Table 3.
Adverse perinatal outcomes (‘intrapartum composite’) for babies of ‘higher risk’ women by parity and planned place of birth
| Events | Births | Weighted* | Unadjusted* | Adjusted** | ||||
|---|---|---|---|---|---|---|---|---|
| n | n | n/1000 | 95% CI | RR | 95% CI | RR | 95% CI | |
| All ‘higher risk’ women (‘population 1’) | ||||||||
| Overall (Wald test for interaction P = 0.88***) | ||||||||
| OU | 29 | 6648 | 4.2 | 2.9–6.1 | 1 | – | ||
| Home | 12 | 1471 | 7.1 | 4.1–12.2 | 1.68 | 0.87–3.25 | 1.92 | 0.97–3.80 |
| Nulliparous | ||||||||
| OU | 15 | 2508 | 6.0 | 3.7–9.7 | 1 | – | ||
| Home | 4 | 284 | 10.6 | 4.2–26.8 | 1.77 | 0.62–5.05 | ||
| Parous | ||||||||
| OU | 14 | 4140 | 3.1 | 1.8–5.5 | 1 | – | ||
| Home | 8 | 1187 | 6.2 | 3.0–12.9 | 1.99 | 0.79–5.00 | ||
| ‘Higher risk’ women without ‘complicating conditions’ (‘population 2’) | ||||||||
| Overall (Wald test for interaction P = 0.53***) | ||||||||
| OU | 18 | 4715 | 3.8 | 2.6–5.6 | 1 | – | ||
| Home | 10 | 1312 | 6.7 | 3.6–12.4 | 1.75 | 0.84–3.62 | 2.05 | 0.98–4.29 |
| Nulliparous | ||||||||
| OU | 10 | 1528 | 6.5 | 3.7–11.5 | 1 | – | ||
| Home | 3 | 249 | 9.2 | 3.0–27.6 | 1.41 | 0.41–4.87 | ||
| Parous | ||||||||
| OU | 8 | 3187 | 2.5 | 1.3–4.8 | 1 | – | ||
| Home | 7 | 1063 | 6.1 | 2.8–13.4 | 2.43 | 0.88–6.71 | ||
*
Probability weights are incorporated to account for differences in the probability of a woman being selected for inclusion in the study arising from differences in each unit/trust's period of participation and the stratum-specific probabilities of selection of OUs.
**
Adjusted for parity.
***
P-value for interaction between parity and planned place of birth.