OBJECTIVE: To systematically review the evidence about maternal and neonatal outcomes relating to vaginal birth after cesarean (VBAC).
DATA SOURCES: Relevant studies were identified from multiple searches of MEDLINE, DARE, and the Cochrane databases (1980 to September 2009) and from recent systematic reviews, reference lists, reviews, editorials, Web sites, and experts.
METHODS OF STUDY SELECTION: Inclusion criteria limited studies to the English-language and human studies conducted in the United States and developed countries specifically evaluating birth after previous cesarean delivery. Studies focusing on high-risk maternal or neonatal conditions, including breech vaginal delivery, or fewer than 10 patients were excluded. Poor-quality studies were not included in analyses.
TABULATION, INTEGRATION, AND RESULTS: We identified 3,134 citations and reviewed 963 articles for inclusion; 203 articles met the inclusion criteria and were quality rated. Overall rates of maternal harms were low for both trial of labor and elective repeat cesarean delivery. Although rare in both elective repeat cesarean delivery and trial of labor, maternal mortality was significantly increased for elective repeat cesarean delivery at 0.013% compared with 0.004% for trial of labor. The rates of maternal hysterectomy, hemorrhage, and transfusions did not differ significantly between trial of labor and elective repeat cesarean delivery. The rate of uterine rupture for all women with prior cesarean was 0.30%, and the risk was significantly increased for trial of labor (0.47% compared with 0.03% for elective repeat cesarean delivery). Perinatal mortality was also significantly increased for trial of labor (0.13% compared with 0.05% for elective repeat cesarean delivery).
CONCLUSION: Overall the best evidence suggests that VBAC is a reasonable choice for the majority of women. Adverse outcomes were rare for both elective repeat cesarean delivery and trial of labor. Definitive studies are lacking to identify patients who are at greatest risk for adverse outcomes.
The best evidence suggests that vaginal birth after cesarean is a reasonable choice for the majority of women.
From the Oregon Evidence-based Practice Center; the Departments of Obstetrics and Gynecology, Medical Informatics and Clinical Epidemiology, and Public Health and Preventive Medicine; the School of Nursing; and the Department of Emergency Medicine, Oregon Health & Science University, Portland, Oregon.
See related editorial on page 1112 and related article on page 1279.
Funded by the Agency for Healthcare Research and Quality, Contract No. HHSA 290-2007-10057-I, Task Order No. 4 for the Office of Medical Applications of Research at the National Institutes of Health.
The investigators thank Andrew Hamilton, MLS, MS, for conducting the literature searches and Benjamin K. S. Chan, MS, for providing statistical assistance. The authors thank Abby Parsons, MD, Edwin Reid, and Alia Broman, BA, for their assistance with the evidence report.
This article was developed based on a systematic evidence review that was conducted for and presented to the National Institutes of Health Consensus Development Conference on Vaginal Birth After Cesarean–New Insights, March 8–10, 2010, Bethesda, Maryland.
Corresponding author: Jeanne-Marie Guise, MD, MPH, Department of Obstetrics and Gynecology, Oregon Health & Science University, mail code L466, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098; e-mail:firstname.lastname@example.org.
Financial Disclosure No investigators have any affiliations or financial involvement (eg, employment, consultancies, honoraria, stock options, expert testimony, grants or patents received or pending, or royalties) that conflict with material presented in this report. The authors did not report any potential conflicts of interest.