Table 4 Associations with infant birthweight
|  | ≥2500 g No. (%) | < 2500g No. (%) | OR (95% CI) |
|---|---|---|---|
Maternal age | Â | Â | Â |
≤24 years | 3467 (95.8) | 151 (4.2) | 1.00 ref |
> 24 years | 376 (95.4) | 18 (4.6) | 1.10 (0.7-1.8) |
Adjusted household income (AUD) | Â | Â | Â |
< $20,000 | 830 (95.7) | 37 (4.3) | 1.00 (0.7-1.5) |
$20,000-$40,000 | 1799 (95.7) | 81 (4.3) | 1.00 ref |
> $40,000 | 904 (95.9) | 39 (4.1) | 1.00 (0.6-1.4) |
Educational attainment | Â | Â | Â |
Completed year 12 | 3147 (96.1) | 127 (3.9) | 1.00 ref |
Did not complete year 12 | 789 (94.0) | 50 (6.0) | 1.57 (1.1-2.2) |
Relationship status | Â | Â | Â |
Married | 3035 (95.7) | 135 (4.3) | 1.00 ref |
Living with partner | 766 (96.0) | 32 (4.0) | 0.93 (0.6-1.4) |
Single/divorced/separated | 160 (93.0) | 12 (7.0) | 1.69 (0.9-3.1) |
Maternal Country of birth | Â | Â | Â |
Australia | 3230 (96.1) | 130 (3.9) | 1.00 ref |
Overseas - English speaking | 241 (93.8) | 16 (6.2) | 1.65 (1.0-2.8) |
Overseas - Non-English speaking | 457 (93.5) | 32 (6.5) | 1.73 (1.2-2.6) |
Risk of complications in pregnancy | Â | Â | Â |
Lower risk | 2473 (98.1) | 49 (1.9) | 1.00 ref |
Higher risk | 1500 (92.0) | 130 (8.0) | 4.37 (3.1-6.1) |
Maternal pre-pregnant BMI | Â | Â | Â |
Underweight (< 18.5) | 163 (92.6) | 13 (7.4) | 1.74 (1.0-3.2) |
Normal weight (18.5-24.9) | 2193 (95.6) | 100 (4.7) | 1.00 ref |
Overweight (25.0-29.9) | 837 (96.0) | 35 (4.0) | 0.92 (0.6-1.4) |
Obese (≥30) | 537 (96.4) | 20 (3.6) | 0.82 (0.5-1.3) |
Smoking in pregnancy | Â | Â | Â |
Non-smoker | 3222 (96.1) | 132 (3.9) | 1. 00 ref |
Quit in pregnancy | 325 (96.0) | 13 (3.9) | 0.98 (0.5-1.7) |
Smoking throughout pregnancy | 343 (92.4) | 28 (7.6) | 1.99 (1.3-3.0) |
Stressful life events/social health issues | Â | Â | Â |
None | 1332 (96.8) | 44 (3.2) | 1.00 ref |
One to two issues | 1954 (95.7) | 88 (4.3) | 1.36 (1.0-2.0) |
≥3 issues | 676 (93.6) | 46 (6.4) | 2.06 (1.3-3.1) |