Table 1.
Characteristics of study sample
| Breastfeeding women (n = 124) | NPNB women (n = 124) | P value | ||
|---|---|---|---|---|
| Age (years) | Mean ± SD | 31.9 ± 5.0 | 31.8 ± 5.3 | 0.784‡ |
| Range | 20.0 − 44.0 | 19.0 − 45.0 | ||
| Height (m) | Mean ± SD | 1.68 ± 0.07 | 1.67 ± 0.07 | 0.663‡ |
| Range | 1.52 − 1.86 | 1.52 − 1.82 | ||
| Weight (kg) | Mean ± SD | 71.2 ± 14.5 | 68.4 ± 14.9 | 0.064‡ |
| Range | 48.0 − 142.0 | 43.0 − 120.0 | ||
| BMI (kg/m2) | Mean ± SD | 25.1 ± 4.8 | 24.3 ± 5.0 | 0.053‡ |
| Range | 18.2 − 46.4 | 17.0 − 40.8 | ||
| Season of blood sampling | ||||
| Spring | N (%) | 22 (17.7) | 22 (17.7) | 1.000* |
| Summer | 14 (11.3) | 14 (11.3) | ||
| Autumn | 63 (50.8) | 63 (50.8) | ||
| Winter | 25 (20.2) | 25 (20.2) | ||
| Skin type | ||||
| Light | N (%) | 109 (87.9) | 112 (90.3) | 0.292* |
| Dark | 15 (12.1) | 10 (8.1) | ||
| Recent holidays | N (%) | 5 (4.0) | 6 (4.8) | 0.758* |
| Smoking | N (%) | 11 (8.9) | 30 (24.2) | 0.001* |
| Duration of breastfeeding (month)a | Mean ± SD | 3.5 ± 3.2 | / | / |
| Range | 0.5 − 18.0 | |||
Autumn, September – November; BMI, body mass index; NPNB, non-pregnant and non-breastfeeding; SD, standard deviation; Spring, March – May; Summer, June – August; Winter, December – February
‡Mann-Whitney U-test
*Chi-square test
a n = 123