| Final model | Stratified model | |
---|---|---|---|
aRR (95% CI) | East coast aRR (95% CI) | West coast aRR (95% CI) | |
Model I | |||
 Women’s age | – | – | 1.12 (1.01–1.24) |
 Middle income | – | – | 5.07 (1.65–15.59) |
 Low income | 2.18 (1.02–4.67) | – | 5.01 (1.25–20.15) |
 Primipara | 2.46 (1.62–3.71) | 2.00 (1.23–3.54) | 5.17 (2.29–11.72) |
 Underweight | 3.82 (2.07–7.03) | 4.69 (2.24–9.79) | 6.12 (1.69–28.05) |
 Physical abuse ever | 2.41 (1.22–4.74) | – | 7.18 (2.00–18.64) |
 Antepartum depressive symptoms | 3.58 (2.16–5.94) | 3.64 (1.79–7.40) | 3.82 (1.86–7.84) |
Model II | |||
 Women’s age | – | – | 1.12 (1.01–1.24) |
 Middle income | – | – | 4.61 (1.57–13.56) |
 Low income | 2.48 (1.18–5.20) | – | 5.82 (1.61–21.09) |
 Primipara | 2.35 (1.55–3.56) | – | 5.75 (2.59–12.77) |
 Underweight | 5.48 (3.03–9.78) | 7.92 (4.17–15.04) | 7.84 (2.71–22.66) |
 Physical abuse ever | 4.52 (2.36–8.66) | – | 14.76 (5.63–38.67) |
 Antepartum anxiety symptoms | – | 2.47 (1.39–4.38) | – |