Relationship between Circulating Vitamin D Concentration and the Maternal Gut Microbiota during Early Pregnancy in Japanese Women: Results of a Pilot Study of Antenatal Vitamin D3 Supplementation.

What Was Tested

This randomized controlled trial looks at Vitamin D, K2, Magnesium and Zinc.

However, the relationship between vitamin D and the gut microbiota during pregnancy has not been evaluated in detail.

In this study, the researchers administered a vitamin D3 supplement (VD) to pregnant Japanese women, starting during the first trimester of pregnancy, and characterized changes in the circulating concentration of vitamin D and the gut microbiome.

Who Took Part

PubMed indexes the participants as young adults and adults, women only.

How the Study Was Run

The design is described as randomized and pilot.

Random assignment meant chance, not the researchers, decided who got Vitamin D, K2, Magnesium and Zinc and who got the comparison, which limits bias.

It is described as a pilot, a small early test of whether a larger Vitamin D, K2, Magnesium and Zinc study would be practical.

What Was Measured

However, the relationship between vitamin D and the gut microbiota during pregnancy has not been evaluated in detail.

Topics PubMed links to this paper include Gastrointestinal Microbiome, Cholecalciferol, Pilot Projects, Dietary Supplements, Vitamin D, Japan and Vitamin D Deficiency.

The authors tagged it with the keywords gut microbiota, pregnant Japanese women, serum 25(OH)D concentration and vitamin D3 supplement.

What This Means in Plain Language

The paper is a randomized and pilot study of Vitamin D, K2, Magnesium and Zinc.

The publication is from 2025 (Journal of nutritional science and vitaminology), a journal based in Japan.

More context: the Vitamin D, K2, Magnesium and Zinc compound page, all human trials.