| |
N
|
Mean ± SD or n (%)
|
|---|
|
Maternal age (years)
|
715
|
30.8 ± 4.0
|
|
Maternal education level
|
714
| |
|
< 12 years
| |
84 (11.7)
|
|
12 years
| |
114 (16.0)
|
|
> 12 years
| |
516 (71.3)
|
|
Maternal prepregnancy body mass index
|
715
| |
|
≤ 25 kg/m2
| |
604 (84.5)
|
|
> 25 kg/m2
| |
111 (15.5)
|
|
Maternal tobacco consumption (early pregnancy)
|
710
| |
|
None
| |
547 (77.0)
|
|
< 10 cig/day
| |
118 (16.6)
|
|
≥ 10 cig/day
| |
45 (6.3)
|
|
Maternal occupational exposure to solvents
|
715
| |
|
No
| |
356 (49.8)
|
|
Occasional
| |
139 (19.4)
|
|
Regular
| |
220 (30.8)
|
|
Parity
|
715
| |
|
Nulliparous
| |
299 (41.8)
|
|
Parous
| |
416 (58.2)
|
|
Sex
|
715
| |
|
Boys
| |
379 (53.0)
|
|
Girls
| |
336 (47.0)
|
|
Breastfeeding
|
715
| |
|
None
| |
232 (32.4)
|
|
< 6 weeks
| |
331 (45.3)
|
|
≥ 6 weeks
| |
152 (21.3)
|
|
Mother-child interaction at age 2a
|
695
|
19.8 ± 3.5
|
- aScore varying between 5 and 25 (higher is better). For details, see Additional file 1: Table S2
