24 February 2026 : Clinical Research
Effects of Age, Season, and Pregnancy History on Vitamin D Status in Women Seeking Preconception Care
Manyu Wu BCDEF 1,2, Dan Liu ABCDEF 1*DOI: 10.12659/MSM.950280
Med Sci Monit 2026; 32:e950280
Table 5 Mixed-effects linear regression analysis of 25(OH)d levels with age, season, adverse pregnancy history, and pregnancy history in women undergoing preconception care.
| Item | Unstandardized coefficient | Standardized coefficient | t value | P | 95% Confidence interval for B | ||
|---|---|---|---|---|---|---|---|
| B | Standard error | Bate | Lower bound | Upper bound | |||
| Constant | 14.295 | 1.307 | – | 10.935 | <0.001 | 11.730 | 16.861 |
| Age | 0.160 | 0.044 | 0.116 | 3.630 | <0.001 | 0.073 | 0.246 |
| Adverse pregnancy history | 0.194 | 0.517 | 0.014 | 0.376 | 0.707 | −0.820 | 1.209 |
| Pregnancy history | 1.773 | 0.458 | 0.156 | 3.871 | <0.001 | 0.874 | 2.671 |
| Season (Winter) | −1.627 | 0.499 | −0.120 | −3.262 | 0.001 | −2.606 | −0.649 |
| Season (Spring) | −2.411 | 0.467 | −0.193 | −5.162 | <0.001 | −3.328 | −1.495 |
| Season (Summer) | −1.159 | 0.458 | −0.096 | −2.533 | 0.011 | −2.057 | −0.261 |