Breastfeeding practices and demographic characteristics
| Characteristic | At baseline | 12 years follow-up# | 18 years follow-up¶ | ||
| p-value | p-value | ||||
| Exclusive breastfeeding | |||||
| ≤17 weeks | 373 (60.5) | 209 (57.3) | 231 (56.2) | ||
| 18–<26 weeks | 225 (36.5) | 149 (40.8) | 172 (41.8) | ||
| ≥27 weeks | 16 (2.6) | 7 (1.9) | 8 (1.9) | ||
| Median (IQR) weeks | 14 (2–20) | 15 (2–21) | 0.03 | 15 (2–21) | 0.02 |
| Total breastfeeding | |||||
| ≤17 weeks | 154 (24.8) | 80 (21.9) | 88 (21.4) | ||
| 18–<26 weeks | 42 (6.8) | 18 (4.9) | 24 (5.8) | ||
| 27–<52 weeks | 196 (31.6) | 126 (34.5) | 132 (32.1) | ||
| ≥53 weeks | 209 (33.7) | 141 (38.6) | 167 (40.6) | ||
| Median (IQR) weeks | 43 (16–60) | 48 (20–64) | <0.01 | 46 (20–64) | <0.01 |
| Sex | |||||
| Male | 317 (51.1) | 189 (47.2) | 0.66 | 207 (50.5) | 0.69 |
| Maternal asthma | |||||
| Yes | 269 (43.3) | 157 (43.1) | 0.96 | 169 (41.3) | 0.19 |
| Maternal atopy | |||||
| Yes | 349 (68.5) | 243 (69.2) | 0.63 | 250 (69.8) | 0.34 |
| Maternal age (IQR) years | 31 (29–34) | 32 (29–35) | <0.01 | 32 (29–34) | <0.01 |
| Paternal age (IQR) years | 33 (30–36) | 34 (31–37) | <0.01 | 33 (31–37) | 0.02 |
Data are presented as n (%), unless otherwise stated. IQR: interquartile range. Missing data: period of exclusive breastfeeding n=4; period of total breastfeeding n=20. The given p-values are for the group followed up compared with the group who did not attend the follow-up. #: 59% of the original sample; ¶: 66% of the original sample.