Table 3.
Baseline maternal characteristics—subsequent birth mode vaginal birth or caesarean section
| Characteristics, n, (%) | Vaginal birth | Caesarean section | p value |
|---|---|---|---|
| n = 105 (60.0) | n = 70 (40.0) | ||
| Maternal characteristics | |||
| Age at OASI birth, years, mean (SD) | 27.7 (4.7) | 28.0 (4.4) | 0.653 |
| Time between OASI birth and antenatal questionnaire completion, years, mean (SD) | 4.29 (3.39) | 3.94 (3.94) | 0.460 |
| Ethnicity | 0.260 | ||
| White | 47 (44.8) | 38 (54.3) | |
| Mixed/multiple | 1 (0.9) | 1 (1.4) | |
| Asian/Asian British | 35 (33.3) | 25 (35.7) | |
| Black/African/Caribbean/Black British | 17 (16.2) | 5 (7.2) | |
| Other/not known | 5 (4.8) | 1 (1.4) | |
| BMI, mean (SD) | 25.8 (5.3) | 27.8 (6.0) | 0.031 |
| Parity at recruitment | 0.469 | ||
| 1 | 73 (69.5) | 53 (75.7) | |
| 2 | 25 (23.8) | 15 (21.4) | |
| ≥3 | 7 (6.7) | 2 (2.9) | |
| Vaginal interval birth | 26 (24.8) | 3 (4.3) | <0.001 |
| OASI birth characteristics | |||
| OASI classification | 0.188 | ||
| 3A | 35 (33.3) | 15 (21.4) | |
| 3B | 32 (30.5) | 26 (37.1) | |
| 3C/4 | 11 (10.5) | 13 (18.6) | |
| Unspecified | 27 (25.7) | 16 (22.9) | |
| Method of repair | 0.433 | ||
| End-to-end | 46 (43.8) | 26 (37.1) | |
| Overlap | 28 (26.7) | 25 (35.7) | |
| Unspecified | 31 (29.5) | 19 (27.2) | |
| Mode of OASI birth | 0.131 | ||
| SVD | 69 (65.7) | 36 (51.4) | |
| Kiwi/ventouse | 11 (10.5) | 6 (8.6) | |
| Low/unspecified forceps | 21 (20.0) | 25 (35.7) | |
| Rotational forceps | 4 (3.8) | 3 (4.3) | |
| Neonatal characteristics for OASI birth | |||
| Gestational age, (weeks), median (IQR) | 40 (39, 40) | 40 (39,40) | 0.529 |
| Birth weight, (kg), mean (SD) | 3.404 (0.586) | 3.513 (0.606) | 0.237 |
| Head circumference (cm), mean (SD) | 33.8 (4.2) | 34.5 (1.7) | 0.214 |
| Subsequent birth characteristics | |||
| Maternal request for mode of birth | 91 (86.7) | 63 (90.0) | 0.506 |
| Bowel symptoms | 1 (0.9) | 19 (27.1) | <0.001 |
| Requested mode of study birth achieveda | 102 (97.1) | 63 (90.0) | 0.091 |
| Anal sphincter defect on antenatal EAUS | 3 (2.9) | 38 (54.3) | <0.001 |
IQR interquartile range, OASI obstetric anal sphincter injury, SVD spontaneous vaginal delivery
aExcludes the 5 women who were pursuing either a vaginal or caesarean section depending on clinical events