Committee opinion. Induction of labor for vaginal birth after cesarean delivery

A recent population-based study of vaginal birth after cesarean delivery (VBAC) attempts observed uterine rupture rates of 24.5 per 1,000 with prostaglandin-induced labor, while the uterine rupture rates with spontaneous labor and labor induced without prostaglandins were lower (5.2/1,000 and 7.71/1,000 respectively). The authors did not confirm the diagnoses by examining individual medical records, so the actual incidence of uterine rupture may have been overstated. Despite this limitation, the Committee on Obstetric Practice concludes that the risk of uterine rupture during VBAC attempts is substantially increased with the use of various prostaglandin cervical ripening agents for the induction of labor, and their use for this purpose is discouraged.     

ACOG Committee Opinion No. 342: induction of labor for vaginal birth after cesarean delivery

Induction of labor in women who have had cesarean deliveries may be necessary because of fetal or maternal indications. The potentially increased risk of uterine rupture should be discussed with the patient and documented in the medical record. Selecting women most likely to give birth vaginally and avoiding the sequential use of prostaglandins and oxytocin appear to offer the lowest risks. Misoprostol should not be used in patients who have had cesarean deliveries or major uterine surgery.     

ACOG committee opinion. No. 339: Analgesia and cesarean delivery rates

Neuraxial analgesia techniques are the most effective and least depressant treatments for labor pain. The American College of Obstetricians and Gynecologists previously recommended that practitioners delay initiating epidural analgesia in nulliparous women until the cervical dilatation reached 4-5 cm. However, more recent studies have shown that epidural analgesia does not increase the risks of cesarean delivery. The choice of analgesic technique, agent, and dosage is based on many factors, including patient preference, medical status, and contraindications. The fear of unnecessary cesarean delivery should not influence the method of pain relief that women can choose during labor.     

The duration of labor in primiparas undergoing vaginal birth after cesarean delivery

The purpose of this retrospective investigation was to evaluate the duration of labor in women having a trial of labor after a previous low transverse cervical cesarean delivery for dystocia. We specifically sought to determine whether these patients experienced a labor similar to that of the nulliparous or multiparous woman. During the study period, 73 women who had previously undergone a cesarean for dystocia had a successful trial of labor. We matched each study patient to two controls. One control was nulliparous and the second was a woman who had undergone a previous uncomplicated vaginal delivery. Thirty-six study patients had had a cesarean in the latent phase of labor (group I), 29 in the active phase of labor (group II), and eight in the second stage of labor (group III). With the exception of group I patients, the first and second stages of labor were similar to those of nulliparous control patients. Patients in group I had a significantly longer first stage of labor than did the nulliparous controls. There was no significant difference in oxytocin requirements among the three groups. We conclude that primiparous women who have had a previous cesarean delivery for dystocia have a duration of labor similar in length or longer than that of nulliparous women.     

Induction of labor after one prior cesarean: predictors of vaginal delivery

OBJECTIVE: To estimate the characteristics most associated with vaginal birth in patients undergoing induction of labor after 1 prior cesarean delivery. METHODS: All patients who presented for induction of labor from 1996 to 2001 with a history of 1 prior cesarean delivery were identified. Relevant demographic and obstetric data were abstracted from the charts. Univariate analysis was used to identify predictive factors associated with vaginal birth after cesarean. Binary logistic regression was further used to identify which factors were independently associated with the outcome measure. RESULTS: Of the 429 women included in the study, 334 (77.9%) had a successful trial of labor. In the final binary logistic regression equation, prior vaginal delivery (odds ratio [OR] 3.75; 95% confidence interval [CI] 1.96, 7.18) remained independently associated with an increased chance of a vaginal delivery after a trial of labor. Conversely, prior cesarean delivery for dystocia (OR 0.46; 95% CI 0.27, 0.79), induction on or past the estimated date of delivery (OR 0.46; 95% CI 0.27, 0.78), need for cervical ripening (OR 0.35; 95% CI 0.20, 0.61), and maternal gestational or preexisting diabetes (OR 0.16; 95% CI 0.06, 0.40) were all factors associated with a decreased likelihood of achieving a successful trial of labor. CONCLUSION: Several factors are available which may assist in identifying patients with the best chance of vaginal delivery after an induction of labor in the presence of a prior low-transverse cesarean scar. LEVEL OF EVIDENCE: II-2     

Safety of vaginal birth after cesarean delivery.

