Background characteristics of the study population (n=91) with tidal flow–volume loop measurements in both the awake and sleeping arousal state
| Birth characteristics | |
| Girls (n=91) | 51 (56.0) |
| Gestational age at birth (weeks) (n=91) | 40.0±1.3 |
| Birth weight (kg) (n=91) | 3.5±0.5 |
| Birth length (cm) (n=82) | 50.3±2.0 |
| Infants at 3-month investigation | |
| Age (days) (n=91) | 91.0±7.3 |
| Weight (kg) (n=91) | 6.1±0.8 |
| Length (cm) (n=89) | 61.5±2.3 |
| Parents | |
| Mother's age (years) (n=91) | 32.7±3.6 |
| Nordic origin of mothers# (n=87) | 82 (94.3) |
| Asthma reported in mother (n=87) | 19 (21.8) |
| Asthma reported in father (n=85) | 8 (9.4) |
Data are presented as n (%) or mean±sd. #: based on maternal country of origin.