Table 4.
Risk factors for different types of perineal trauma
| OASIS | Episiotomy | Sutured injury | Total perineal trauma | |||||
|---|---|---|---|---|---|---|---|---|
| Crude OR | Adjusted OR | Crude OR | Adjusted OR | Crude OR | Adjusted OR | Crude OR | Adjusted OR | |
| Primiparityd | 8.19 (3.21–20.89) | 9.90 (3.63–26.98)c | 15.92 (6.79–37.30) | 10.84 (4.28–27.45)c | 2.74 (2.25–3.33) | 3.07 (2.48–3.81)c | 3.25 (2.66–3.97) | 3.60 (2.89–4.49)c |
| Birthweight > 4000 g d | 1.93 (0.79–4.75) | 2.87 (1.07–7.75)a | 0.75 (0.31–1.85) | 1.58 (0.59–4.18) | 1.30 (1.10–1.54) | 1.48 (1.24–1.77)c | 1.32 (1.11–1.56) | 1.53 (1.28–1.83)c |
| Transfer before birth | 2.42 (0.71–8.30) | 0.46 (0.06–3.59) | 11.02 (5.31–22.84) | 3.98 (1.72–9.22)b | 1.33 (0.99–1.79) | 0.91 (0.65–1.28) | 1.60 (1.19–2.15) | 1.01 (0.71–1.42) |
| Country | 1.19 (0.70–2.03) | 1.07 (0.60–1.90) | 1.28 (0.82–2.01) | 1.27 (0.78–2.09) | 1.45 (1.32–1.58) | 1.42 (1.29–1.56)c | 1.47 (1.34–1.61) | 1.44 (1.31–1.59)c |
| Flexible sacrum positionse | 0.71 (0.29–1.75) | 0.68 (0.26–1.79) | 0.20 (0.10–0.44) | 0.20 (0.10-0.54)b | 0.89 (0.76–1.04) | 1.02 (0.86–1.21) | 0.84 (0.71–0.98) | 0.96 (0.81–1.14) |
| Waterbirth | 1.30 (0.54–3.16) | 0.99 (0.36–2.73) | 0.41 (0.16–1.06) | 0.36 (0.13–1.03) | 1.19 (1.02–1.39) | 1.01 (0.85–1.20) | 1.19 (1.02–1.39) | 1.01 (0.85–1.21) |
a < 0.05
b < 0.01
c < 0.001
dadjusted for birthweight, transfer, flexile sacrum positions, waterbirth, country
eadjusted for parity, birthweight, transfer, waterbirth