| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
ORIGINAL RESEARCH |
From the Departments of 1Obstetrics and Gynecology, Bnai Zion Medical Center; and 2Community Medicine and Epidemiology, Faculty of Medicine, Technion, Haifa, Israel.
 |
ABSTRACT |
|---|
TOP
 ABSTRACT PATIENTS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
METHODS: We identified women with 1 previous low uterine segment cesarean who had delivered a cephalic singleton infant at gestational age 34 weeks or more from January 2000 through May 2005. Our policy is to encourage such women to undergo a trial of labor unless cesarean delivery is indicated. Unless otherwise indicated, our policy is to wait for spontaneous labor. We do not use prostaglandins, and recommend cesarean delivery if the cervix is unripe.(Bishop score < 6). We compared the outcome between women who underwent a trial of labor and women who underwent planned cesarean delivery.
RESULTS: A trial of labor was attempted by 841 women (80% successful), and 467 underwent planned cesarean delivery. Uterine rupture was observed in 1 woman 18 hours after vaginal delivery. There was no difference in major or minor maternal morbidity. There was no serious neonatal morbidity. Among the planned cesarean patients, hospital stay was longer, and there were more admissions to the neonatal intensive care unit.
CONCLUSION: With our well-defined protocol, a trial of labor after cesarean seems to be as safe for the mother and infant as planned cesarean delivery, and the hospital stay is shorter.
LEVEL OF EVIDENCE: II-2
Because we observed that the management of parturients with previous cesarean delivery in our department differs substantially from that described in the above-mentioned studies, we hypothesized that the maternal and perinatal outcome may also be different, and possibly better, because our approach seems to be more conservative or more cautious. The aim of the present investigation was to assess the risks of maternal and perinatal morbidity associated with a trial of labor as compared with repeated planned cesarean delivery in our institution.
|
PATIENTS AND METHODS |
|---|
|
TOP
ABSTRACTPATIENTS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
Our policy is to encourage all women with a prior single, low-segment cesarean delivery and a singleton cephalic gestation to undergo a trial of labor unless repeated cesarean delivery is indicated. Women are counseled regarding the risks and benefits of a trial of labor compared with elective cesarean delivery. We usually quote a VBAC success rate ranging between 60–80%, the higher figure for women with previous VBAC or previous vaginal delivery, the lower figure for women who had dystocia as the indication for the primary cesarean delivery.5 Breech presentation, estimated fetal weight of more than 4,000 g, (based on clinical and ultrasonic evaluation), unknown uterine scar, low vertical incision, inverted T incision, or any other uterine scar, as well as the patient’s request are considered indications for repeat planned cesarean delivery. In the absence of maternal or fetal indication, our policy is to wait for spontaneous labor or until 42 weeks. Whenever delivery is indicated, we consider induction only in the face of a ripe cervix (Bishop Score > 6), and prefer amniotomy to oxytocin. However, we do not use prostaglandins or Foley catheter, and recommend cesarean delivery if the cervix is unripe. We use oxytocin to augment labor when necessary. (Starting at 1.6 mU/min, with increments of 1.6 mU every 30 minutes until regular contractions, 3–4 per 10 minutes, are achieved or a maximal rate of 20 mU/min is reached.) At admission, all patients are evaluated and examined by an obstetrics and gynecology resident, who assesses whether they comply with our requirements for a trial of labor. Upon admission, 1 unit of packed blood cells is prepared at the blood bank, and intravenous infusion is started. Once in active labor, all patients are on continuous fetal monitoring. Epidural analgesia is provided upon the patient’s request. We do not perform routine manual exploration of the uterine cavity after successful VBAC.
The study included all women who had had 1 prior low-segment cesarean delivery and with a singleton pregnancy at 34.0 gestational weeks or more. The medical records for each woman were reviewed by 1 of the authors (V.N.). Demographic data, details of the obstetric history, and information about intrapartum and postpartum events were recorded. Neonatal data were collected up to discharge on all infants who were admitted to the NICU. Maternal and perinatal outcomes were compared between women who had a trial of labor and those who underwent planned repeated cesarean delivery.