OBJECTIVE: To compare the outcomes of labor induction in women with a history of 1 cesarean section (CS) who undergo trial of labor. METHODS: A prospective observational study of 702 pregnant women who had 1 previous CS was conducted at Women's Hospital, Hamad Medical Corporation, Doha, Qatar, between April 2003 and April 2004. Those with no history of vaginal delivery were assigned to one group and those with a history of vaginal delivery were assigned to another group, and the latter group was then divided into 2 subgroups according to the results of trial of labor. RESULTS: Of these 702 women with a history of 1 CS, 62.4% also had a history of vaginal delivery. After trial of labor, vaginal delivery occurred more often among women with no history of vaginal delivery (64.8%). Moreover, trial of labor resulted in a vaginal delivery more often in women who were delivered only once and by CS (87.7%) than in women who also had a history of vaginal delivery (79.2%). CONCLUSION: These findings indicate that women who have had a CS should strongly consider natural delivery for subsequent pregnancies.     

Current concepts regarding vaginal birth after cesarean delivery

PURPOSE OF REVIEW: To review the current literature on vaginal birth after cesarean delivery efficacy and safety. RECENT FINDINGS: There are two major themes in current vaginal birth after cesarean delivery research. The first is continued work on the short-term safety, including maternal events such as uterine rupture and perinatal death. The second theme focuses on identifying predictors for success and failure. SUMMARY: Current information suggests that the rate of major maternal and neonatal complications with vaginal birth after cesarean delivery is low, and this option should be offered to women with a single prior low transverse cesarean. Future research should focus on an evaluation of both short-term and long-term consequences of vaginal birth after cesarean delivery compared with elective repeat cesarean section.     

Effect of prior vaginal delivery or prior vaginal birth after cesarean delivery on obstetric outcomes in women undergoing trial of labor

OBJECTIVE: We sought to study the effects of prior vaginal delivery or prior vaginal birth after cesarean delivery (VBAC) on the success of a trial of labor after a cesarean delivery. METHODS: An observational study of patients who underwent a trial of labor after a single low-transverse cesarean delivery. Patients with a previous cesarean delivery and no vaginal birth were compared with patients with a single vaginal delivery before or after the previous cesarean delivery. The rates of successful VBAC, uterine rupture, and scar dehiscence were analyzed. Multivariable regression was performed to adjust for confounding variables. RESULTS: Of 2,204 patients, 1,685 (76.4%) had a previous cesarean delivery and no vaginal delivery, 198 (9.0%) had a vaginal delivery before the cesarean delivery, and 321 (14.6%) had a prior VBAC. The rate of successful trial of labor was 70.1%, 81.8%, and 93.1%, respectively (P <.001). A prior VBAC was associated with fewer third- and fourth-degree lacerations (8.5% versus 2.5% versus 3.7%, P <.001) and fewer operative vaginal deliveries (14.7% versus 5.6% versus 1.9%, P <.001) but not with uterine rupture (1.5% versus 0.5% versus 0.3%, P =.12). Patients with a prior VBAC had, in addition, a higher rate of uterine scar dehiscence (21.8%) compared with patients with a previous cesarean delivery and no vaginal delivery (5.3%; P =.001). CONCLUSION: A prior vaginal delivery and, particularly, a prior VBAC are associated with a higher rate of successful trial of labor compared with patients with no prior vaginal delivery. In addition, prior VBAC is associated with an increased rate of uterine scar dehiscence.     

Increased success of trial of labor after previous vaginal birth after cesarean

OBJECTIVE: To estimate whether a history of a previous successful vaginal birth after cesarean delivery (VBAC) has an effect on a subsequent VBAC attempt. METHODS: A chart review of cases identified from the International Classification of Diseases, 9th Revision (ICD-9) codes and cases identified in the logbooks on Labor and Delivery yielded 1,216 cases of attempted VBAC from 1996 to 2000. Data gathered from these cases included history of previous successful VBAC. Variables of interest included previous successful normal spontaneous vaginal delivery, history of diabetes, labor induction, and recurrent indication for cesarean delivery. RESULTS: Of the 336 patients with a history of one or more previous successful VBAC attempts, 94.6% had a subsequent successful VBAC, whereas 70.5% of the remaining 880 patients were successful (P <.001). For those patients with one or more previous successful normal spontaneous vaginal deliveries, 87.8% had a successful VBAC, whereas 75.6% were successful without this history (P =.001). The presence of diabetes and a recurrent indication for cesarean delivery both decreased VBAC success and were independently associated with poor outcome (P <.001). Patients with a history of previous VBAC were 7 times more likely to have a subsequent VBAC success (odds ratio 7.40, 95% confidence interval 4.51-12.16; P <.001). Those with a history of previous normal spontaneous vaginal delivery were not more likely to have a successful VBAC when the other variables were controlled. Induction did not affect VBAC outcome. CONCLUSION: A history of a previous successful VBAC increases the likelihood for success with future attempts. Maternal diabetes and history of a recurrent indication for cesarean delivery are poor prognosticators for successful trial of labor. LEVEL OF EVIDENCE: II-2     

Prediction of vaginal birth after one ceasarean delivery for non-progressive labor

Purpose

A model exists that predicts the probability of vaginal birth after cesarean (VBAC). That model is not stratified by indication at first cesarean. The aim of the study was to identify factors that may predict successful VBAC in patients operated for arrest of dilatation or descent at their first cesarean.

