The counselling of patient with prior C-section

A trial of labor after prior cesarean delivery is associated with a greater perinatal risk than is elective repeated cesarean delivery without labor, although absolute risks are low. Information and counselling aim to estimate specific risks and to balance these risks according to individual factors. Therefore, the physician has to answer two questions: (i) which would be the probability of successful vaginal delivery? (ii) which would be the risk of uterine rupture with a trial of labor? The risk factors for failure of trial of labor are: increased maternal age, obesity, and fetal macrosomia. The risk factors for uterine rupture are: increased maternal age, postpartum fever after the previous cesarean delivery, short interdelivery interval, history of at least two previous cesarean deliveries, and a history of classical incision. Conversely, other factors are of good prognosis: a prior vaginal delivery and, particularly, a prior VBAC (Vaginal Birth After Caesarean) are associated with a higher rate of successful trial of labor compared with patients with no prior vaginal delivery; ultrasonographic measurement of the lower uterine segment thickness>3.5 mm has an excellent negative predictive value for the risk of uterine defect. Finally, the wish for additional pregnancies following a cesarean section must be considered as an argument in favour of a trial of labor after accounting for the increasing risks correlated with repeated elective cesarean deliveries.     

Balancing the risks of planned cesarean section and trial of vaginal delivery for the mature, selected, singleton breech presentation

The experience of mature, singleton, vaginal breech delivery over the last decade in our hospital is reviewed. This constitutes the largest series of breech delivery reported for over twelve years. Unlike all but two previous reports, we analyze our results by management policy; elective cesarean section, trial of vaginal breech delivery and cesarean section as soon as the diagnosis of breech delivery was made on labor ('expedite' cesarean operations). Six intrapartum or neonatal deaths occurred among 613 patients selected for trial of vaginal delivery--a rate of one per cent. There were none following 217 elective or 69 expedite cesarean sections. A detailed review of the literature over the last decade confirms that trial of vaginal delivery is more dangerous to the fetus and results in about one perinatal death of a normally formed infant in 200 deliveries. Apgar scores were slightly lower following trial of vaginal delivery and there were more irritable or injured babies in this group. The last intrapartum or neonatal death occurred in 1981. However, the elective cesarean section rate has increased from 14 to 33 per cent over this time period. Similarly the rate of failed trial of vaginal breech delivery has increased from 15 to 31 per cent. The proportion of failed trials was highest where the fetus was large but clinicians were poor at estimating fetal weight. Decision theory is used to examine the maternal utility of trial of vaginal breech delivery versus elective cesarean section when the intrapartum cesarean rate rises to these levels. It is shown that, from the point of view of maternal mortality and morbidity in the current pregnancy, trial of vaginal delivery maybe the more dangerous maternal option. Thus a low threshold for cesarean section in labor leads to greater fetal safety at the mother's expense. It is nevertheless concluded that maternal attitude and the long-term effects of a uterine scar should be considered in the final decision.     

Effect of previous vaginal delivery on the risk of uterine rupture during a subsequent trial of labor

OBJECTIVE: We examined the effect of prior vaginal delivery on the risk of uterine rupture in pregnant women undergoing a trial of labor after prior cesarean delivery. STUDY DESIGN: The medical records of all pregnant women with a history of cesarean delivery who attempted a trial of labor during a 12-year period at a single center were reviewed. For the current analysis, the study population was limited to term pregnancies. The effect of previous vaginal delivery on the risk of uterine rupture during a subsequent trial of labor was evaluated. Separate analyses were performed for women with a single previous cesarean delivery and for those with >1 prior cesarean delivery. For each of these subgroups, the rate of uterine rupture among women who had > or =1 prior vaginal delivery was compared with the rate among women with no prior vaginal delivery. Logistic regression analysis was used to examine the associations with control for confounding factors. RESULTS: Of 3783 women with 1 prior scar, 1021 (27.0%) also had > or =1 prior vaginal delivery. During a subsequent trial of labor, the rate of uterine rupture was 1.1% among pregnant women without prior vaginal delivery and 0.2% among pregnant women with prior vaginal delivery (P =.01). Logistic regression analysis controlling for duration of labor, induction, birth weight, maternal age, year of birth, epidural analgesia, and oxytocin augmentation indicated that, among women with a single scar, those with a prior vaginal delivery had a risk of uterine rupture that was one fifth that of women without a previous vaginal delivery (odds ratio, 0.2; 95% confidence interval, 0.04-0.8). In the group of 143 pregnant women with >1 previous cesarean delivery, women with a prior vaginal delivery had a somewhat lower risk of uterine rupture (3.9% vs 2.5%; adjusted odds ratio, 0.6; 95% confidence interval, 0.01-6.7). This difference was not statistically significant. CONCLUSION: Among women with 1 prior cesarean delivery undergoing a subsequent trial of labor, those with a prior vaginal delivery were at substantially lower risk of uterine rupture than women without a previous vaginal delivery.     

