Characteristics according to degree of tear among primiparous women (n=554)
| Total (n=554) | Group 1 | Group 2 | Group 3 | |
| (No/labia/first degree) (n=191) | (Second degree) (n=189) | (Third/fourth degree) (n=174) | ||
| n (%) | n (%) | n (%) | n (%) | |
| BMI, pre-pregnancy (kg/m2)* | ||||
| <25 | 357 (64.6) | 128 (67.0) | 116 (61.7) | 113 (64.9) |
| 25–29.9 | 126 (22.8) | 41 (21.5) | 46 (24.5) | 39 (22.4) |
| ≥29.9 | 70 (12.7) | 22 (11.5) | 26 (13.8) | 22 (12.6) |
| Age at inclusion (years) | ||||
| ≤25 | 141 (25.5) | 63 (33.0) | 50 (26.5) | 28 (16.1) |
| 26–30 | 278 (50.2) | 91 (47.6) | 89 (47.1) | 98 (56.3) |
| >30 | 135 (24.4) | 37 (19.4) | 50 (26.5) | 48 (27.6) |
| Active birth duration (min) | ||||
| <220 | 140 (25.3) | 69 (36.1) | 46 (24.3) | 25 (14.4) |
| 221–340 | 141 (25.5) | 45 (23.6) | 53 (28.0) | 43 (24.7) |
| 341–570 | 143 (25.8) | 50 (26.2) | 49 (25.9) | 44 (25.3) |
| >570 | 130 (23.5) | 27 (14.1) | 41 (21.7) | 62 (35.6) |
| Second stage duration (min) | ||||
| <16 | 109 (19.7) | 40 (20.9) | 47 (24.9) | 22 (12.6) |
| 16–30 | 187 (33.8) | 80 (41.9) | 60 (31.8) | 47 (27.0) |
| 31–45 | 89 (16.1) | 31 (16.2) | 27 (14.3) | 31 (17.8) |
| >45 | 169 (30.5) | 40 (20.9) | 55 (29.1) | 74 (42.5) |
| Birth weight (g) | ||||
| <2999 | 76 (13.7) | 39 (20.4) | 23 (12.2) | 14 (8.1) |
| 3000–3499 | 193 (34.8) | 69 (36.1) | 81 (42.9) | 43 (24.7) |
| 3500–3999 | 210 (37.9) | 64 (33.5) | 65 (34.4) | 81 (46.6) |
| ≥4000 | 75 (13.5) | 19 (10.0) | 20 (10.6) | 36 (20.7) |
| Head circumference (cm)† | ||||
| <34 | 141 (25.5) | 58 (30.5) | 52 (27.7) | 31 (17.8) |
| 34 | 119 (21.6) | 45 (23.7) | 37 (19.7) | 37 (21.3) |
| 35 | 131 (23.7) | 35 (18.4) | 53 (28.2) | 43 (24.7) |
| >35 | 161 (29.2) | 52 (27.4) | 46 (24.5) | 63 (36.2) |
| Pre-pregnancy dyspareunia (yes) | 107 (19.3) | 26 (13.6) | 39 (20.6) | 42 (24.1) |
| Operative delivery (yes) | 95 (17.2) | 6 (3.1) | 29 (15.3) | 60 (34.5) |
| Episiotomies (yes) | 54 (9.8) | – | 32 (16.9) | 22 (12.6) |
| Smoker at inclusion (yes)* | 21 (3.8) | 8 (4.2) | 8 (4.2) | 5 (2.9) |
| Diabetes mellitus (yes) | 19 (3.4) | 5 (2.6) | 7 (3.7) | 7 (4.0) |
*One missing value, n=553.
†Two missing values, n=552.
BMI, body mass index.