TY - JOUR T1 - Maternal and newborn outcomes after a prior cesarean birth by planned mode of delivery and history of prior vaginal birth in British Columbia: a retrospective cohort study JF - CMAJ Open SP - E158 LP - E165 DO - 10.9778/cmajo.20140055 VL - 3 IS - 2 AU - Celeste D. Bickford AU - Patricia A. Janssen Y1 - 2015/04/02 UR - http://www.cmajopen.ca/content/3/2/E158.abstract N2 - Background As rates for cesarean births continue to rise, more women are faced with the choice to plan a vaginal or a repeat cesarean birth after a previous cesarean. The objective of this population-based retrospective cohort study was to compare the safety of planned vaginal birth with cesarean birth after 1–2 previous cesarean sections. Methods We identified singleton term births in British Columbia from 2000 to 2008 using data from the British Columbia Perinatal Data Registry. Women carrying a singleton fetus in cephalic presentation at term (37–41 weeks of gestation completed) with 1–2 prior cesarean births were included. Those with gestational hypertension, pre-existing diabetes and cardiac disease were excluded. Maternal and neonatal outcomes were classified as either life-threatening or non–life threatening. We compared outcomes among women with none versus at least 1 previous vaginal birth, by planned method of delivery. We estimated relative risks (RR) and 95% confidence intervals (CI) for composite outcomes using Poisson regression. Results Of the 33 812 women in the sample, 5406 had a history of vaginal delivery and 28 406 did not. The composite risk for life-threatening maternal outcomes was elevated among women planning vaginal compared with cesarean birth both with and without a prior vaginal birth (RR 2.06, 95% CI 1.20–3.52) and (2.52, 95% CI 2.04–3.11). Absolute differences (attributable risk [AR]) were 1.01% and 1.31% respectively. Non–life threatening maternal outcomes were decreased among women planning a vaginal birth if they had had at least 1 prior vaginal delivery (RR 0.51, 95% CI 0.33–0.77; AR 1.17%). The composite risk of intrapartum stillbirth, neonatal death or life-threatening neonatal outcomes did not differ among women planning vaginal or cesarean birth with a prior vaginal delivery and non–life threatening neonatal outcomes were decreased, (RR 0.67, 95% CI 0.52–0.86); AR 1.92%). Interpretation After 1 or 2 previous cesarean births, risks for adverse outcomes between planned vaginal and cesarean birth are reduced among women with a prior vaginal birth. Our data offer women and their health care providers the opportunity to consider risk profiles separately for women who have and have not had a prior vaginal delivery. ER -