Table 1 Comparison of general factors among groups based on vitamin D status (Chi-square test, One-way ANOVA, and nonparametric test)
Parameters | n | 25(OH)D deficient (< 50 nmol/L)(n = 434) | 25(OH)D insufficient (50–74 nmol/L) (n = 882) | 25(OH)D sufficient (≥ 75 nmol/L) (n = 200) | P value |
|---|---|---|---|---|---|
Age (year) | 1516 | 29.57 ± 4.72 | 29.35 ± 4.55 | 29.35 ± 4.43 | 0.696 |
Intrapartum BMI (kg/m2) | 1516 | 26.77 ± 3.23 | 26.81 ± 3.31 | 26.54 ± 3.05 | 0.574 |
Parity | 1510 | Â | Â | Â | 0.073 |
 0 | 784 | 221 (50.9) | 457 (51.8) | 106 (53.0) |  |
 1 | 652 | 196 (45.2) | 380 (43.1) | 76 (38.0) |  |
  ≥ 2 | 80 | 17 (3.9) | 45 (5.1) | 17 (9.0) |  |
Season at sampling | 1516 |  |  |  |  < 0.001 |
 Spring | 547 | 257 (59.2) | 255 (28.9) | 35 (17.5) |  |
 Summer | 575 | 128 (29.5) | 365 (41.4) | 82 (41.0) |  |
 Autumn | 248 | 1 (0.2) | 176 (20.0) | 71 (35.5) |  |
 Winter | 146 | 48 (11.1) | 86 (9.8) | 12 (6.0) |  |
Gestational weeks at sampling | 1516 | Â | Â | Â | 0.181 |
 11 | 174 | 59 (13.6) | 87 (9.9) | 28 (14.0) |  |
 12 | 798 | 228 (52.5) | 460 (52.2) | 110 (55.0) |  |
 13 | 373 | 102 (23.5) | 232 (26.3) | 39 (19.5) |  |
 14 | 171 | 45 (10.4) | 103 (11.7) | 23 (11.5) |  |
Bone function | |||||
 Bone density Z value | 924 | -0.54(0.68) | -0.54(0.62) | -0.59(0.66) | 0.667 |
 Ca2+ (mmol/L) | 1478 | 1.37 ± 0.13 | 1.38 ± 0.13 | 1.38 ± 0.12 | 0.418 |
 Mg2+ (mmol/L) | 1477 | 1.33 ± 0.15 | 1.33 ± 0.15 | 1.31 ± 0.13 | 0.137 |
 ALP (IU/L) |  |  |  |  | 0.008 |
   < 45 | 63 | 27 (10.2) | 30 (5.2) | 6 (4.5) |  |
  45–125 | 822 | 221 (83.7) | 482 (84.0) | 119 (88.8) |  |
   ≥ 125 | 87 | 16 (6.1) | 62 (10.8) | 9 (6.7) |  |
Liver and kidney function | |||||
 Pre-ALB (mg/L) | 951 | 216.74 ± 30.95 | 224.64 ± 33.28 | 226.94 ± 33.26 | 0.002 |
 Pre-ALB (mg/L) |  |  |  |  | 0.769 |
   < 150 | 12 | 2 (0.8) | 8 (1.4) | 2 (1.5) |  |
   ≥ 150 | 939 | 255 (99.2) | 552 (98.6) | 132 (98.5) |  |
 Cre (µmol/L) | 1466 | 47.84 ± 7.01 | 46.78 ± 7.11 | 47.16 ± 7.99 | 0.047 |
 Cre (µmol/L) |  |  |  |  | 0.550 |
   < 41 | 234 | 60 (14.3) | 141 (16.5) | 33 (16.9) |  |
   ≥ 41 | 1232 | 359 (85.7) | 711 (83.5) | 162 (83.1) |  |
 Cys C (mg/L) | 323 | 0.97 ± 0.22 | 0.96 ± 0.21 | 0.94 ± 0.26 | 0.690 |
Coagulation function | |||||
 D-Dimer (mg/L) | 1431 | 0.37(0.24) | 0.39(0.23) | 0.38(0.23) | 0.232 |
 Fibrinogen (g/L) | 1437 | 3.98 ± 0.634 | 4.03 ± 0.67 | 4.05 ± 0.66 | 0.385 |
 aPTT (s) | 1437 | 36.28 ± 3.03 | 36.24 ± 2.86 | 36.65 ± 3.03 | 0.201 |
 TT (s) |  |  |  |  |  < 0.001 |
   < 14 | 192 | 28 (6.9) | 123 (14.7) | 41 (20.9) |  |
   ≥ 41 | 1245 | 379 (93.1) | 711 (85.3) | 155 (79.1) |  |
PLT (*10^9/L) | 1497 | 252.13 ± 54.48 | 250.32 ± 54.69 | 246.78 ± 53.46 | 0.521 |