Robson group | 2000–2002 | 2009–2011 | |
---|---|---|---|
OR | Crude OR (95% CI) | Adjusted OR (95% CI) | |
1. Nullipara, single, cephalic, birth weight ≥ 2.5 kg, spontaneous labour | 1 | 3.9 (3.6–4.1) | 2.4 (2.2–2.6)a |
2. Nullipara, single, cephalic, birth weight ≥ 2.5 kg, induced labour or elective CS | 1 | 17 (11–26) | 12 (7.5–20)b |
3. Multipara, no previous CS, single, cephalic, birth weight ≥ 2.5 kg, spontaneous labour | 1 | 3.5 (3.3–3.7) | 2.6 (2.4–2.8)a |
4. Multipara, no previous CS, single, cephalic, birth weight ≥ 2.5 kg, induced labour or elective CS | 1 | 30 (19–48) | 30 (19–48)c |
5. Previous CS, single, cephalic, birth weight ≥ 2.5 kg | 1 | 6.9 (5.9–8.2) | 6.3 (5.1–7.8)d |
6. Nullipara, single, breech | 1 | 4.8 (3.3–6.9) | 2.6 (1.7–4.0)a |
7. Multipara, single, breech | 1 | 4.8 (3.5–6.5) | 4.1 (3.0–5.7)e |
8. Multiple pregnancies | 1 | 3.7 (3.1–4.3) | 3.1 (2.6–3.7)f |
9. Single, transverse or oblique lie | 1 | 1.4 (0.6–3.0) | 1.4 (0.6-3.0)c |
10. Single, cephalic, birth weight < 2.5 kg | 1 | 3.7 (3.4–4.1) | 2.7 (2.5–3.1)a |
Total | 1 | 4.0 (3.9–4.1) | 2.8 (2.7–2.9)a |