Table 2.
Labor characteristic of the participant pregnant women by ABO blood groups.
| O (n = 666, 39.7%) | A (n = 508, 30.3%) | B (n = 395, 23.5%) | AB (n = 109, 6.5%) | F/Z/χ2 value | p value | |
|---|---|---|---|---|---|---|
| Gestational age at delivery (week), mean ± SD | 37.16 ± 2.47 | 36.86 ± 2.61 | 37.25 ± 2.41 | 36.46 ± 2.83 | 4.092 | 0.007 |
| Preterm birth (<37 week) | 270 (41.3%) | 225 (45.4%) | 142 (36.5%) | 54 (50.5%) | 10.389 | 0.015 |
| Emergency admission | 595 (89.3%) | 442 (87.0%) | 355 (89.9%) | 97 (89.0%) | 2.279 | 0.518 |
| Cesarean delivery | 510 (76.6%) | 401 (78.9%) | 277 (70.1%) | 87 (79.8%) | 10.859 | 0.012 |
| Estimated blood loss (mL), median (IQR) | 600 (400-1300) | 600 (400-1200) | 500 (350-1000) | 500 (385-1000) | 4.174 | 0.243 |
| Postpartum hemorrhage | 165 (24.8%) | 123 (24.2%) | 80 (20.3%) | 23 (21.1%) | 3.394 | 0.335 |
| Cesarean hysterectomy | 7 (1.1%) | 8 (1.6%) | 1 (0.3%) | 3 (2.8%) | 6.527 | 0.067 |
| Transfusion of blood products | 230 (34.5%) | 173 (34.1%) | 113 (28.6%) | 37 (33.9%) | 4.457 | 0.217 |
| Postdelivery hemoglobin (g/L) | 102.78 ± 15.42 | 100.95 ± 16.54 | 102.55 ± 14.93 | 101.24 ± 13.04 | 1.332 | 0.262 |
| Postdelivery anemia (hemoglobin < 110 g/L) | 390 (70.3%) | 310 (71.8%) | 211 (67.4%) | 73 (75.3%) | 2.828 | 0.420 |
| Placental length (cm) | 19.20 ± 2.20 | 19.17 ± 2.29 | 19.34 ± 2.59 | 19.03 ± 2.42 | 0.685 | 0.561 |
| Placental width (cm) | 18.65 ± 2.05 | 18.74 ± 2.21 | 18.73 ± 2.46 | 18.53 ± 2.35 | 0.388 | 0.762 |
| Placental depth (cm) | 2.21 ± 0.42 | 2.24 ± 0.44 | 2.21 ± 0.38 | 2.18 ± 0.40 | 0.761 | 0.516 |
| Placental surface area (cm2) | 283.65 ± 62.93 | 288.12 ± 82.47 | 288.49 ± 77.70 | 280.52 ± 71.88 | 0.713 | 0.544 |
| Placental volume (cm3) | 436.62 ± 306.50 | 456.01 ± 395.09 | 4458.42 ± 380.20 | 412.99 ± 160.84 | 0.788 | 0.500 |
| Placental weight (g) | 580.71 ± 178.59 | 585.75 ± 198.21 | 582.41 ± 134.38 | 576.11 ± 139.53 | 0.091 | 0.965 |
| Male newborn | 378 (56.8%) | 313 (61.6%) | 213 (53.9%) | 71 (65.1%) | 8.118 | 0.044 |
| Neonatal asphyxia | 61 (9.2%) | 35 (6.9%) | 16 (4.1%) | 9 (8.3%) | 9.931 | 0.019 |
| Admission to the neonatal intensive care unit | 161 (24.2%) | 112 (22.0%) | 77 (19.5%) | 24 (22.0%) | 3.170 | 0.367 |
| Apgar score of <7 at 1 min | 53 (8.0%) | 33 (6.5%) | 16 (4.1%) | 9 (8.3%) | 6.637 | 0.083 |
| Apgar score of <7 at 5 min | 5 (0.8%) | 6 (1.2%) | 3 (0.8%) | 0 (0) | 1.082 | 0.779 |
| Apgar score of <7 at 10 min | 1 (0.2%) | 3 (0.6%) | 1 (0.3%) | 0 (0) | 1.885 | 0.611 |