Maternal characteristics by planned place of birth
| Characteristics | Freestanding n=494 N (%) | Tertiary n=3157 N (%) | p Value* |
|---|---|---|---|
| Mean age | 29.6 | 28.5† | <0.001 |
| Median (mean) parity | 1 (0.9) | 1 (1.0) | 0.8 |
| Proportion of nulliparae | 208 (42.1) | 1364 (43.2) | 0.6 |
| Ethnicity | |||
| African | 5 (1.0) | 40 (1.3) | <0.001 |
| Asian | 100 (20.2) | 140 (4.4) | |
| European | 27 (5.5) | 92 (2.9) | |
| Oceania | 350 (70.9) | 2856 (90.5) | |
| Aboriginal/Torres Strait Islander | 12 (3.4)‡ | 165 (5.8)‡ | |
| South American | 4 (0.8) | 5 (0.2) | |
| North American | 7 (1.4) | 20 (0.6) | |
| Missing data | 1 (0.2) | 4 (0.1) | |
| Smoking status | |||
| Smoker | 27 (5.5) | 546 (17.3) | <0.001 |
| Risk at booking | |||
| Category B/C or C | 27 (5.5) | 0 | § |
| Risk at onset of labour | |||
| Category B/C or C | 65 (13.2) | 598 (18.9) | 0.002 |
| Previous caesarean section | 2 (0.4) | 430 (13.6) | <0.0001 |
*Statistically significant results in bold.
†From n=3156 women. Missing data from one woman.
‡Expressed as a percentage of the Oceania population in the corresponding cohort.
§Numbers too small, multivariate model cannot converge.