoS Med 2012;9(3):e1001192. [3] Levine EM, Ghai V, Barton JJ, Strom CM. Mode of delivery and risk of respiratory diseases in newborns. Obstet Gynecol 2001;97(3):439–42. [4] Edwards MO, Kotecha SJ, Kotecha S. Respiratory distress of the term newborn infant. Paediatr Respir Rev 2013;14(1):29–37. [5] Royal College of Obstetricians and Gynaecologists. Birth after Previous Caesarean Birth. Green-top Guideline No. 45. http://www.rcog.org.uk/files/rcog-corp/GTG4511022011. pdf. Published February 2007. [6] de Lau H, Gremmels H, Schuitemaker NW, Kwee A. Risk of uterine rupture in women undergoing trial of labour with a history of both a caesarean section and a vaginal delivery. Arch Gynecol Obstet 2011;284(5):1053–8. [7] Landon MB, Hauth JC, Leveno KJ, Spong CY, Leindecker S, Varner MW, et al. Maternal and perinatal outcomes associated with a trial of labor after prior cesarean delivery. N Engl J Med 2004;351(25):2581–9. [8] Grobman WA, Lai Y, Landon MB, Spong CY, Leveno KJ, Rouse DJ, et al. Development of a nomogram for prediction of vaginal birth after cesarean delivery. Obstet Gynecol 2007;109(4):806–12. [9] Metz TD, Stoddard GJ, Henry E, Jackson M, Holmgren C, Esplin S. How do good candidates for trial of labor after cesarean (TOLAC) who undergo elective repeat cesarean differ from those who choose TOLAC? Am J Obstet Gynecol 2013;208(6): 458.e1–6. [10] Smith GC, White IR, Pell JP, Dobbie R. Predicting cesarean section and uterine rupture among women attempting vaginal birth after prior cesarean section. PLoS Med 2005;2(9):e252. [11] Troyer LR, Parisi VM. Obstetric parameters affecting success in a trial of labor: designation of a scoring system. Am J Obstet Gynecol 1992;167(4 Pt 1):1099–104. [12] Grobman WA, Lai Y, Landon MB, Spong CY, Leveno KJ, Rouse DJ, et al. Does information available at admission for delivery improve prediction of vaginal birth after cesarean? Am J Perinatol 2009;26(10):693–701. [13] Hibbard JU, Gilbert S, Landon MB, Hauth JC, Leveno KJ, Spong CY, et al. Trial of labor or repeat cesarean delivery in women with morbid obesity and previous cesarean delivery. Obstet Gynecol 2006;108(1):125–33. [14] Grobman WA, Lai Y, Landon M, Spong CY, Rouse DJ, Varner MW, et al. The change in the VBAC rate: An Epidemiologic analysis. Am J Perinatol 2011;25(1):37–43. [15] Gilbert SA, Grobman WA, Landon MB, Varner MW, Wapner RJ, Sorokin Y, et al. Lifetime cost-effectiveness of trial of labor after cesarean in the United States. Value Health 2013;16(6):953–64. [16] Dodd JM, Crowther CA, Huertas E, Guise JM, Horey D. Planned elective repeat caesarean section versus planned vaginal birth for women with a previous caesarean birth. Cochrane Database Syst Rev 2013;12:CD004224.
Please cite this article as: Mone F, et al, Predicting why women have elective repeat cesarean deliveries and predictors of successful vaginal birth after cesarean, Int J Gynecol Obstet (2014), http://dx.doi.org/10.1016/j.ijgo.2013.12.013
