Birth characteristics | OR | 95% CI | |
---|---|---|---|
Father’s social classa | |||
 No father in household/Other | 2.20*** | 1.48 | 3.28 |
 Manual | 2.02*** | 1.61 | 2.54 |
 Non-manual (reference) | 1 |  |  |
Mother smoked during pregnancyb | |||
 No (reference) | 1 |  |  |
 Stopped prior or during the pregnancy | 0.77 | 0.50 | 1.18 |
 Smoked during pregnancy | 1.24* | 1.03 | 1.49 |
Maternal age at birthc | |||
 19 or less years | 1.25 | 0.90 | 1.74 |
 20–34 years (reference) | 1 |  |  |
 35 or more years | 1.13 | 0.85 | 1.48 |
Birthweight standardized for gestationd | |||
 1st quarter (lowest) | 1.01 | 0.78 | 1.30 |
 2nd quarter | 0.91 | 0.70 | 1.18 |
 3rd quarter (reference) | 1 |  |  |
 4th quarter (highest) | 1.05 | 0.80 | 1.39 |
Breastfede | |||
 Less than 1 month | 1.30* | 1.05 | 1.60 |
 1 or more months (reference) | 1 |  |  |