Is vaginal birth after two or more cesarean sections safe?

Fifty-five patients with a history of two or more cesarean sections underwent a trial of labor. Forty-two had had previous uterine incisions of unknown type, 11 had had low cervical transverse incisions, and two had had low vertical incisions. Twenty-five women (45%) had successful vaginal deliveries, and 30 (55%) received oxytocin augmentation of labor. The incidence of vaginal delivery was significantly lower in patients who required oxytocin augmentation (30 versus 64%, P less than .01). Three of the 55 patients had scar separation detected at the time of delivery. Two patients underwent hysterectomy. There were no maternal or neonatal deaths. A history of multiple cesarean sections need not exclude the patient from the option of trial of labor.     

Delivery after previous cesarean: a risk evaluation. Swiss Working Group of Obstetric and Gynecologic Institutions

OBJECTIVE: To examine the risks of vaginal delivery after previous cesarean and to find criteria to help decide whether a trial of labor or an elective repeat cesarean should be preferred. METHODS: We evaluated 29,046 deliveries after previous cesarean registered in a pooled database of 457,825 deliveries used to assess quality control in gynecology and obstetrics departments in Switzerland. RESULTS: Among the 17,613 trial-of-labor cases logged (attempt rate 60.64%), the success rate was 73.73% (65.56% after inducing labor and 75.06% after the spontaneous onset of labor). The following complications were significantly more frequent in the previous-cesarean group: maternal febrile episodes (relative risk [RR] 2.77; 95% confidence interval [CI] 2.52, 3.05), thromboembolic events (RR 2.81; CI 2.23, 3.55), bleeding due to placenta previa during pregnancy (RR 2.06; CI 1.70, 2.49), uterine rupture (92 cases; RR 42.18; CI 31.09, 57.24), and perinatal mortality (118 cases, including six associated with uterine rupture; RR 1.33; CI 1.10, 1.62). The postcesarean group also showed a 0.28% rate of peripartum hysterectomy (81 cases; RR 6.07; CI 4.71, 7.83). There was one maternal death in the group, compared with 14 maternal deaths in the group without previous cesarean (no statistical significance). The risk of uterine rupture for patients with previous cesareans was elevated in the trial-of-labor group compared with the group without trial of labor (RR 2.07; CI 1.29, 3.30), but all other maternal risks, including peripartum hysterectomy (RR 0.36; CI 0.23, 0.56), were lower. When comparing the women having a trial of labor, the 70 with uterine rupture more often had induced labor (24.29% compared with 13.92% in the nonrupture group; P = .013), had epidural anesthesia (24.29% compared with 8.44%; P < .001), had an abnormal fetal heart rate tracing (32.86% compared with 8.53%; P < .001), and had failure to progress (21.43% compared with 7.98%; P = .001). CONCLUSION: A history of cesarean delivery significantly elevates the risks for mother and child in future deliveries. Nonetheless, a trial of labor after previous cesarean is safe. Induction of labor, epidural anesthesia, failure to progress, and abnormal fetal heart rate pattern are all associated with failure of a trial of labor and uterine rupture.     

Elective repeat cesarean delivery versus trial of labor: a meta-analysis of the literature from 1989 to 1999

