| Variables |
| Vaginal delivery (%) | Cesarean delivery (%) | χ2 | P |
| Allergic history | No | 1153 (66.5) | 581 (33.5) | 0.146 | 0.703 |
|
| Yes | 204 (65.4) | 108 (34.6) |
|
|
| History of cesarean section* | No | 1308 (77.9) | 370 (22.1) | 564.518 | <0.001 |
|
| Yes | 49 (13.3) | 319 (86.7) |
|
|
| History of infertility* | No | 1202 (68.2) | 560 (31.8) | 20.375 | <0.001 |
|
| Yes | 155 (54.6) | 129 (45.4) |
|
|
| History of adverse pregnancy or childbirth* | No | 1223 (67.7) | 583 (32.3) | 13.399 | <0.001 |
|
| Yes | 134 (55.8) | 106 (44.2) |
|
|
| Birth parity* | ≤2 | 950 (72.3) | 364 (27.7) | 58.682 | <0.001 |
|
| ＞2 | 407 (55.6) | 325 (44.4) |
|
|
| Hypertension* | No | 1351 (66.7) | 675 (33.3) | 11.932 | 0.001 |
|
| Yes | 6 (30.0) | 14 (70.0) |
|
|
| Diabetes | No | 1343 (66.5) | 676 (33.5) | 2.566 | 0.109 |
|
| Yes | 14 (51.9) | 13 (48.1) |
|
|
| Hyperlipidemia | No | 1330 (66.3) | 675 (33.7) | 0.004 | 0.949 |
|
| Yes | 27 (65.9) | 14 (34.1) |
|
|
| Ovarian cyst or Polycystic ovary syndrome | No | 1242 (66.5) | 626 (33.5) | 0.258 | 0.612 |
|
| Yes | 115 (64.6) | 63 (35.4) |
|
|
| Hypothyroidism | No | 1303 (66.4) | 659 (33.6) | 0.163 | 0.686 |
|
| Yes | 54 (64.3) | 30 (35.7) |
|
|
| Hyperthyroidism | No | 1335 (66.4) | 677 (33.6) | 0.041 | 0.840 |
|
| Yes | 22 (64.7) | 12 (35.3) |
|
|
| Depression | No | 1342 (66.2) | 684 (33.8) | 0.681 | 0.409 |
|
| Yes | 15 (75.0) | 5 (25.0) |
|
|
| Anxiety | No | 1327 (66.1) | 680 (33.9) | 2.000 | 0.157 |
|
| Yes | 30 (76.9) | 9 (23.1) |
|
|
| Hepatitis B * | No | 1274 (67.1) | 626 (32.9) | 6.320 | 0.012 |
|
| Yes | 83 (56.8) | 63 (43.2) |
|
|
| Thalassemia | No | 1234 (66.7) | 615 (33.3) | 1.475 | 0.225 |
|
| Yes | 123 (62.4) | 74 (37.6) |
|
|
| Gestational diabetes mellitus * | No | 1094 (69.9) | 471 (30.1) | 38.191 | <0.001 |
|
| Yes | 263 (54.7) | 218 (45.3) |
|
|
| Gestational hypertension * | No | 1336 (67.1) | 656 (32.9) | 18.692 | <0.001 |
|
| Yes | 21 (38.9) | 33 (61.1) |
|
|
| Preeclampsia * | No | 1351 (67.1) | 662 (32.9) | 34.806 | <0.001 |
|
| Yes | 6 (18.2) | 27 (81.8) |
|
|
| Threatened premature labor * | No | 1300 (67.0) | 640 (33.0) | 7.885 | 0.005 |
|
| Yes | 57 (53.8) | 49 (46.2) |
|
|
| Premature rupture of membranes * | No | 1177 (65.5) | 620 (34.5) | 4.516 | 0.034 |
|
| Yes | 180 (72.3) | 69 (27.7) |
|
|
| Fetal distress * | No | 1291 (67.8) | 613 (32.2) | 26.907 | <0.001 |
|
| Yes | 66 (46.5) | 76 (53.5) |
|
|
| Threatened miscarriage | No | 1331 (66.5) | 670 (33.5) | 1.505 | 0.220 |
|
| Yes | 26 (57.8) | 19 (42.2) |
|
|
| Pregnancy anemia | No | 1232 (66.5) | 622 (33.5) | 0.141 | 0.707 |
|
| Yes | 1125 (65.1) | 67 (34.9) |
|
|