Vaginal birth after cesarean delivery: a group practice’s approach to minimizing failed trial of labor

Objective: Among women attempting a trial of labor (TOL) after a prior abdominal delivery, 60–80% accomplish a vaginal birth after cesarean (VBAC). McMahon and coworkers (N Engl J Med, 1996) have indicated that at a 60% success level for TOL, the remaining 40% incurred enough major complications that the scheduled repeat cesarean section group was less morbid overall. The same authors speculated that a success rate of 80% might be necessary for the TOL group’s morbidity to be superior. We sought to review our group’s patient selection experience during an interval when successful TOL consistently exceeded 80%.Methods: The study interval ranged from January 1995 through June 1997 and was limited to patients with one previous low transverse cesarean section. Rather than using administrative or charge-related diagnoses, we analyzed a departmental database that included each delivering physician’s selection of one of four VBAC categories: successful VBAC, unsuccessful VBAC, patient declined trial of labor, or physician advised against trial of labor. All deliveries were at a single institution and were performed by one of seven obstetricians in a group practice.Results: During the study interval, 332 women provided a history of a single previous cesarean delivery. Of these 332, a total of 173 attempted a TOL and 150 of the 173 (87%) were successful. Fifty-eight of the 332 (18%) declined a trial of labor despite being assessed as excellent candidates, and 101 (30%) were advised against a TOL by their physician. Most common reasons for physicians discouraging labor included malpresentation, fetal macrosomia, and clinically small pelvis. Complications for the 23 of 173 (13%) experiencing a failed TOL included 1 asymptomatic partial separation of a uterine scar and 4 cases of puerperal fever; neither transfusion nor hysterectomy was required.Conclusions: This study demonstrates that in a population of women with one prior cesarean delivery, it is possible for a group practice to achieve a TOL success rate exceeding 80%. In our opinion the managing physician selecting out those patients least likely to attain a successful TOL contributes to a low failed TOL rate. We speculate that an analysis for best practice patterns within our group might reveal information of value for future practice guidelines.     

Vaginal birth after cesarean section: trial of labor or repeat cesarean section? A decision analysis

OBJECTIVE: The risk of perinatal death associated with labor after previous cesarean section appears higher than with a repeated cesarean section. On the other hand, repeated cesarean sections are associated with increased maternal morbidity and mortality from placental pathologic conditions (previa or accreta) on subsequent pregnancies. The study was undertaken to analyze the decision for a trial of labor or a repeated cesarean section, after a prior cesarean section, with varying desire for an additional pregnancy. STUDY DESIGN: A model was formulated using a decision tree, based on the reported risks of the two approaches. Sensitivity analysis was performed over a variety of probabilities (eg, chance of uterine rupture or neonatal death, chance of rescue cesarean section, desire for an additional pregnancy) and utilities (eg, use of hysterectomy or neonatal death). RESULTS: The model favors a trial of labor if it has a chance of success of 50% or above and if the wish for additional pregnancies after a cesarean section is estimated at near 10% to 20% or above because the delayed risks from a repeated cesarean section are greater than its immediate benefit. The model was robust over a wide range of assumptions. CONCLUSION: An optimal decision for a trial of labor or a repeated cesarean section is substantially determined by the wish for future pregnancies. The default option of a repeated cesarean section is not directly applicable in populations in which family planning often extends over two children.     

Can a vaginal birth after cesarean delivery be a normal labor and birth? Lessons from midwifery applied to trial of labor after a previous cesarean delivery

Women who undergo a trial of labor after a previous cesarean delivery (TOLAC) have special needs prenatally and during the intrapartum period. Counseling about the choice of TOLAC versus an elective repeat cesarean delivery involves complex statistical concepts. Prenatal counseling that is patient centered, individualized, and presented in a way that addresses the health literacy and health numeracy of the recipient encompasses best practices that support patient decision making. Evidence-based practices during labor that support vaginal birth and increase patient satisfaction are of special value for this population.     

Vaginal birth after cesarean: what's new in the new millennium?

PURPOSE OF REVIEW: This brief review will focus exclusively on very recent developments and controversial aspects of vaginal birth after cesarean. Only papers published in 2001 or 2002 are included. RECENT FINDINGS: Recent studies have addressed the intrapartum management of vaginal birth after cesarean patients and the safety of trial of labor compared with elective repeat cesarean. SUMMARY: The recent trend has been towards a more cautious approach to vaginal birth after cesarean. Some are concerned that this trend may limit childbirth options for those women who wish to avoid repeat cesarean operations.     

