| Variable | Unsuccessful VBAC (n = 224) | Successful VBAC (n = 342) | P-value | ||
| Age (years) | 32.0 ± 5.4 | 32.1 ± 5.1 | 0.974 | ||
| BMI (kg/m2) | 34.7 ± 7.3 | 33.5 ± 6.5 | 0.046* | ||
|
| Average (18.5 to <25) | 17 (7.6%) | 24 (7%) | 0.004* | |
|
| Overweight (25.0 to <30) | 47 (21%) | 68 (19.9%) | ||
|
| Category I obesity (30 to <35) | 48 (21.4%) | 123 (36%) | ||
|
| Category II obesity (35 to <40) | 63 (28.1%) | 82 (24%) | ||
|
| Category III obesity (40 or higher) | 49 (21.9%) | 45 (13.2%) | ||
| Parity | 1 (1 - 4) | 2 (1 - 4) | 0.006* | ||
| Prior VBAC | 47 (21%) | 163 (47.7%) | 0.000* | ||
| Number of prior VBAC | 0 (0-0) | 0 (0-1) | 0.000* | ||
| Prior vaginal delivery | 99 (44.2%) | 200 (58.5%) | 0.001* | ||
| Indication of previous cesarean |
|
| 0.000* | ||
|
| Fetal distress | 92 (41.1%) | 187 (54.7%) |
| |
|
| Failed progress | 53 (23.7%) | 38 (11.1%) |
| |
|
| Failed induction of labour | 9 (4%) | 8 (2.3%) |
| |
|
| Malpresentation | 48 (21.4%) | 89 (26%) |
| |
|
| Multifetal pregnancy | 6 (2.7%) | 13 (.8%) |
| |
|
| Antepartum hemorrhage | 16 (7.1%) | 7 (2%) |
| |
| Interval from last cesarean (years) | 4 ± 3.1 | 5.1 ± 3.6 | 0.000* | ||
| Antenatal care visits | 5 (2 - 7) | 5 (2 - 7) | 0.652 | ||
| Associated medical disorders | 59 (26.3%) | 62 (18.1%) | 0.021* | ||
| Onset of labour |
|
| 0.542 | ||
|
| Spontaneous | 207 (92.4%) | 310 (90.6%) |
| |
|
| Induced | 17 (7.6%) | 32 (9.4%) |
| |
| Premature rupture of membranes | 45 (20.1%) | 74 (21.6%) | 0.675 | ||
| Meconium stained liquor | 20 (8.9%) | 11 (3.2%) | 0.004* | ||
| Delivery gestational age (weeks) | 38.2 ± 2.3 | 38.8 ± 1.6 | 0.842 | ||
| Neonatal birth weight (grams) | 2805 ± 558 | 2963 ± 470 | 0.001* | ||