Table 1 Maternal demographics and labour characteristics
Variable | All N = 27,648 | Occiput posterior N = 1292 | Occiput anterior N = 26,356 | P value |
|---|---|---|---|---|
Maternal age (years) | ||||
Mean (SD) | 30.7 (5.0) | 30.6 (5.0) | 30.7 (5.0) | 0.53 |
≥ 35 | 5404 (19.5) | 251 (19.4) | 5153 (19.6) | 0.96 |
Nulliparity | 12,806 (46.3) | 750 (58.1) | 12,056 (45.7) | < 0.001 |
Missing | 6 (0.02) | 2 (0.15) | 4 (0.02) | |
Gestational length | ||||
Mean (SD), days | 280 ± 8 | 281 ± 9 | 280 ± 8 | 0.005 |
< 41 weeks | 19,836 (71.7) | 885 (68.5) | 18,951 (71.9) | 0.008 |
Normal pregnancy | 20,950 (85.2) | 925 (80.4) | 20,025 (85.5) | < 0.001 |
Missing | 3064 (11) | 141 (11) | 2923 (11) | |
Induction of labour | 4018 (14.6) | 247 (19.2) | 3771 (14.4) | < 0.001 |
Missing | 198 (0.7) | 7 (0.5) | 191 (0.7) | |
Oxytocin | ||||
In the first stage of labour | 7436 (26.9) | 599 (46.4) | 6837 (25.9) | < 0.001 |
In the second stage of labour | 7880 (28.5) | 483 (37.4) | 7397 (28.1) | < 0.001 |
First and second stage | 4255 (15.4) | 258 (20.0) | 3997 (15.2) | < 0.001 |
Epidural analgesia | 9276 (33.6) | 620 (48.0) | 8656 (32.8) | < 0.001 |
Duration of pushing (min) | ||||
Mean (SD) | 39.0 (113.8) | 51.4 (123.1) | 38.6 (113.5) | 0.003 |
> 45 min | 4947 (21.7) | 255 (35.1) | 4692 (21.2) | < 0.001 |
Missing | 4811 (17) | 565 (44) | 4246 (16) | |
Mode of delivery | ||||
Spontaneous vaginal | 23,323 (84.4) | 635 (49.1) | 22,688 (86.1) | < 0.001 |
Operative vaginal | 2400 (8.7) | 197 (15.2) | 2203 (8.4) | < 0.001 |
Caesarean section | 1924 (7.0) | 460 (35.6) | 1464 (5.6) | < 0.001 |
Missing | 1 | 0 | 1 | |
Birth weight (g) | ||||
Mean (SD) | 3620 (487.2) | 3645 (508.5) | 3619 (486.1) | 0.07 |
< 3295 | 6770 (25.3) | 316 (25.0) | 6454 (25.3) | 0.80 |
3295–3925 | 13,242 (49.4) | 603 (47.7) | 12,639 (49.5) | 0.24 |
> 3925 | 6794 (25.3) | 344 (27.2) | 6450 (25.3) | 0.11 |
Missing | 842 (3) | 29 (2) | 813 (3) | |