Table 3 Association between parity and serum 25(OH)D concentration (multiple linear regression)
Parameters | 25(OH)D | ||
|---|---|---|---|
Mean ± standard | B (95%CI) | P value | |
Parity | |||
 0 | 59.2 ± 12.6 | -2.841 (-5.443, -0.240) | 0.032 |
 1 | 58.7 ± 12.4 | -3.439 (-6.066, -0.813) | 0.010 |
  ≥ 2 | 62.2 ± 13.1 | 1 (reference) |  |
Season at sampling | |||
 Spring | 53.7 ± 11.2 | -3.123 (-5.195, -1.052) | 0.003 |
 Summer | 60.3 ± 12.3 | 3.485 (1.424, 5.545) | 0.001 |
 Autumn | 69.8 ± 8.8 | 13.055 (10.742, 15.368) |  < 0.001 |
 Winter | 56.8 ± 11.4 | 1 (reference) |  |
Gestational weeks at sampling | |||
 11 | 59.5 ± 13.8 | 1.175 (-1.213, 3.563) | 0.335 |
  12 | 59.2 ± 12.6 | 0.993 (-0.881, 2.868) | 0.299 |
 13 | 58.9 ± 12.1 | 0.499 (-1.551, 2.548) | 0.633 |
 14 | 59.0 ± 12.4 | 1 (reference) |  |