OBJECTIVE: The aim of this study was to compare a trial of labor with elective repeat cesarean delivery among women with previous cesarean delivery. STUDY DESIGN: We searched MEDLINE and EMBASE databases from 1989 through 1999 with the following terms: vaginal birth after cesarean delivery, trial of labor, trial of scar, and uterine rupture. We included all controlled trials from developed countries in which the control group had been eligible for a trial of labor. Outcomes of interest were uterine rupture, hysterectomy, maternal febrile morbidity, maternal mortality, 5-minute Apgar score <7, and fetal or neonatal mortality. We computed pooled odds ratios for each outcome. RESULTS: The search strategy identified 52 controlled studies, 37 of which were excluded because many of the control subjects were not eligible for a trial of labor. Fifteen studies with a total of 47,682 women were included. Uterine rupture occurred more frequently among women undergoing a trial of labor than among those undergoing elective repeat cesarean delivery (odds ratio, 2.10; 95% confidence interval, 1.45-3.05). There was no difference in maternal mortality risk between the 2 groups (odds ratio, 1.52; 95% confidence interval, 0.36-6.38). Fetal or neonatal death (odds ratio, 1.71; 95% confidence interval, 1.28-2.28) and 5-minute Apgar scores <7 (odds ratio, 2.24; 95% confidence interval, 1.29-3.88) were more frequent in the trial of labor group than in the control group. Mothers undergoing a trial of labor were less likely to have febrile morbidity (odds ratio, 0.70; 95% confidence interval, 0.64-0.77) or to require transfusion (odds ratio, 0.57; 95% confidence interval, 0.42-0.76) or hysterectomy (odds ratio, 0.39; 95% confidence interval, 0.27-0.57). CONCLUSION: A trial of labor may result in small increases in the uterine rupture rate and in fetal and neonatal mortality rates with respect to elective repeat cesarean delivery. Maternal morbidity, including febrile morbidity, and the need for transfusion or hysterectomy may be reduced with a trial of labor.     

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.     

VAGINAL BIRTH AFTER CESAREAN IN A HOSPITAL-BASED BIRTH CENTER STAFFED BY CERTIFIED NURSE-MIDWIVES

The efficacy and safety of a trial of labor after previous cesarean were evaluated in selected, low-risk women in a hospital-based birthing center staffed by certified nurse-midwives. A total of 303 low-risk women with one previous cesarean delivery underwent a trial of labor in the birthing center. A matched control, without a previous uterine incision, was selected for each study patient. Hospital charts of 298 matched pairs were available for analysis. Outcome measures included the requirement for intrapartum transfer to medical management, use of oxytocin, method of delivery, uterine scar separation, Apgar scores, birth weights, maternal febrile morbidity, and length of hospital stay. Intrapartum transfer to medical management was necessary in 26 (8.7%) study patients and 31 (10.4%) control subjects. The overall rate (98.3%) of vaginal birth after cesarean among study patients was not statistically different from the vaginal birth rate (99.3%) among control subjects. There were no differences in maternal or neonatal morbidity. The high percentage (84%) of study patients having had a previous uncomplicated vaginal birth after cesarean must be considered a potential limitation of the outcome data; however, the overall vaginal birth rate between study patients with and study patients without previous vaginal birth after cesarean was not statistically different. The latter group was more likely to require transfer to medical management and/or oxytocin augmentation. On the basis of these results, we concluded that for selected, low-risk patients, a trial of labor after one previous cesarean may be managed safely and effectively by certified nurse-midwives in a hospital setting.     

Vaginal birth after cesarean

Allowing a woman with a previous cesarean birth a trial of labor rather than performing an elective repeat cesarean section continues to be a controversial area in obstetrics today. In an effort to evaluate the risks associated with a trial of labor, a prospective investigation was undertaken from July 1, 1982, through June 30, 1984. During the first year of the study, patients with a known vertical scar or more than one prior cesarean birth were excluded from an attempted trial of labor. Beginning July 1, 1983, patients with two prior cesarean births were no longer excluded and were studied prospectively. During this 2-year period, 32,854 patients were delivered of their infants at the Los Angeles County/University of Southern California Medical Center. Of these patients, 2708 (8.2%) had undergone a prior cesarean birth, and 1796 women (66%) underwent a trial of labor. A total of 1465 (81%) of them achieved a vaginal delivery. Successful vaginal delivery by the number of prior cesarean sections was as follows: one, 82%; two, 72%; three, 90%. When contrasted with the group without a trial of labor, the group with a trial of labor had significantly less maternal morbidity. In a comparison of the groups with and without a trial of labor, the incidence of uterine dehiscence (1.9% versus 1.9%) and rupture (0.3% versus 0.5%) was similar. With the application of attempted vaginal delivery in our patients with a previous cesarean birth, we were able to reduce our cesarean delivery rate for this population alone by 54%. In summary, the benefits associated with a trial of labor in the patient with a prior cesarean birth far outweigh the risks. The policy of "once a cesarean section, always a cesarean section" should be abandoned.     