Uterine rupture was defined as a disruption or tear of the uterine muscle and visceral peritoneum or a separation of the uterine muscle with extension to the bladder or broad ligament. Uterine dehiscence was defined as a disruption of the uterine muscle with intact serosa. Febrile morbidity was defined as a temperature of 38.0°C or more on at least 2 occasions at least 6 hours apart, excluding the first 24 hours after delivery. Major maternal complication was defined as the occurrence of 1 or more of the following: uterine rupture, hysterectomy, re-laparotomy, operative injury (bladder, bowel, extension of uterine excision to the cervix or to the broad ligament), transfusion of 2 or more units of blood. Minor maternal complications were defined as the occurrence of 1 or more of the following: maternal febrile morbidity, wound infection, uterine scar dehiscence, transfusion of 1 unit of blood.
All analyses were performed using the SPSS 11.5 statistical software (SPSS Inc., Chicago, IL). A 
2 test (Fisher exact test was used when appropriate) was used to examine differences between groups in categorical variables, and t test (Mann–Whitney test when appropriate) was used for continuous variables. Logistic regression was performed to adjust comparison of morbidity rate for potential confounder or modifier variables. A P value less than 0.05 was considered significant.
|
RESULTS |
|---|
|
TOP
ABSTRACTPATIENTS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
The demographic and perinatal characteristics of women and infants in the 2 groups are presented in Table 1. Compared with women who underwent planned repeated cesarean delivery, women who underwent a trial of labor were more likely to be less than 35 years old, to be of higher parity, and to have a history of prior successful vaginal birth after cesarean. Women undergoing planned cesarean delivery were delivered at an earlier gestational age and were more likely to have 1 or more pregnancy complication.
|
Maternal complications are presented in Table 2. There was only 1 case of uterine rupture among 841 women who attempted vaginal delivery after cesarean, a rate of 1.2 (95% CI 0–6.6) per 1,000. The rupture was diagnosed 18 hours after successful vaginal delivery. This patient had a normal postdelivery course for approximately 16 hours when she became hypotensive. Hematologic studies showed a fall in hematocrit and ultrasound examination revealed a large hematoma within the left broad ligament in addition to moderate amount of free fluid in the peritoneal cavity. At the laparotomy, a 4-cm-long rupture of the left uterine wall was diagnosed. The uterus was sutured and the patient had an uneventful postoperative course. One patient underwent hysterectomy after planned cesarean delivery due to placenta accreta. Relaparotomy was necessary in 1 woman after planned cesarean delivery and in 2 women after a failed trial of labor. In all 3 cases, the indication for laparotomy was postpartum hemorrhage intractable to conservative management Overall, the rate of major complications was 1.3% (95% CI 0.3–2.31) among women undergoing planned cesarean delivery compared with 1.8% (95% CI 0.9–2.7) among women attempting vaginal delivery after cesarean (P = .50). In the latter group, all but 2 of the major complications (uterine rupture and transfusion of > 2 units of blood), were associated with failed VBAC. Consequently, all of the operative injuries were diagnosed and treated during the operation. Likewise, the rate of minor complications was similar in the 2 groups. The only significant difference between the 2 groups was shorter hospital stay among women undergoing a trial of labor after cesarean. Nevertheless, for minor complications, logistic regression analysis revealed significant interaction between the group and previous vaginal delivery.(P = .045) Therefore, we analyzed for each subgroup separately. Only among women without a previous vaginal delivery, a trial of labor after a cesarean was associated with a significantly higher rate of minor complications, compared with planned repeated cesarean delivery, 7.2% compared with 3.6% (P = .03, odds ratio 2, 95% CI 1.05–4.04).
|
There were no neonatal deaths, and none of the infants suffered from hypoxic-ischemic encephalopathy. Admission to the NICU was slightly higher, but with borderline significance, among infants delivered by planned cesarean delivery (4.3% compared with 2.4%, P = .055).
Demographic and perinatal characteristics of women who had a successful or failed VBAC are presented in Table 3. Women who had a successful VBAC were of higher parity, were more likely to have had prior vaginal delivery and prior successful VBAC, were more likely to be admitted in active labor, and were less likely to need induction.
|
|
DISCUSSION |
|---|
|
TOP
ABSTRACTPATIENTS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
In the present study, there was only 1 case of uterine rupture among 841 women who attempted vaginal delivery after cesarean, a rate of 1.2 per 1,000, significantly lower than in Landon’s study (P < .04).4 There were no neonatal consequences associated with this rupture and hysterectomy was not necessary. Overall, the rates of major and minor complications were low, and no statistically or clinically significant differences were observed between the 2 groups.
