Table 2.
Associations between maternal demographic and lifestyle factors and change in season-corrected serum 25(OH)D during pregnancy.
| Δ[season-corrected serum 25(OH)D] (nmol/l) | |||||||
|---|---|---|---|---|---|---|---|
| Univariate1 | Multivariate2 | ||||||
| n | β (95% CI) | p | n | β (95% CI) | p | ||
| Age at delivery (years) | 1752 | −0.0 (−0.3, 0.3) | 0.86 | ||||
| Ethnicity (Other vs White) | 1753 | 4.3 (−1.9, 10.5) | 0.17 | 1705 | 2.4 (−4.0, 8.7) | 0.46 | |
| Education to degree level or higher (yes vs no) | 1750 | 2.6 (−0.1, 5.3) | 0.06 | 1705 | 1.8 (−0.8, 4.5) | 0.18 | |
| Parity (Multiparous vs Nulliparous) | 1752 | −0.7 (−2.9, 1.5) | 0.54 | ||||
| Pre-pregnancy BMI (kg/m2) | 1741 | 0.1 (−0.2, 0.3) | 0.52 | ||||
| Smoking (yes vs no) | Early pregnancy | 1740 | −1.7 (−4.9, 1.5) | 0.30 | |||
| Late pregnancy | 1738 | −2.1 (−5.3, 1.2) | 0.21 | ||||
| Alcohol consumption (yes vs no) | Early pregnancy | 1736 | −2.0 (−4.8, 0.8) | 0.15 | 1705 | −2.1 (−4.9, 0.6) | 0.13 |
| Late pregnancy | 1738 | −0.1 (−2.6, 2.7) | 0.96 | ||||
| Moderate/Strenuous Exercise (Hours/week) | Early pregnancy | 1732 | 0.1 (−0.1, 0.4) | 0.25 | |||
| Late pregnancy | 1738 | 0.4 (0.1, 0.8) | 0.01 | 1705 | 0.4 (0.1, 0.7) | 0.01 | |
| ΔEarly to late pregnancy | 1717 | 0.9 (−0.1, 0.3) | 0.46 | ||||
| Weight gain early to late pregnancy (kg) | 1708 | −0.4 (−0.7, −0.1) | 0.003 | 1705 | −0.4 (−0.7, −0.1) | 0.003 | |
| Vitamin D supplement use (compared to never in pregnancy) | Early pregnancy only | 1722 | −7.4 (−10.3, −4.5) | <0.001 | 1705 | −7.3 (−10.1, −4.4) | <0.001 |
| Late pregnancy only | 11.9 (6.8, 17.0) | <0.001 | 12.6 (7.5, 17.8) | <0.001 | |||
| Early and late pregnancy | 6.5 (3.5, 9.5) | <0.001 | 6.6 (3.6, 9.7) | <0.001 | |||
1
P values were determined by univariate linear regression models of season-corrected 25(OH)D on maternal characteristics.
2
All associations from univariate analysis with p≤0.2 were included in the multivariable model. Statistically significant associations are in bold type.