Unknown uterine scar and trial of labor

A review of 393 patients undergoing trial of labor after one or more previous cesarean sections was performed. Three hundred patients had an unknown uterine scar, 88 patients had a documented low cervical transverse incision, and five patients had a prior low vertical incision. The rate of vaginal delivery and maternal and fetal morbidity was no different in those patients with an unknown prior uterine incision compared with those having a known prior low cervical transverse incision. In 66 of the patients with a documented low cervical transverse incision, the original operative record was reviewed in regard to single-layer closure of the uterine incision versus double-layer closure or imbricating technique. No patient with a double-layer uterine closure had a subsequent dehiscence, whereas three patients with a prior single-layer closure exhibited scar separation. These data suggest that neither an unknown scar nor a single-layer uterine closure places the mother or fetus at greater risk.     

Cervical ripening with transcervical foley catheter and the risk of uterine rupture

OBJECTIVE: To estimate whether the rate of uterine rupture in patients with a previous cesarean delivery is related to labor induction and/or cervical ripening using transcervical Foley catheter. METHODS: Charts of all patients who had a trial of labor after a previous cesarean delivery in our institution between 1988 and 2002 were reviewed. The rates of successful vaginal birth after cesarean delivery and uterine rupture in patients with spontaneous labor (control group) were compared with those of patients who underwent a labor induction by means of amniotomy with or without oxytocin and patients who underwent a labor induction/cervical ripening using a transcervical Foley catheter. Logistic regression analysis was performed to adjust for confounding variables. RESULTS: Of 2479 patients, 1807 had a spontaneous labor, 417 had labor induced by amniotomy with or without oxytocin, and 255 had labor induced by using transcervical Foley catheter. The rate of successful vaginal birth after cesarean delivery was significantly different among the groups (78.0% versus 77.9% versus 55.7%, P <.001), but not the rate of uterine rupture (1.1% versus 1.2% versus 1.6%, P =.81). After adjusting for confounding variables, the odds ratio (OR) for successful vaginal birth after cesarean delivery was 0.68 (95% confidence interval [CI] 0.41, 1.15), and the OR for uterine rupture was 0.47 (95% CI 0.06, 3.59) in patients who underwent an induction of labor using a transcervical Foley catheter when compared with patients with spontaneous labor. CONCLUSION: Labor induction using a transcervical Foley catheter was not associated with an increased risk of uterine rupture.     

Twice a cesarean, always a cesarean?

The cesarean delivery rate has quadrupled during the past two decades, resulting in considerable attention focused on alternatives to cesarean birth. One option, vaginal birth after one previous cesarean, has come to be recognized as an acceptable alternative to routine elective repeat cesarean delivery. The purpose of this report was to evaluate whether women with two previous cesareans can safely undergo a trial of labor. Between July 1, 1982 and June 30, 1986, data were collected prospectively on all women with previous cesareans. Those with a known classical incision or a medical or obstetric contraindication to a trial of labor were excluded from an attempted vaginal delivery. During this period, 67,784 patients were delivered, of whom 6250 (9.2%) had had a previous cesarean. Of the 6250 previous-cesarean patients, 1088 (17.4%) had had two previous cesareans; of these, 501 (46%) underwent a trial of labor and 346 (69%) delivered vaginally. Whereas the overall rate of uterine dehiscence was 3%, the rate in those women who attempted a vaginal delivery was 1.8%, versus 4.6% in those who did not. Overall, oxytocin was used in 284 (57%) and was associated with a dehiscence rate of 2.1%, versus 1.4% in the no-oxytocin group. Successful vaginal delivery was related significantly to the use of oxytocin and to a previous vaginal delivery. Trial of labor in patients with two previous cesareans appears to be a reasonable consideration.     

