Table 4.
Odds of SGA by census dissemination area average income with and without adjustment for maternal risk factors
| |
|
Model 1 |
Model 2 |
|---|---|---|---|
| Independent variables | n | OR (95% CI) | OR (95% CI) |
| Average income quintile |
|
|
|
| 1 ($6,196–$24,444) |
11444 |
Reference |
Reference |
| 2 ($24,444–$28,440) |
11510 |
0.9 (0.8, 1.0)* |
0.9 (0.8, 1.0) |
| 3 ($28,440–$32,954) |
11953 |
0.8 (0.7, 0.9)*** |
0.9 (0.8, 1.0) |
| 4 ($32,986–$38,832) |
12163 |
0.7 (0.6, 0.8)*** |
0.8 (0.7, 0.9)*** |
| 5 ($38,837–$509,269) |
11969 |
0.6 (0.5, 0.7)*** |
0.8 (0.7, 0.8)*** |
| Smoking during pregnancy |
|
|
|
| No |
55561 |
|
Reference |
| Yes |
3478 |
|
1.6 (1.4, 1.8)*** |
| Maternal age |
|
|
|
| <20 |
927 |
|
0.8 (0.6, 1.0)* |
| 20–35 |
42675 |
|
Reference |
| ≥ 35 |
15437 |
|
1.0 (0.9, 1.1) |
| Parity |
|
|
|
| 0 |
29296 |
|
Reference |
| ≥ 1 |
29543 |
|
0.5 (0.5, 0.6)*** |
| Pre-pregnancy BMI |
|
|
|
| Underweight (<18.5) |
4098 |
|
1.8 (1.6, 2.0)*** |
| Normal weight (18.5–25) |
37718 |
|
Reference |
| Overweight (25–30) |
11494 |
|
0.7 (0.7, 0.8)*** |
| Obese (≥30) |
5729 |
|
0.6 (0.5, 0.6)*** |
| Height (continuous, cm) |
59039 |
|
0.9 (0.9, 0.9)*** |
| Diabetes/ Hypertension |
|
|
|
| Neither |
50163 |
|
Reference |
| Diabetes only |
5615 |
|
0.9 (0.8, 1.0) |
| Hypertension only |
2653 |
|
2.4 (2.1, 2.7)*** |
| Diabetes & hypertension |
608 |
|
1.5 (1.1, 2.0)* |
| Oligohydramnios |
|
|
|
| No |
57656 |
|
Reference |
| Yes |
1383 |
|
3.9 (3.4, 4.4)*** |
| Placenta disorder |
|
|
|
| No |
57788 |
|
Reference |
| Yes | 1251 | 1.4 (1.2, 1.7)** |
* 2-sided p < 0.05; ** 2-sided p < 0.001; *** 2-sided p < 0.0001.