Prediction of successful trial of labor after cesarean – the benefit of prior vaginal delivery

Objective: To determine predictive factors for vaginal birth after cesarean section (VBAC).

Methods: A retrospective cohort study of all women with singleton pregnancies and a prior single low transverse cesarean section (CS) who attempted vaginal delivery in a tertiary hospital (2010–2014). Pregnancy outcome of women with VBAC was compared to those who failed vaginal delivery. Sub-analysis for women with no prior vaginal deliveries was performed. Pregnancies with non-cephalic presentation, estimated fetal weight?>4000 g and any contraindications for vaginal delivery were excluded.

Results: Of the 40 714 deliveries, 1767 women met inclusion criteria. Among them 1563 (88.5%) had a VBAC and 204 (11.5%) failed. There was no significant difference between the groups regarding maternal age, comorbidities and pregnancy complications. Predictors for VBAC were (odds ratio, 95% confidence interval) interval from prior CS (1.13, 1.04–1.22, p=0.004), previous VBAC (2.77, 1.60–4.78, p?<?0.001), prior vaginal delivery prior to the CS (3.05, 1.73–5.39, p?<?0.001) and induction of labor (0.62, 0.40–0.97, p?=?0.03). For women with no prior vaginal birth, only birthweight was associated with VBAC (0.99, 0.99–1.00, p?=?0.02).

Conclusion: While different variables may influence the rate of VBAC, the predictive ability of VBAC for women with no previous vaginal deliveries remains poor.     

Vaginal breech delivery: is it still an option?

OBJECTIVE: To provide local data on term breech delivery for future guidance. STUDY DESIGN: Retrospective, 'intended-mode-of-delivery' analysis of 711 antenatally uncomplicated singleton breech deliveries at >or=37 weeks: 445 (63%) planned for vaginal delivery (VD) (no fetal growth restriction, fetal weight 2000-4000 g, adequate pelvic size, maternal consent) and 266 for cesarean section (CS). OUTCOME MEASURES: Apgar score, cord blood acid-base status, childhood deaths and disability. RESULTS: Perinatal mortality was nil in both groups. Low 1-min Apgar scores and low arterial cord blood pH were significantly more frequent in planned VD, but not low Apgar scores at 5 or 10 min or low venous pH. Metabolic acidosis, neonatal intensive care, neonatal seizures, birth trauma, childhood death (CS=1), and neurodevelopmental handicaps (CS=2, VD=1) were equally common. CONCLUSION: Our results do not disqualify selective vaginal breech delivery at term and beyond as an option.     

Breech presenting twin A: is vaginal delivery safe?

The aim of our study was to compare the neonatal outcome of vaginally delivered breech-presenting twins (VD) to those delivered by cesarean (CS). Maternal and neonatal charts of all live, non-anomalous twins delivered at > or =25 weeks of gestation, in a single tertiary care center, over an 11-year period were reviewed. Of 517 twins delivered, 130 breech-presenting twins were analyzed. Thirty-five (26.9%) were delivered vaginally and 95 (73.1%) by cesarean. More patients presented in labor with advanced cervical dilation in the VD compared to the CS group. There was no difference in the incidence of respiratory distress syndrome, intraventricular hemorrhage, need for mechanical ventilation, length of nursery stay or neonatal mortality rate when twin A was compared in the two groups. However, one breech-presenting twin in the VD group had a traumatic delivery at 32 weeks of gestation that caused a spine fracture followed by immediate neonatal death. Although there seems to be no compromise in the immediate neonatal outcome of breech-presenting twins delivered vaginally compared to those delivered by cesarean, the case of head entrapment that led to intrapartum death is quite alarming. Based on our study, we cannot advocate normal vaginal delivery when twin A is non-vertex: cesarean seems to be a safer route of delivery.     

Operative vaginal delivery: a cause of birth injury or is it?

Operative vaginal delivery has been maligned since the days of W.J. Little with the word "forceps" becoming nearly synonymous with "Birth Injury" and "Cerebral Palsy." However in his presentation to the Obstetrical Society of London in 1861, Little's emphasis was on difficult labors being the culprit in subsequent disabilities in the offspring. Instrumented deliveries in that era were the end result of a long, obstructed labor performed for maternal benefit and to avoid a destructive procedure to the fetus thus allowing a chance at life. If there had been a normal progress in labor, operative assistance for delivery would not have been needed. Thus, was it the instrument or the obstructed labor that led to fetal injury? In this article, we will review what injuries to the fetus and the mother can be directly attributable to the instrument. We will explore the processes of labor, conduct of labor management, and concurrent fetal factors that can modulate the occurrence of birth trauma. Evidence regarding inexperience and improper use as contributing to injury will also be explored.     