Uterine rupture with the use of PGE2 vaginal inserts for labor induction in women with previous cesarean sections

OBJECTIVE: To analyze the rate of uterine rupture in women with previous cesarean sections undergoing a trial of labor in which a prostaglandin E2 (PGE2) vaginal insert was used. STUDY DESIGN: The study was based on a computerized search and review of pharmacy records, medical records and the pertinent literature. Pharmacy records were correlated with the medical records of all women undergoing a trial of labor after cesarean section over a 33-month period. RESULTS: Between January 1998 and September 2000, 13,544 patients delivered. Of these cases, 790 were vaginal trials of labor after previous cesarean section. A PGE2 vaginal insert was used in 58 of the patients. A total of 6 of these 58 patients (10.3%) experienced uterine rupture. This compares to a rupture rate of 1.1% (8/732) in deliveries not using PGE2 vaginal inserts. CONCLUSION: The risk of uterine rupture was significantly increased in patients undergoing a trial of labor after previous cesarean section when a PGE2 vaginal insert was used. Physicians need to be aware that using a PGE2 vaginal inserts for cervical ripening and/or induction of labor in women with a previous cesarean section might increase the risk of uterine rupture above the standard risk for vaginal birth after cesarean (VBAC) candidates. We recommend that all VBAC patients using a PGE2 vaginal insert be closely monitored for evidence of uterine rupture.     

Trial of labor after 2 cesarean sections. Prospective study of 130 cases

The mode of delivery in the parturient women with two prior cesarean is controversial. Based on a prospective analysis of 130 cases, we tried to assess the outcome of trial of labor after two cesarean sections. Among 167 patients with two uterine scars, 130 (77.8%) were selected for a trial of labor that was successful in 65 cases (50%). The overall rate of vaginal birth and cesarean section was 39% and 61%, respectively. There were 4 scar dehiscences and 2 uterine ruptures among the women who underwent trial of labor, but no case of perinatal death or morbidity related to these complications was observed. In the majority of the cases, these scar separations were due to poor obstetrical conditions. Trial of vaginal delivery after two prior cesarean sections seems to us a reasonable attitude if it is well indicated and supervised correctly.     

Previous preterm cesarean delivery: identification of a new risk factor for uterine rupture in VBAC candidates.

OBJECTIVE: A major risk of trials of labor in patients with prior cesarean delivery is uterine rupture. We evaluated the question of whether a previous cesarean delivery at an early gestational age predisposes the patient to subsequent uterine rupture. METHODS: This was a retrospective chart review of patients delivering at North Shore University Hospital with a trial of labor after previous cesarean delivery to ascertain all cases of uterine rupture. Patients who had had a previous cesarean delivery at our institution who did not suffer uterine rupture during a trial of labor served as controls. RESULTS: Twenty-five patients suffered a uterine rupture. The incidence of prior preterm cesarean delivery (PPCD) in this group was 40%, compared to 10.9% of 691 laboring vaginal birth after cesarean (VBAC) patients without rupture (p < 0.001). Patients in the rupture group with a PPCD were less likely to have experienced labor in the index pregnancy and more likely to have had an interdelivery interval of less than two years. CONCLUSIONS: An undeveloped lower segment in the preterm uterus represents a risk for later rupture, even if the incision is transverse.     

Association between prior vaginal birth after cesarean and subsequent labor outcome

Objective: To estimate the effect of prior successful vaginal birth after cesarean (VBAC) on the rate of uterine rupture and delivery outcome in women undergoing labor after cesarean.

Methods: A retrospective cohort study of all women attempting labor after cesarean delivery in a university-affiliated tertiary-hospital (2007–2014) was conducted. Study group included women attempting vaginal delivery with a history of cesarean delivery and at least one prior VBAC. Control group included women attempting first vaginal delivery following cesarean delivery. Primary outcome was defined as the rate of uterine rupture. Secondary outcomes were delivery and maternal outcomes.

Results: Of 62,463 deliveries during the study period, 3256 met inclusion criteria. One thousand two hundred and eleven women had VBAC prior to the index labor and 2045 underwent their first labor after cesarean. Women in the study group had a significantly lower rate of uterine rupture 9 (0.7%) in respect to control 33 (1.6%), p?=?.036, and had a higher rate of successful vaginal birth (96 vs. 84.9%, p?p?=?.04).

Conclusions: In women attempting labor after cesarean, prior VBAC appears to be associated with lower rate of uterine rupture and higher rate of successful vaginal birth.     

Obstetric outcome of patients with more than one previous cesarean section

Records of patients with more than one previous cesarean section were reviewed for a 1-year period. Of 69 such pregnancies, 36 underwent trial of labor in concurrence with an ongoing departmental cesarean section reduction initiative; 80% culminated in vaginal delivery. Twenty of these 69 patients had three or more previous cesarean sections; 9 underwent trial of labor, with 8 subsequent vaginal deliveries. The vaginal delivery rate after more than one previous cesarean section was no different from that of patients with only one previous cesarean section. We conclude that trial of labor in patients with more than one previous cesarean section did not result in a deleterious outcome. Our findings suggest that a trial of labor after more than one previous cesarean section delivery can safely be allowed. Guidelines can be identical to those already established for patients with only one previous cesarean section.     

