New research to be published in BJOG: An International Journal of Obstetrics and Gynaecology has found that women with three or more prior caesareans who attempt vaginal birth have similar rates of success and risk for maternal morbidity as those with one prior caesarean, and similar overall morbidity (adding vaginal births and emergency caesareans together) as those delivered by elective repeat caesarean.
Planned vaginal birth after caesarean (VBAC) refers to any woman who has experienced a prior caesarean birth who intends to try for a vaginal birth rather than to deliver by elective repeat caesarean. Although relatively low complication rates, including uterine rupture, have been demonstrated among women with two prior low-transverse caesareans who attempt vaginal birth, there are very limited data available on outcomes among women with more than two prior caesareans. Neither the American College of Obstetricians and Gynaecologists (ACOG) nor the Royal College of Obstetricians and Gynaecologists (RCOG) currently recommend planned VBAC attempt in women with three or more prior caesarean deliveries1.
In this study, the researchers sought to estimate the rate of success and risk of maternal morbidity in women with three or more prior caesareans who attempt VBAC. The study reviewed multi-centre data from 17 tertiary and community delivery centres in the Northeastern United States from 1996 to 2000. A total of 25,005 women who had a least one prior caesarean delivery were included.
The findings indicate that women with three or more prior caesarean deliveries did not experience a difference in morbidity based on whether they attempted VBAC or elected for a repeat caesarean. The 89 women with three or more prior caesareans who attempted VBAC were as likely to be successful as women with one or two prior caesareans, 79.8% compared to 75.5% and 74.6% respectively. In addition, none of them experienced significant maternal morbidity such as uterine rupture, uterine artery laceration, and bladder or bowel injury.
The authors suggest that, given the findings, precluding VBAC for all women with three or more prior caesareans may not be evidence based. Although there is a measurable maternal morbidity associated with delivery for a woman with a history of three or more prior caesareans, it does not differ significantly by mode of delivery. Risks associated with multiple caesareans are several, including surgical morbidity and abnormal placentation in future pregnancies.
Lead author, Dr. Alison Cahill, from the Department of Obstetrics and Gynaecology at Washington University in St. Louis School of Medicine, said “These data suggest that women with three or more prior caesareans who attempt VBAC have similar rates of success and risk for maternal morbidity as those with one or two prior caesareans, and along with other publications, suggest that perhaps it is time to revisit the current recommendations for VBAC attempts for women with more than one prior caesarean”.
“Many have proposed a ‘conservative’ approach to VBAC attempts, which we agree is prudent. But our evidence does not suggest that a conservative approach, which we interpret as one that aims to reduce morbidity - and specifically the risk of uterine rupture - is necessarily achieved by allowing VBAC attempts only in women with one prior caesarean. Given appropriate patient selection, VBAC following two or even three previous caesareans in certain cases may be reasonably safe.”
Prof. Philip Steer, BJOG editor-in-chief, said “Although confidence in the findings of the study is limited by the relatively small sample size of women who have had three previous caesareans, these findings provide additional information for women, and contribute to the available evidence on VBAC success and safety in women with more than one prior caesarean.
“As childbirth does not always ‘follow the plan’, the results may also serve as a useful reference for clinicians when a women with three or more prior caesareans presents in spontaneous labour.”
BJOG: An International Journal of Obstetrics and Gynaecology is owned by the Royal College of Obstetricians and Gynaecologists (RCOG) but is editorially independent and published monthly by Wiley-Blackwell. The journal features original, peer-reviewed, high-quality medical research in all areas of obstetrics and gynaecology worldwide. Please quote ‘BJOG' or ‘BJOG: An International Journal of Obstetrics and Gynaecology' when referring to the journal and include the website: www.bjog.org as a hidden link online.
Cahill A. Tuuli M, Odibo A, Stamilio D, Macones G. Vaginal birth after caesarean for women with three or more prior caesareans: assessing safety and success. BJOG 2010; DOI: 10.1111/j.1471-0528.2010.02498.x.
To view an abstract of the paper, click here (http://dx.doi.org/10.1111/j.1471-0528.2010.02498.x.)
1 American College of Obstetricians and Gynecologists (ACOG). Practice Bulletin #54: Vaginal birth after previous cesarean. Obstet Gynecol 2004;104:203–12; Royal College of Obstetricians and Gynaecologists (RCOG) Green-top Guideline No.45, Birth After Previous Caesarean Birth (February 2007) available online at http://www.rcog.org.uk/womens-health/clinical-guidance/birth-after-previous-caesarean-birth-green-top-45.