| P value | Odds Ratio | 95.0% C.I. | ||
| Maternal age | 0.893 | 0.990 | 0.850 | 1.153 |
| Cervical length | 0.026 | 2.273 | 1.102 | 4.688 |
| GA at TVS | 0.239 | 1.292 | 0.843 | 1.980 |
| GA at onset/inductin of labour | 0.796 | 0.958 | 0.690 | 1.330 |
| Mode of induction (induced) | 0.175 | 2.633 | 0.650 | 10.672 |
| Induction to delivery interval | 0.031 | 1.051 | 1.005 | 1.100 |