Population adjustment of the definition of the vaginal birth after cesarean rate

OBJECTIVE: The vaginal birth after cesarean delivery rate is calculated with a denominator equal to the number of all women who give birth after a previous cesarean delivery, including those who are not candidates for a trial of labor. We evaluated the impact of adjustment for noncandidates for a trial of labor on vaginal birth after cesarean delivery rates. STUDY DESIGN: All women with a previous cesarean delivery who were delivered during 1998 were classified as either candidates or noncandidates for a trial of labor. An adjusted vaginal birth after cesarean delivery rate was calculated by eliminating noncandidates for a trial of labor from the denominator. The percentage of noncandidates for a trial of labor, the vaginal birth after cesarean delivery rate, and the adjusted vaginal birth after cesarean delivery rate were compared among 3 clinical services. RESULTS: The maternal-fetal medicine service had a significantly higher percentage of noncandidates for a trial of labor than did either the low-risk resident clinic or the low-risk private service. The maternal-fetal medicine service had a significantly lower vaginal birth after cesarean delivery rate than did the private service, but this difference was no longer present after application of an adjusted vaginal birth after cesarean delivery definition. CONCLUSION: For accurate comparison of vaginal birth after cesarean delivery rates among providers it is essential to account for patient risk status in the vaginal birth after cesarean delivery definition through the elimination of noncandidates for a trial of labor.     

Trial of labor after one previous cesarean delivery for multifetal gestation

OBJECTIVE: To estimate success rates and risks with a trial of labor after one previous cesarean delivery for multifetal gestation compared with one previous cesarean delivery for a singleton pregnancy. METHODS: Patients from the National Institute of Child Health and Human Development Maternal Fetal Medicine Units Network Cesarean Registry with one previous cesarean delivery and a current term singleton pregnancy were identified. Cases had one previous cesarean delivery for a multifetal pregnancy. Controls had one previous cesarean delivery for a singleton pregnancy. RESULTS: Of cases, 556 of 944 (58.9%) attempted a trial of labor. Of controls, 13,923 of 29,329 (47.5%) attempted a trial of labor. The trial of labor success rate was 85.6% among cases and 73.1% among controls (odds ratio 2.19, 95% confidence interval 1.72-2.78). Compared with trial of labor controls, cases had no statistically increased risk of transfusion, endometritis, intensive care unit admissions, uterine rupture, or perinatal complications. Cases in this analysis with a successful trial of labor were more likely to have previously had a successful vaginal birth after cesarean (37.1% compared with 14.1%, P<.001). CONCLUSION: Women with one previous cesarean delivery for a multifetal gestation have high trial of labor success rates and low complication rates.     

Management of previous cesarean section

PURPOSE OF REVIEW: The management of cesarean sections causes much controversy among healthcare providers, patients, and insurers. A trial of vaginal birth after previous cesarean is reported to be a safe and practical method to reduce the rate of cesarean sections. The popularity of vaginal birth after previous cesarean has increased over the past two decades, but rates have recently started to decline again. This review will evaluate recent literature that might be responsible for this reversal in trend. RECENT FINDINGS: Earlier studies on previous cesarean section pregnancies focused primarily on the success rate of vaginal birth after previous cesarean, which is reported to be 60-80%. Recent large, retrospective, population-based cohort studies examined the maternal and neonatal safety of trial of labour compared with elective repeat cesarean delivery, and confirmed that the risks of uterine rupture and neonatal mortality were significantly increased after trial of labour, particularly when induced with prostaglandins. However, the absolute risk of adverse events remains small. The maternal and neonatal morbidity risk increases when vaginal birth after previous cesarean attempts fails, which emphasizes the importance of careful case selection. SUMMARY: Recent studies highlighted the risks of attempted vaginal birth after previous cesareans, especially when trials fail, but have not addressed the long-term risks of an elective repeat cesarean delivery. The assessment of treatment risks by observational studies is subject to bias, because the different treatment groups may not be comparable at the outset. In the absence of better data, the counselling of such women must currently be based on this evidence.