Description of covariates in terms of mode of delivery
| Vaginal delivery | Emergency caesarean | Elective caesarean | p Value | |
|---|---|---|---|---|
| (N=7156) | (N=106) | (N=85) | χ2 | |
| Variable | n (%) | n (%) | n (%) | |
| Cohort member's gender | 0.156 | |||
| Male | 3580 (50.0) | 61 (57.6) | 48 (56.5) | |
| Female | 3576 (50.0) | 45 (42.4) | 37 (43.5) | |
| Maternal age, years | <0.001 F | |||
| <18 | 69 (1.0) | 0 (0.0) | 0 (0.0) | |
| 18–35 | 6414 (89.7) | 87 (82.1) | 63 (74.1) | |
| >35 | 668 (9.3) | 19 (17.9) | 22 (25.9) | |
| Mother's educational level | 0.045 | |||
| Low | 5224 (73.2) | 69 (65.7) | 54 (64.3) | |
| High | 1913 (26.8) | 36 (34.2) | 30 (35.7) | |
| Overcrowding | 0.049 | |||
| 1–1.5 people/room | 6140 (88.1) | 96 (96.0) | 73 (89.0) | |
| ≥1.5 people/room | 832 (11.9) | 4 (4.0) | 9 (11.0) | |
| Smoking after the fourth month of pregnancy | 0.589 | |||
| No | 4766 (67.4) | 74 (71.8) | 55 (65.5) | |
| Yes | 2303 (32.6) | 29 (28.2) | 29 (34.5) | |
| Maternal BMI before pregnancy | 0.075 F | |||
| Underweight | 305 (4.5) | 3 (3.1) | 4 (5.3) | |
| Normal weight | 4915 (72.6) | 69 (71.1) | 48 (63.2) | |
| Overweight | 1293 (19.1) | 18 (18.6) | 16 (21.0) | |
| Obesity | 262 (3.8) | 7 (7.2) | 8 (10.5) | |
| Parity | <0.001 | |||
| Nulliparous | 2636 (36.9) | 67 (63.2) | 20 (23.5) | |
| 1 previous pregnancy | 2269 (31.7) | 20 (18.9) | 32 (37.7) | |
| ≥2 previous pregnancies | 2250 (31.4) | 19 (17.9) | 33 (38.8) | |
| Problems with previous pregnancies | <0.001 | |||
| No | 5638 (78.9) | 73 (68.9) | 36 (42.4) | |
| Yes | 1504 (21.1) | 33 (31.1) | 49 (57.6) | |
| Hypertensive pathology during pregnancy | 0.002 | |||
| No | 4654 (68.3) | 59 (62.1) | 41 (51.3) | |
| Yes | 2164 (31.7) | 36 (37.9) | 39 (48.7) | |
| Abnormality during pregnancy | <0.001 | |||
| No | 5358 (74.9) | 50 (47.2) | 23 (27.1) | |
| Yes | 1794 (25.1) | 56 (52.8) | 62 (72.9) | |
| Total number of antenatal visits | 0.240 F | |||
| <5 | 295 (4.2) | 2 (1.9) | 4 (4.8) | |
| 5–9 visits | 1912 (27.1) | 25 (24.3) | 30 (36.1) | |
| >9 | 4859 (68.7) | 76 (73.8) | 49 (59.2) | |
| Birthweight | 0.392 | |||
| <10th centile | 525 (8.4) | 4 (4.8) | 6 (8.5) | |
| 10–90th centile | 5094 (81.7) | 67 (79.8) | 59 (83.1) | |
| >90th centile | 619 (9.9) | 13 (15.4) | 6 (8.4) | |
| Gestational age, weeks | <0.001 | |||
| <38 | 770 (9.8) | 14 (12.1) | 25 (25.5) | |
| 38 | 610 (7.8) | 15 (12.9) | 23 (23.5) | |
| 39–41 | 5504 (70.4) | 59 (50.9) | 45 (45.9) | |
| >41 | 935 (12.0) | 28 (24.1) | 5 (5.1) | |
| Whether labour induced | <0.001 | |||
| No | 6242 (87.2) | 68 (64.2) | 81 (95.3) | |
| Yes | 914 (12.8) | 38 (35.8) | 4 (4.7) | |
| PROM >12h | <0.001 | |||
| No | 5599 (85.0) | 55 (55.6) | 83 (100.0) | |
| Yes | 985 (15.0) | 44 (44.4) | 0 (0.0) |
Per cent may not add up exactly to 100 due to rounding.
BMI, body mass index; F, Fisher's exact test; PROM, premature rupture of the membranes.