Table 2.
Definitive variables included in the postpartum hemorrhage risk calculator.
| NUMBER OF PARTICIPANTS BY CATEGORY | TOTAL N° in sub-categories | N° No Hemorrhage | % No Hemorrhage in sub-category | N° Hemorrhage | % Hemorrhage in sub-category | No Hemorrhage π1 | Hemorrhage π2 | |
|---|---|---|---|---|---|---|---|---|
| Weeks of gestation 1486 | Less than 35 weeks | 8 | 8 | 100% | 0 | 0% | 0.0075 | 0.0000 |
| Between 35 and 40 weeks | 280 | 179 | 63.92% | 101 | 36.07% | 0.1684 | 0.2388 | |
| More than 40 weeks | 1198 | 876 | 73.12% | 322 | 26.8% | 0.8241 | 0.7612 | |
| Hypertensive condition 1500 | No High blood pressure | 1444 | 1041 | 72.09% | 403 | 27.9% | 0.9693 | 0.9460 |
| Chronic hypertension | 10 | 7 | 70% | 3 | 30% | 0.0065 | 0.0070 | |
| Gestational hypertension | 46 | 26 | 56.52% | 20 | 43.4% | 0.0242 | 0.0469 | |
| Preeclamspsia 1500 | No | 1459 | 1053 | 72.17% | 406 | 27.8% | 0.9804 | 0.9531 |
| Mild | 24 | 14 | 58.33% | 10 | 41.6% | 0.0130 | 0.0235 | |
| Severe | 17 | 7 | 41.17% | 10 | 58.8% | 0.0065 | 0.0235 | |
| Pre-pregnancy abortion 1490 | No | 1068 | 772 | 72.2% | 296 | 27.7% | 0.7242 | 0.7064 |
| 1 previous abortion | 417 | 294 | 70.5% | 123 | 29.4% | 0.2758 | 0.2936 | |
| 2 or more previous abortions | 5 | 3 | 60% | 2 | 40% | 0.0028 | 0.0048 | |
| Parity 1495 | No previous deliveries | 821 | 600 | 73.08% | 221 | 26.9% | 0.5607 | 0.5200 |
| 1 previous delivery | 557 | 382 | 68.5% | 175 | 31.4% | 0.3570 | 0.4118 | |
| More than 1 previous delivery | 117 | 88 | 75.2% | 29 | 24.7% | 0.0822 | 0.0682 | |
| Previous cesarean section 1498 | No | 1333 | 958 | 71.86% | 375 | 28.1% | 0.8937 | 0.8803 |
| 1 previous cesarean section | 165 | 114 | 69.09% | 51 | 30.9% | 0.1063 | 0.1197 | |
| More than 1 previous cesarean | 0 | 0 | 0% | 0 | 0% | 0.0000 | 0.0000 | |
| Labor hours 1264 | Less than 1 h | 79 | 52 | 65.82% | 27 | 34.1% | 0.0579 | 0.0738 |
| More than 1 h and less than 5 h | 576 | 435 | 75.5% | 141 | 24.4% | 0.4844 | 0.3852 | |
| Between 5 and 10 h | 453 | 313 | 69.09% | 140 | 30.9% | 0.3486 | 0.3825 | |
| More than 10 h | 156 | 98 | 62.82% | 58 | 37.1% | 0.1091 | 0.1585 | |
| Placenta previa 349 | No | 340 | 192 | 56.47% | 148 | 43.5% | 0.9897 | 0.9548 |
| Yes | 9 | 2 | 22.22% | 7 | 77.7% | 0.0103 | 0.0452 | |
| History of postpartum hemorrhage 279 | No | 277 | 147 | 53.06% | 130 | 46.9% | 1.0000 | 0.9848 |
| Yes | 2 | 0 | 0% | 2 | 100% | 0.0000 | 0.0152 |
%: percentages in each variable subcategories for both patients without hemorrhage and those with PPH.
π1: probability assigned by the algorithm for no postpartum hemorrhage, π2: probability assigned by the algorithm for postpartum hemorrhage.