Hierarchical multinomial logistic regression
| Variable* | Model 1† | Model 2† | Model 3† | |||
| Moderate‡ (n=960) | High‡ (n=413) | Moderate‡(n=960) | High‡ (n=413) | Moderate‡ (n=960) | High‡ (n=413) | |
| Age category (years) | ||||||
| <25 | 1§ | 1 | 1 | 1 | 1 | 1 |
| 25–29 | 1.56 (1.00 to 2.45) | 1.69 (0.96 to 2.98) | 1.55 (0.98 to 2.44) | 1.71 (0.97 to 3.01) | 1.53 (0.96 to 2.44) | 1.69 (0.94 to 3.06) |
| 30–34 | 1.55 (0.96 to 2.50) | 2.31 (1.28 to 4.16) | 1.55 (0.96 to 2.51) | 2.33 (1.30 to 4.19) | 1.49 (0.91 to 2.45) | 2.27 (1.23 to 4.22) |
| ≥35 | 1.48 (0.85 to 2.56) | 1.96 (1.01 to 3.81) | 1.48 (0.85 to 2.57) | 2.00 (1.02 to 3.91) | 1.42 (0.80 to 2.51) | 1.98 (0.97 to 4.01) |
| Ethnicity | ||||||
| Caucasian | 1 | 1 | 1 | 1 | 1 | 1 |
| Non-Caucasian | 0.89 (0.43 to 1.86) | 0.24 (0.06 to 0.86) | 0.89 (0.43 to 1.86) | 0.23 (0.063 to 0.85) | 0.96 (0.46 to 2.11) | 0.23 (0.06 to 0.86) |
| Marital status | ||||||
| Single | 1 | 1 | 1 | 1 | 1 | 1 |
| Married/partner | 1.35 (0.87 to 2.11) | 1.31 (0.76 to 2.25) | 1.37 (0.88 to 2.14) | 1.32 (0.76 to 2.27) | 1.25 (0.79 to 1.98) | 1.06 (0.59 to 1.88) |
| Education | ||||||
| Schooling ≤12 years | 1 | 1 | 1 | 1 | 1 | 1 |
| Schooling >12 years | 1.73 (1.20 to 2.50) | 1.49 (0.96 to 2.30) | 1.65 (1.14 to 2.39) | 1.48 (0.95 to 2.30) | 1.55 (1.06 to 2.26) | 1.35 (0.85 to 2.14) |
| Employment status | ||||||
| Not working | 1 | 1 | 1 | 1 | 1 | 1 |
| Working | 1.44 (0.95 to 2.18) | 0.78 (0.49 to 1.26) | 1.48 (0.98 to 2.26) | 0.78 (0.48 to 1.25) | 1.40 (0.92 to 2.14) | 0.66 (0.40 to 1.08) |
| Accommodation | ||||||
| Other | 1 | 1 | 1 | 1 | 1 | 1 |
| Own house | 1.02 (0.75 to 1.40) | 1.06 (0.73 to 1.53) | 1.02 (0.75 to 1.40) | 1.05 (0.73 to 1.53) | 0.99 (0.71 to 1.37) | 1.01 (0.68 to 1.48) |
| Socioeconomic | ||||||
| <24 | 1 | 1 | 1 | 1 | 1 | 1 |
| ≥24 | 1.40 (1.01 to 1.93) | 1.38 (0.93 to 2.03) | 1.44 (1.04 to 2.01) | 1.36 (0.92 to 2.01) | 1.46 (1.05 to 2.05) | 1.47 (0.98 to 2.21) |
| Maternity service¶ | ||||||
| Private | 1 | 1 | 1 | 1 | 1 | 1 |
| Public | 0.82 (0.60 to 1.12) | 0.90 (0.63 to 1.30) | 0.80 (0.58 to 1.10) | 0.91 (0.63 to 1.30) | 0.80 (0.58 to 1.10) | 0.93 (0.64 to 1.36) |
| BMI category** | ||||||
| Underweight/Normal | – | – | 1 | 1 | 1 | 1 |
| Overweight | 1.09 (0.83 to 1.44) | 0.97 (0.71 to 1.35) | 1.23 (0.85 to 1.50) | 1.04 (0.74 to 1.45) | ||
| Obese | 1.45 (0.98 to 2.15) | 0.91 (0.56 to 1.46) | 1.49 (1.00 to 2.22) | 0.96 (0.59 to 1.57) | ||
| Gravidity¶ | ||||||
| 1 Pregnancy | – | – | 1 | 1 | 1 | 1 |
| >1 Pregnancy | 0.79 (0.57 to 1.10) | 0.88 (0.56 to 1.46) | 0.87 (0.62 to 1.22) | 1.06 (0.71 to 1.58) | ||
| Smoking | ||||||
| Smokers | – | – | – | – | 1 | 1 |
| Non-smokers | 1.34 (1.00 to 1.80) | 1.45 (1.02 to 2.07) | ||||
| Alcohol | ||||||
| Drinkers | – | – | – | – | 1 | 1 |
| Non-drinkers | 0.62 (0.45 to 0.84) | 0.75 (0.52 to 1.08) | ||||
| Folic acid¶ | ||||||
| No | – | – | – | – | 1 | 1 |
| Yes | 1.06 (0.78 to 1.46) | 1.17 (0.80 to 1.70) | ||||
| Five a day¶ | ||||||
| No | – | – | – | – | 1 | 1 |
| Yes | 1.41 (0.94 to 2.11) | 1.90 (1.22 to 2.96) | ||||
| Fish¶ | ||||||
| No | -– | – | – | – | 1 | 1 |
| Yes | 1.35 (1.03 to 1.79) | 1.47 (1.07 to 2.03) | ||||
| Anxiety Index | – | – | – | – | 1.01 (1.00 to 1.01) | 1.00 (1.01 to 1.01) |
| Stress | – | – | – | – | 1.02 (1.01 to 1.05) | 1.01 (0.96 to 1.04) |
| Depression Scale | – | – | – | – | 1.01 (1.00 to 1.04) | 1.00 (1.01 to 1.06) |
| Limiting | – | – | – | – | 1.03 (1.00 to 1.01) | 0.85 (0.81 to 0.88) |
| All or nothing | – | – | -– | – | 1.02 (1.01 to 1.05) | 1.04 (1.01 to 1.08) |
Includes only variables collected at 15±1 weeks’ gestation (mode of delivery excluded).
*Reference category for predictors were used to take a more positive approach by focusing on factors that improve chances of moderate or high physical activity.
†RRR (95%, CI) P.
‡Reference category: low physical activity level.
¶Missing values.
§1 denotes reference category.
**Body mass index (BMI) category was defined based on the WHO guidelines as underweight (<18.5 kg/m2), normal weight (18.5–24.9 kg/m2), overweight (≥25–29.9 kg/m2) and obese (≥30 kg/m2)—underweight and normal were collapsed together for this analysis.