The results of our study demonstrate that by limiting a trial of labor after cesarean to women with a singleton cephalic, nonmacrosomic fetus and a previous single, lower segment uterine incision, and by avoiding induction of labor in women with unfavorable cervix, the risk for uterine rupture can be markedly reduced, rendering the option of a trial of labor after cesarean to be a safe option, for both mother and infant. By waiting for the spontaneous onset of labor, not only is the risk for uterine rupture decreased but also the rate of successful VBAC is increased (Table 3). For women who wish to have larger families, the advantage of a trial of labor may be even more apparent, because multiple cesarean deliveries are associated with a higher rate of complications compared with a second cesarean delivery. Moreover, we have shown that a trial of labor after cesarean is associated with a significant reduction in maternal hospital stay. Indeed, our stringent patient selection reduces the number of women eligible for a trial of labor after cesarean; nevertheless, when the legitimacy of a trial of labor after cesarean is at stake, a limited number of trials of labor in a selected population seems to be preferable to utterly banning a trial of labor after cesarean to all.
We recognize that our study has 2 limitations: first, because it is a retrospective study, it is nonrandomized. Second, the number of patients is relatively small. However, with power of about 80%, the sample size was able to detect 3- and 2-fold increase in the rate of major and minor complications, corresponding with differences of only 2.5% and 3.6%, respectively. Nevertheless, we believe that our results are relevant, because they describe the outcome associated with the implementation of a well-defined, strict management protocol in a single institution, with almost no deviation from that protocol.
In conclusion, we have shown that with our well-defined protocol, a trial of labor after cesarean seems to be as safe for the mother and infant as planned cesarean delivery and is associated with a shorter hospital stay. We encourage others to evaluate our approach further and hope that if larger studies do corroborate our results, the dictum "once a cesarean always a cesarean" will continue to be a thing of the past.
|
Footnotes |
|---|
doi:10.1097/01.AOG.0000197062.82735.f6
|
REFERENCES |
|---|
|
TOP
ABSTRACTPATIENTS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
2. McMahon MJ, Luther ER, Bowes WA, Olshan AF. Comparison of a trial of labor with an elective second cesarean section. N Engl J Med 1996;335:689–95.
3. Lydon-Rochelle M, Holt VL, Easterling TR, Martin DP. Risk of uterine rupture during labor among women with one prior cesarean delivery. N Engl J Med 2001;345:3–8.
4. 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;351:2581–9.
5. Gonen R, Tamir A, Degani S, Ohel G. Variables associated with successful vaginal birth after one cesarean section: a proposed vaginal birth after cesarean section score. Am J Perinatol 2004;21:447–53.[Medline]
6. Sachs BP, Kobelin C, Castro MA, Frigoletto F. The risks of lowering the cesarean-delivery rate. N Engl J Med 1999;340:54–7.
7. Asakura H, Myers SA. More than one previous cesarean delivery: a 5-year experience with 435 patients. Obstet Gynecol 1995;85:924–9.[Abstract]
8. Caughey AB, Shipp TD, Repke JT, Zelop CM, Cohen A, Lieberman E. Rate of uterine rupture during a trial of labor in women with one or two prior cesarean deliveries. Am J Obstet Gynecol 1999;181:872–6.[Medline]
9. Vaginal birth after previous cesarean delivery. ACOG Practice Bulletin No.54. American College of Obstetricians and Gynecologists. Obstet Gynecol 2004;104:203–11.
10. Ananth CV, Smulian JC, Vintzileos AM. The association of placenta previa with history of cesarean delivery and abortion: a metaanalysis. Am J Obstet Gynecol 1997;177:1071–8.[Medline]
11. Mankuta DD, Leshno MM, Menasche MM, Brezis MM. Vaginal birth after cesarean section: trial of labor or repeat cesarean section? A decision analysis. Am J Obstet Gynecol 2003;189:714–9.[Medline]
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
