Table 5:

Maternal and neonatal outcomes for vaginal birth after cesarean delivery for 2003–2005 versus 2012–2014, by delivery type*

OutcomeAdjusted RR (95% CI)
2003–20052012–2014
Attempted VBAC
Maternal
 Uterine rupture6.74 (4.74 to 9.58)5.47 (4.14 to 7.23)
 Uterine rupture not including dehiscence7.01 (3.71 to 13.2)9.08 (5.20 to 15.9)
 Severe morbidity1.80 (1.32 to 2.46)1.93 (1.62 to 2.30)
Neonatal
 Assisted ventilation0.91 (0.74 to 1.12)2.08 (1.84 to 2.36)
 Assisted ventilation excluding CPAP1.42 (0.96 to 2.10)3.11 (2.40 to 4.03)
 Seizures1.62 (0.81 to 3.25)2.92 (1.54 to 5.55)
 Respiratory distress syndrome0.81 (0.74 to 0.89)1.07 (0.98 to 1.18)
 Mortality and morbidity0.94 (0.77 to 1.15)2.07 (1.83 to 2.35)
 Restricted mortality and morbidity1.43 (1.01 to 2.02)2.97 (2.32 to 3.79)
Successful VBAC
Maternal
 Uterine rupture0.71 (0.33 to 1.53)0.69 (0.38 to 1.25)
 Uterine rupture not including dehiscence0.66 (0.15 to 2.95)1.30 (0.47 to 3.59)
 Severe morbidity0.81 (0.47 to 1.39)1.15 (0.89 to 1.49)
Neonatal
 Assisted ventilation0.58 (0.42 to 0.80)1.63 (1.38 to 1.92)
 Assisted ventilation excluding CPAP0.97 (0.56 to 1.69)2.30 (1.64 to 3.22)
 Seizures1.58 (0.65 to 3.84)2.61 (1.19 to 5.72)
 Respiratory distress syndrome0.60 (0.53 to 0.70)0.82 (0.72 to 0.93)
 Mortality and morbidity0.64 (0.47 to 0.86)1.64 (1.39 to 1.93)
 Restricted mortality and morbidity1.10 (0.69 to 1.76)2.26 (1.65 to 3.10)
Failed VBAC
Maternal
 Uterine rupture12.4 (8.72 to 17.7)10.3 (7.78 to 13.6)
 Uterine rupture not including dehiscence12.9 (6.81 to 24.4)17.0 (9.69 to 29.7)
 Severe morbidity2.67 (1.92 to 3.73)2.69 (2.22 to 3.25)
Neonatal
 Assisted ventilation1.22 (0.96 to 1.55)2.53 (2.19 to 2.93)
 Assisted ventilation excluding CPAP1.84 (1.19 to 2.86)3.93 (2.94 to 5.24)
 Seizures1.66 (0.72 to 3.82)3.22 (1.55 to 6.70)
 Respiratory distress syndrome1.01 (0.90 to 1.13)1.34 (1.20 to 1.49)
 Mortality and morbidity1.22 (0.97 to 1.54)2.50 (2.17 to 2.89)
 Restricted mortality and morbidity1.73 (1.17 to 2.57)3.67 (2.79 to 4.83)
  • Note: CI = confidence interval, CPAP = continuous positive airway pressure, RR = rate ratio, VBAC = vaginal birth after cesarean.

  • * Our study contrasted women with an attempted vaginal birth after cesarean delivery compared with elective cesarean delivery among women with a single prior pregnancy that resulted in a cesarean (reference group), who subsequently delivered a singleton at 37 to 43 weeks gestation in the current pregnancy in Canada (excluding Quebec) from 2003 to 2005 (n = 38 752 for maternal outcomes; n = 36 684 for neonatal outcomes) and from 2012 to 2014 (n = 55 246 for maternal outcomes; n = 51 991 for neonatal outcomes).

  • Text in boldface type indicates a statistically significant temporal change in the adjusted RR (p < 0.05).

  • Logistic models for maternal and neonatal outcomes included maternal age, diabetes mellitus, hypertension and labour induction.