Prenatal factors and early remission (<12 years of age) of childhood asthma analysed by logistic regression model in asthma patients (OR, 95% CI)
| Crude OR | 95% CI | Adjusted OR* | 95% CI | |
| Maternal age | 0.91 | 0.88 to 0.94 | 0.91 | 0.87 to 0.94 |
| Gestational age | 0.98 | 0.97 to 1.00 | 0.99 | 0.97 to 1.00 |
| Birth weight | 0.96 | 0.94 to 0.98 | 0.99 | 0.96 to 1.02 |
| Parity | ||||
| 1 | Ref | Ref | ||
| 2 | 1.05 | 0.99 to 1.12 | 1.12 | 1.04 to 1.19 |
| ≥3 | 1.03 | 0.95 to 1.11 | 1.11 | 1.01 to 1.21 |
| Maternal social status | ||||
| Not in labour market | 1.15 | 1.06 to 1.24 | 1.06 | 0.98 to 1.15 |
| Unskilled workers | 1.33 | 1.15 to 1.54 | 1.30 | 1.12 to 1.50 |
| Skilled workers and white-collar workers | 1.27 | 1.19 to 1.36 | 1.20 | 1.12 to 1.28 |
| Top level status | Ref | Ref | ||
| Residence | ||||
| Capital or capital suburb | 0.93 | 0.87 to 0.99 | 0.97 | 0.91 to 1.04 |
| Provincial city or town | 0.86 | 0.79 to 0.93 | 0.89 | 0.82 to 0.97 |
| Rural areas | Ref | Ref | ||
| Maternal smoking during pregnancy | 1.24 | 1.17 to 1.32 | 1.19 | 1.12 to 1.27 |
| Maternal history of asthma | 0.80 | 0.71 to 0.89 | 0.78 | 0.69 to 0.87 |
| Sex | ||||
| Male | Ref | Ref | ||
| Female | 1.20 | 1.13 to 1.27 | 1.20 | 1.13 to 1.27 |
| Mode of delivery | ||||
| Delivered vaginally | Ref | Ref | ||
| Delivered by caesarean section | 1.02 | 0.93 to 1.12 | 1.01 | 0.91 to 1.12 |
| Age of asthma onset | 1.48 | 1.47 to 1.50 | 1.48 | 1.46 to 1.50 |
*Logistic regression model (OR, 95% CI) adjusting for maternal age at delivery; maternal parity; maternal socio-economic status at delivery; maternal smoking status during pregnancy; maternal history of asthma; sex of the child; gestational weeks at delivery; maternal residence at delivery; birth weight, delivery method and age of asthma onset.