Relationship between vitamin D status and the vaginal microbiome during pregnancy

Objective Evidence supports an inverse association between vitamin D and bacterial vaginosis (BV) during pregnancy. Furthermore, both the vaginal microbiome and vitamin D status correlate with pregnancy outcome. Women of African ancestry are more likely to experience BV, to be vitamin D deficient, and to have certain pregnancy complications. We investigated the association between vitamin D status and the vaginal microbiome. Study design Subjects were assigned to a treatment (4400 IU) or a control group (400 IU vitamin D daily), sampled three times during pregnancy, and vaginal 16S rRNA gene taxonomic profiles and plasma 25-hydroxyvitamin D [25(OH) D] concentrations were examined. Result Gestational age and ethnicity were significantly associated with the microbiome. Megasphaera correlated negatively (p = 0.0187) with 25(OH) D among women of African ancestry. Among controls, women of European ancestry exhibited a positive correlation between plasma 25(OH) D and L. crispatus abundance. Conclusion Certain vaginal bacteria are associated with plasma 25(OH) D concentration.