Eating and drinking in labor: Should it be allowed?

Eating and drinking in labor is a controversial subject with practice varying widely by practitioners, within facilities, and around the world. The risk of aspiration pneumonitis and anesthesia-related deaths at cesarean section has resulted in adherence to historical practices of starving women in labor. Studies have shown that the risk of this anesthetic-related complication is low. It is the fear of the birth-attendant to bear full responsibility if a patient inhales gastric contents when giving in to demands for liberal fluid and food regimes during labor that governs practice. While the bulk of evidence supports fluid intake in labor, there are insufficient published studies to draw conclusions about the relationship between fasting times and the risk of pulmonary aspiration during labor. Whether or not allowing food and fluid throughout labor is beneficial or harmful can only be determined by further research. A computerized search was done of MEDLINE, PUBMED, SCOPUS and CINAHL, as well of historical articles, texts, articles from indexed journals, and references cited in published works.     

Neonatal hypoxia of the second twin after vaginal delivery of the first twin: what matters?*

Objective: Optimal management of twin deliveries is controversial. We aimed to assess potential risk factors correlated to the development of hypoxia in the second twin after vaginal delivery of the first twin.

Study design: This is a retrospective observational study including diamniotic twin pregnancies delivering at our Institution at 35 weeks of gestational age or more, weighing ≥1800?g. Hypoxia was defined as at least one of the following: Apgar score <5 at 10 minute, neonatal resuscitation for >10 minutes, neonatal acidosis (pH ≤7 and/or BE ≥12?mmol/L).

Results: A number of 275 diamniotic twin pregnancies met the inclusion criteria and were divided within the following groups: (1) second twin not developing neonatal hypoxia (n?=?265); and (2) second twin developing neonatal hypoxia (n?=?10). The rate of second twins with neonatal hypoxia during the study period was 3.6% (10/275). Abnormal cardiotocography during the intertwin delivery interval, defined as ACOG category III, was significantly correlated to second twin hypoxia. Of interest, there was no significant difference in the intertwin delivery interval between the study groups. In addition, breech presentation of the second twin did not show to be a risk factor for neonatal hypoxia. None of the second twins developing neonatal hypoxia was reported to have encephalopathy (follow up of at least 24 months). At multivariate analysis, only abnormal cardiotocography was an independent risk factor for second twin hypoxia (OR 17.8, 95% CI 4.1–77.2).

Conclusions: In our study, neonatal hypoxia was significantly correlated to abnormal cardiotocography, while intertwin delivery interval was not correlated to the development of this adverse neonatal outcome.     

Should we allow a trial of labor after a previous cesarean for dystocia in the second stage of labor?

OBJECTIVE: To estimate the rate of successful vaginal birth including operative vaginal delivery in patients with a previous cesarean for cephalopelvic disproportion in the second stage of labor. METHODS: Data from all patients who underwent trial of labor after a previous cesarean between 1990 and 2000 at our tertiary care institution were analyzed. Medical records were reviewed and data collected for the following variables: indication for the previous cesarean, birth weight and cervical dilatation at previous cesarean delivery, as well as the mode of delivery (spontaneous, vacuum, forceps, cesarean) and the birth weight for the subsequent pregnancy. Pearson's chi(2) test and one-way analysis of variance were used for statistical analyses. RESULTS: There were 2002 patients included in the study. Two hundred fourteen (11%) had their previous cesarean for dystocia in the second stage of labor, 654 (33%) for dystocia in the first stage of labor, and 1134 (57%) for other indications. The vaginal birth after cesarean success rate was 75.2% (P = .015 vs other indications), 65.6% (P < .001 vs other indications), and 82.5%, respectively. The rate of operative vaginal delivery was 15%, 12%, and 10% (P = .109). CONCLUSION: A trial of labor is reasonable in women whose previous cesarean was for dystocia in the second stage of labor. In this series, patients who underwent a trial of labor after a previous cesarean for dystocia in the second stage had 75.2% (95% confidence interval 69.5, 81.0) chance of achieving vaginal delivery.