Table 1.
| Pregnant (n = 26) | Nonpregnant (n = 21) | P-value | |
|---|---|---|---|
| Age, y | 280 ± 3 | 29 ± 5 | 0.791 |
| Pre-pregnancy or baseline BMI, kg/m2 | 23.7 ± 3.1 | 23.5 ± 2.8 | 0.813 |
| Ethnicity, n | 0.716 | ||
| White/Non-White | 16/10 | 14/7 | |
| Multivitamin supplement uses before study entry, n | <0.001 | ||
| Yes/No | 22/4 | 7/14 | |
| CYP2R1 rs10741657 A>G polymorphism, n | 0.012 | ||
| AA/AG/GG, n | 2/20/4 | 2/8/11 | |
| CYP2R1 rs12794714 A>G polymorphism, n | 0.153 | ||
| AA/AG/GG | 1/20/5 | 4/11/6 | |
| GC rs7041 G>T polymorphism, n | 0.873 | ||
| GG/GT/TT | 9/11/6 | 6/9/6 | |
| Season at study entry, n | 0.920 | ||
| April–September/October–March | 14/12 | 11/10 | |
| Serum 25(OH)D, nmol/L | |||
| Baseline | 88.7 ± 28.5 | 63.9 ± 24.7 | 0.004 |
| Study-end | 97.8 ± 32.1* | 78.3 ± 25.3** | 0.028 |
| Plasma 1,25(OH)2D, geometric means (95% CIs), pmol/L | |||
| Baseline | 283 (232, 344) | 151 (129, 178) | <0.001 |
| Study-end | 303 (252, 364) | 163 (139, 191) | <0.001 |
| Plasma 24,25(OH)2D, geometric means (95% CIs), nmol/L | |||
| Baseline | 9.6 (7.5, 12.4) | 9.1 (6.7, 12.5) | 0.784 |
| Study-end | 11.4 (9.5, 13.8) | 11.7 (9.2, 15.0)** | 0.867 |
| Plasma DBP, geometric means (95% CIs), μg/mL | |||
| Baseline | 405 (319, 515) | 204 (164, 254) | <0.001 |
| Study-end | 370 (291, 470)** | 205 (166, 255) | <0.001 |
| Serum 3-epi-25(OH)D3, nmol/L | |||
| Baseline | 3.2 ± 2.1 | 1.9 ± 1.2 | 0.018 |
| Study-end | 4.5 ± 3.6* | 2.5 ± 2.2 | 0.035 |
| Free 25(OH)D, geometric means (95% CIs), pmol/L | |||
| Baseline | 16.0 (12.3, 20.8) | 19.5 (14.9, 25.5) | 0.291 |
| Study-end | 19.2 (15.1, 24.4)* | 25.7 (20.8, 31.7)* | 0.074 |
1
Data are presented as means ±SDs, unless otherwise indicated. The P value in each row indicates a significant difference between pregnant and nonpregnant women. An asterisk beside a vitamin D biomarker indicates a significant difference between baseline and study-end within either pregnant or nonpregnant women: *, P < 0.05. **, P < 0.01.
2
CYP2R1, 25-hydroxylase gene; DBP, vitamin D binding protein; 3-epi-25(OH)D3, C3 epimer of 25-hydroxyvitamin D3; GC, vitamin D binding protein gene; 25(OH)D, 25-hydroxyvitamin D; 1,25(OH)2D, 1,25-dihydroxyvitamin D; 24,25(OH)2D, 24,25-dihydroxyvitamin D.