Robson group | 2000–2002 | 2003–2005 | 2006–2008 | 2009–2011 | 2000–2011 | p -value |
---|---|---|---|---|---|---|
1. Nullipara, single, cephalic, birth weight ≥ 2.5 kg, spontaneous labour | 70 (1094/15,688) | 55 (584/10,607) | 61 (533/8687) | 55 (410/7430) | 62 (2621/42,412) | < 0.001 |
2. Nullipara, single, cephalic, birth weight ≥ 2.5 kg, induced labour or elective CS | 110 (26/236) | 153 (23/150) | 119 (8/67) | 31 (10/320) | 87 (67/773) | < 0.001 |
3. Multipara, no previous CS, single, cephalic, birth weight ≥ 2.5 kg, spontaneous labour | 55 (976/17,679) | 50 (713/14,229 | 52 (556/10,749) | 59 (592/10,098) | 54 (2837/52,755) | 0.381 |
4. Multipara, no previous CS, single, cephalic, birth weight ≥ 2.5 kg, induced labour or elective CS | 86 (13/152) | 99 (10/101) | 23 (1/43) | 46 (24/518) | 59 (48/814) | 0.023 |
5. Previous CS, single, cephalic, birth weight ≥ 2.5 kg | 43 (126/2948) | 27 (68/2561) | 36 (86/2404) | 29 (121/4182) | 33 (401/12,095) | 0.014 |
6. Nullipara, single, breech | 299 (140/469) | 207 (43/208) | 185 (33/178) | 165 (30/182) | 237 (246/1037) | < 0.001 |
7. Multipara, single, breech | 307 (183/597) | 246 (87/354) | 241 (57/237) | 243 (69/284) | 269 (396/1472) | 0.024 |
8. Multiple pregnancies | 158 (258/1638) | 132 (163/1237) | 109 (119/1094) | 96 (114/1189) | 127 (654/5158) | < 0.001 |
9. Single, transverse or oblique lie | 238 (67/282) | 191 (33/173) | 167 (1/6) | 176 (12/68) | 214 (113/529) | 0.197 |
10. Single, cephalic, birth weight < 2.5 kg | 334 (2347/7033) | 316 (1504/4760) | 323 (1345/4170) | 302 (1234/4086) | 321 (6430/20,049) | 0.002 |
Total | 112 (5230/46,722) | 94 (3228/34,380) | 99 (2739/27,635) | 92 (2616/28,357) | 101 (13,813/137,094) | < 0.001 |