Table 3 OASIS according to classification of episiotomy practices, vaginal deliveries, 2011–2016
Classification of episiotomy practices | Number of OASIS / Number of women | OASIS rate of each group (%) | Relative size of each group (%)a | Contribution of each group to OASIS rate (%) b |
|---|---|---|---|---|
1 – Nulliparous women with a single cephalic pregnancy, at ≥37 weeks gestation, non-instrumental delivery | 243/ 22,239 | 1.1 | 27.4 | 33.9 |
2 – Nulliparous women with a single cephalic pregnancy at ≥37 weeks gestation, instrumental delivery | 271/ 8984 | 3.0 | 11.1 | 37.8 |
3 – Multiparous women with a single cephalic pregnancy at ≥37 weeks gestation, non- instrumental delivery | 122/ 41,929 | 0.3 | 51.6 | 17.0 |
4 – Multiparous women with a single cephalic pregnancy at ≥37 weeks gestation, instrumental delivery | 60/ 2677 | 2.2 | 3.3 | 8.4 |
5 – All women with a single cephalic pregnancy at < 37 weeks gestation | 12/ 3374 | 0.4 | 4.2 | 1.7 |
6 – All women with a single breech pregnancy | 5/ 1268 | 0.4 | 1.6 | 0.7 |
7 – All women with multiple pregnancy | 4/ 819 | 0.5 | 1.0 | 0.6 |
Total | 717/ 81,290 | 0.9 | 100 | 100 |