| dc.description.abstract | Background and Objectives: Gestational diabetes mellitus (GDM) is defined as any
degree of glucose intolerance occurring in or first recognizable during pregnancy. GDM
is considered to be a pregnancy complication. Worldwide, GDM prevalence varies from
1% to 28% of all pregnancies. Studies have shown that beta-cell dysfunction and insulin
resistance resulted excess weight gain during pregnancy intensify pregnancy-induced
insulin resistance. Some studies have shown that poor vitamin D status increases risks
for impaired insulin secretion, and insulin resistance. Vitamin D deficiency has been
reported in 80% of pregnant Iranian women. Therefore, this study was designed to
assess the effects of vitamin D supplementation on the metabolic profiles and hs-CRP
statuses of pregnant women with GDM.
Materials and Methods: The study was a randomized, placebo-controlled, doubleblinded clinical trial. Seventy-six pregnant women with GDM and gestational ages
between 24-28 weeks were randomly assigned to receive four oral treatments once
every 2 weeks for a total of 2 months that consisted of 50,000 IU of vitamin D3 (n = 38)
or placebo (n = 38). The fasting blood glucose (FG), insulin, HbA1c, 25-
hydroxyvitamin D, lipid profile, hs-CRP, and HOMA-IR were measured before and
after the treatment. For normally distributed data, we performed an independent
samples Student’s t-test, to detect basic differences between 2 groups, and a paired t-test
to detect differences in each group before and after the intervention. For nonparametric
distributions, we used the Mann-Whitney U test and the Wilcoxon paired rank test. To assess the effects of vitamin D supplementation on biochemical parameters between the
2 groups after the intervention, ANCOVA was used by adjusting for the baseline
measurements and covariates. Differences were considered to be significant at a P value
≤ 0.05.
Results: As compared with the placebo group, in the vitamin D group, the serum level
of 25hydroxyvitamin D increased (19.15 vs. -0.40 ng/ml; p < 0.01) and that of FG (-
4.72 vs. 5.27 mg/dl; p = 0.01) as well as HbA1c (-0.18% vs. 0.17%; p = 0.02)
decreased. There were improvements in the lipid profiles of the vitamin D group, but
they were not statistically significant. Significant increases in the concentrations of total
and LDL cholesterol as well as in fasting glucose, HbA1c, and hs-CRP were seen in the
placebo group. The fasting insulin and HOMA-IR did not change significantly in either
group.
Conclusion: Based on the results in GDM patients, vitamin D supplementation
improves FG, HbA1c, and vitamin D status but has no significant effects on lipid profile
or hs-CRP. Further studies are needed to determine more clearly the effect of vitamin D
on various biochemical markers in GDM patients. | en_US |
