| Variables | OR | IC | p-value |
| Natural delivery |
|
|
|
| No | 0.945 | 0.599 - 1.490 | 0.806 |
| Yes | 1 |
|
|
| Artificial delivery |
|
|
|
| No | 1 |
|
|
| Yes | 1.133 | 0.618 - 2.078 | 0.686 |
| Assisted delivery |
|
|
|
| No | 1 |
|
|
| Yes | 0.784 | 0.447 - 1.374 | 0.395 |
| Uterine massage |
|
|
|
| No | 1 |
|
|
| Yes | 0.784 | 0.447 - 1.374 | 0.395 |
| Application of oxytocin |
|
|
|
| No |
|
|
|
| Yes | 0.778 | 0.422 - 1.436 | 0.422 |
| Delivery hemorrhage |
|
|
|
| No | 1 |
|
|
| Yes | 0.783 | 0.269 - 2.276 | 0.653 |
| Number of pregnancy |
|
|
|
| ≤3 | 2.402 | 0.846 - 6.826 | 0.100* |
| 4 - 6 | 2.004 | 0.686 - 5.853 | 0.204 |
| >6 | 1 |
|
|
| Parity |
|
|
|
| ≤2 | 2.291 | 0.530 - 9.909 | 0.267 |
| 3 - 5 | 1.591 | 0.357 - 7.083 | 0.542 |
| >5 | 1 |
|
|
| 1st quarter RPC |
|
|
|
| Quarter 1 | 1.307 | 0.821 - 2.082 | 0.259 |
| Quarter 2 | 1.805 | 1.116 - 2.920 | 0.016* |
| 3rd trimester | 1 |
|
|
| Type of pregnancy |
|
|
|
| Twin pregnancy | 10.065 | 4.359 - 23.239 | 0.000* |
| Single pregnancy | 1 |
|
|
| Cesarean delivery |
|
|
|
| No | 1 |
|
|
| Yes | 1.366 | 0.706 - 2.644 | 0.355 |
| History of abortion |
|
|
|
| No | 1 |
|
|
| Yes | 1.520 | 1.034 - 2.234 | 0.033* |