Table 1.
Characteristics of the women including in the analysis, and where available in comparison to women from the Southampton Women’s Survey for whom serum 25(OH)D was not measured in both early and late pregnancy
| 25(OH)D measured in both early and late pregnancy |
25(OH)D not measured in early and late pregnancy |
P1 | ||
|---|---|---|---|---|
| n | 1753 | 1405 | ||
| Maternal age at delivery (years), mean (SD) | 30.4 (3.7) | 31.0 (4.0) | <0.001 | |
| White ethnicity (%) | 96.8 | 94.0 | <0.001 | |
| Education to degree level or higher (%) | 22.2 | 21.7 | 0.74 | |
| Nulliparous (%) | 48.3 | 54.6 | <0.001 | |
| Pre-pregnancy BMI (kg/m2), median (IQR) | 24.2 (21.9-27.4) | 24.1 (21.8-27.3) | 0.28 | |
| Current smoker (%) | Early pregnancy | 13.9 | 19.2 | <0.001 |
| Late pregnancy | 13.5 | |||
| Consumed alcohol in last 14 weeks (%) | Early pregnancy | 80.1 | ||
| Late pregnancy | 77.9 | |||
| Moderate/Strenuous exercise (hours per week), median (IQR) | Early pregnancy | 1.25 (0.25-3.25) | ||
| Late pregnancy | 0.75 (0.13, 2.25) | |||
| Weight gain early to late pregnancy (kg), mean (SD) | 10.7 (4.3) | |||
| Dietary vitamin D intake (iu/day), median (IQR) | Early pregnancy | 129 (91-169) | ||
| Late pregnancy | 135 (98-178) | |||
| Vitamin D supplementation usage (%) | Early pregnancy | 37.3 | ||
| Late pregnancy | 22.2 | |||
| Serum 25(OH)D (nmol/l), median (IQR) | Early pregnancy | 61 (43-81) | ||
| Late pregnancy | 59 (41-84) |
1
p values were determined using t-tests, Mann-Whitney and χ2 tests for normally distributed, non-normally distributed and categorical outcomes, respectively.