Research Summary

Vitamin D supplementation reduces neonatal birth weight in gestational diabetes

Moderate confidence

Low bias

Last updated June 19, 2026

Key Takeaway:

This study examined the effects of vitamin D supplementation on oxidative stress, inflammation, and pregnancy outcomes in women with gestational diabetes mellitus, finding significant changes in several biomarkers.

Study at a Glance

What was studied

Vitamin D supplementation in women with gestational diabetes.

Participants

Young Adult (19–39), Middle Aged (40-64)

Female

with Gestational Diabetes

Intervention

Vitamin D supplementation, Placebo

Outcomes

Serum 25(OH)D, Calcium, Oxidative stress markers (GSH), Malondialdehyde (MDA), C-reactive protein, Neonatal birth weight, Incidence of macrosomia, Fasting glucose changes

Funding

Non-Industry Sponsored

Save this study and add notes to your research library.

Main Effects

Vitamin D supplementation significantly increased serum 25(OH)D levels by 6.38 ng/mL (p=0.021).

Calcium levels increased by 0.86 mg/dL (p=0.001) with vitamin D supplementation.

Vitamin D supplementation decreased MDA levels by 0.89 μmol/L (p=0.003) and hs-CRP levels by 1.28 mg/L (p=0.019).

Evidence Summary

Intervention	Outcome	Measured Change	Study Effect
Vitamin D supplementation (Supplements)	C-reactive protein (Metabolic Health)	Decrease	Strong
Vitamin D supplementation (Supplements)	Calcium (Metabolic Health)	Increase	Strong
Vitamin D supplementation (Supplements)	Fasting Plasma Glucose (FPG) (Glycemic Control)	No Change	Unclear
Vitamin D supplementation (Supplements)	Incidence of macrosomia (Clinical Outcomes)	Decrease	Strong
Vitamin D supplementation (Supplements)	Malondialdehyde (MDA) (Metabolic Health)	Decrease	Strong
Vitamin D supplementation (Supplements)	Neonatal birth weight (Weight & Anthropometrics)	Decrease	Strong
Vitamin D supplementation (Supplements)	Oxidative stress markers (GSH) (Metabolic Health)	Increase	Strong
Vitamin D supplementation (Supplements)	Serum 25-hydroxyvitamin D (Metabolic Health)	Increase	Strong

Unlock Full Evidence Analysis

Create a free account to access effectiveness ratings, evidence strength and depth scores, consistency analysis, and direct links to all supporting studies.

Evidence Suggest

Vitamin D increased serum 25(OH)D levels significantly.
Calcium levels rose notably with vitamin D supplementation.
Oxidative stress markers showed significant improvement.

Who this applies to

Pregnant women diagnosed with gestational diabetes mellitus.
Women in the study were likely in their second or third trimester.

Keep in Mind

The study's findings may not apply to all populations of pregnant women.
Further research is needed to understand the implications of lower neonatal birth weight.
Effectiveness of vitamin D supplementation on fasting glucose remains uncertain.

Between the Lines

The effectiveness of vitamin D supplementation remains unclear for some outcomes.
The study may have limited generalizability due to specific population characteristics.
No significant differences were found in fasting glucose changes.

Unlock Full Analysis

Create a free account to unlock the bias score, detailed effectiveness analysis, and clinical outcomes for this study.

Already have an account?

Journal Reference

Yifan L, Liying L, Jiani Y, Qin Y. Effects of Vitamin D Supplementation on Oxidative Stress, Inflammation, and Pregnancy Outcomes in Women with Gestational Diabetes Mellitus. Endocrine Connections. 2026;15(2):e250932. doi:10.1530/EC-25-0932

View DOI View on PubMed View on PMC

Connected Evidence

Discover how this study fits into the broader diabetes evidence landscape.

This study contributes to evidence on Vitamins, Minerals, and Nutraceuticals and Serum 25-hydroxyvitamin D, Vitamins, Minerals, and Nutraceuticals and Inflammatory and Oxidative Stress.