Methods

Retrospective analysis of all women with trials of labor after one cesarean (TOLAC) for non-progressive labor between November 2008 and October 2015 was performed (n = 231). A multivariate logistic regression analysis was carried out to generate a prediction model for VBAC at hospital admission for planned TOLAC.

Results

During the study period, we had 231 parturient women who chose to undergo TOLAC following one previous cesarean delivery for non-progressive labor. Successful VBAC occurred in 155 (67.0%) parturient women. A model consisting of previous successful VBAC, lower head station on decision at previous cesarean delivery, lower newborn weight at previous cesarean delivery and larger cervical effacement on admission at delivery planned for TOLAC correctly classified 75.3% of cases (R ² = 0.324, AUC 0.80, 95% CI 0.70–0.89, p < 0.001).

Conclusion

A predictive model, which incorporates four variables available at hospital admission for the planned TOLAC, has been developed that allows the determination of likelihood of successful VBAC following one cesarean delivery for non-progressive labor.

     

Predicting failure of a vaginal birth attempt after cesarean delivery

OBJECTIVE: To identify a group of clinical factors that could be used to accurately predict failure in women attempting vaginal birth after cesarean (VBAC). METHODS: We conducted a planned secondary analysis of a retrospective cohort study of women who were offered VBAC from 1996 to 2000 in 17 community and university hospitals. We collected information about maternal history and outcomes of the index pregnancy. We used univariable and multivariable statistical methods to develop a multivariable prediction model for the outcome of VBAC failure. RESULTS: A total of 13,706 patients attempted VBAC, with a failure rate of 24.5%. Six variables were significantly associated with VBAC failure in our final logistic regression model: gestational age at delivery, maternal age, maternal race, labor type (spontaneous, augmented, or induced), history of vaginal delivery, and cephalopelvic disproportion or failed induction (combined variable) as prior cesarean indication. The area under the receiver operating characteristics curve is 0.717. To achieve a sensitivity of approximately 75%, a false-positive rate of approximately 40% would result. CONCLUSION: Our results indicate that significant clinical variables (prelabor and labor) cannot reliably predict VBAC failure. LEVEL OF EVIDENCE: II.     

Using active management of labor and vaginal birth after previous cesarean delivery to lower cesarean delivery rates: A 10-year experience

Objective: Our objective was to analyze the statistics on cesarean delivery rates and the factors that have led to a reduction in these rates. Study Design: A retrospective analysis was done of delivery statistics from a 10-year period, January 1, 1989, to December 31, 1998. We investigated the changes made in the methods of delivery during the study period. The data were divided into 1-year periods and analyzed by χ² tables. Results: The overall cesarean delivery rate decreased from 16.59% to 10.92%; the primary cesarean delivery rate decreased from 9.22% to 7.11% and the repeated cesarean delivery rate from 7.37% to 3.81%. All these decreases were statistically significant. An increase in the rate of active management of labor by increasing oxytocin use and encouraging a trial of labor after previous cesarean delivery was also statistically significant. No changes in the outcome were observed in terms of neonatal morbidity and mortality rates. Conclusion: We found that our working plan for management of labor and delivery yielded and maintained a successful decline in the cesarean delivery rates without any negative effect on neonatal or maternal mortality rates. This low rate was maintained for a 10-year period. (Am J Obstet Gynecol 2001;184:1535-43.)     

Development of a nomogram for prediction of vaginal birth after cesarean delivery

OBJECTIVE: To develop a model based on factors available at the first prenatal visit that predicts chance of successful vaginal birth after cesarean delivery (VBAC) for individual patients who undergo a trial of labor. METHODS: All women with one prior low transverse cesarean who underwent a trial of labor at term with a vertex singleton gestation were identified from a concurrently collected database of deliveries at 19 academic centers during a 4-year period. Using factors identifiable at the first prenatal visit, we analyzed different classification techniques in an effort to develop a meaningful prediction model for VBAC success. After development and cross-validation, this model was represented by a graphic nomogram. RESULTS: Seven-thousand six hundred sixty women were available for analysis. The prediction model is based on a multivariable logistic regression, including the variables of maternal age, body mass index, ethnicity, prior vaginal delivery, the occurrence of a VBAC, and a potentially recurrent indication for the cesarean delivery. After analyzing the model with cross-validation techniques, it was found to be both accurate and discriminating. CONCLUSION: A predictive nomogram, which incorporates six variables easily ascertainable at the first prenatal visit, has been developed that allows the determination of a patient-specific chance for successful VBAC for those women who undertake trial of labor. LEVEL OF EVIDENCE: II.