No exacerbation | One exacerbation | Multiple exacerbations | |||||
Pregnancies | OR (95%CI) | aOR# (95%CI) | Pregnancies | OR (95%CI) | aOR# (95%CI) | ||
Subjects n | 32 399 | 1238 | 192 | ||||
Birthweight categories | |||||||
≤2499 g | 1180 (3.6) | 49 (4.0) | 1.14 (0.85–1.53) | 0.97 (0.69–1.35) | 11 (5.7) | 1.68 (0.90–3.12) | 1.43 (0.69–2.96) |
2500–2999 g | 3601 (11.1) | 191 (15.4) | 1.45 (1.24–1.70) | 1.39 (1.17–1.65) | 33 (17.2) | 1.65 (1.12–2.43) | 1.89 (1.24–2.86) |
3000–3999 g¶ | 21 595 (66.7) | 789 (63.8) | Ref. | Ref. | 120 (62.8) | Ref. | Ref. |
≥4000 g | 5965 (18.4) | 208 (16.8) | 0.95 (0.82–1.12) | 0.95 (0.80–1.13) | 27 (14.1) | 0.81 (0.54–1.24) | 0.85 (0.54–1.32) |
Missing | 58 (0.2) | 1 (0.1) | 1 (0.5) | ||||
Preterm birth | |||||||
Yes | 1834 (5.7) | 71 (5.7) | 1.01 (0.79–1.29) | 0.95 (0.73–1.24) | 14 (7.3) | 1.31 (0.77–2.25) | 1.38 (0.78–2.43) |
Missing | 13 (0.04) | 0 | 1 (0.5) | ||||
Small for gestational age | |||||||
Yes | 856 (2.6) | 40 (3.2) | 1.23 (0.89–1.70) | 1.11 (0.78–1.57) | 12 (6.3) | 2.48 (1.37–4.47) | 2.58 (1.38–4.82) |
Missing | 72 (0.2) | 1 (0.1) | 2 (1.0) | ||||
Mode of delivery | |||||||
Vaginal/ instrumental | 25 809 (79.7) | 913 (73.8) | Ref. | Ref. | 133 (69.3) | Ref. | Ref. |
Elective caesarean section | 2807 (8.7) | 138 (11.2) | 1.39 (1.16–1.67) | 1.37 (1.13–1.67) | 32 (16.7) | 2.21 (1.48–3.29) | 2.29 (1.52–3.46) |
Emergency caesarean section | 3387 (10.5) | 162 (13.1) | 1.35 (1.14–1.61) | 1.31 (1.10–1.58) | 25 (13.0) | 1.43 (0.93–2.20) | 1.37 (0.86–2.19) |
Unknown caesarean section | 396 (1.2) | 25 (2.0) | 2 (1.0) |
Data are presented as n (%), unless otherwise stated. #: adjusted for maternal smoking, obesity, education, country of birth, parity and depression/anxiety, and infant sex; ¶: approximately mean±1sd in population.