Effect of Vitamin D on the Vaginal Health of Menopausal Women: A Systematic Review.

Menopause is associated with the onset of climacteric symptoms due to low estradiol levels, which may cause insufficient maturation of the vaginal mucosa. Vitamin D may regulate the growth and differentiation of cells that are adversely affected due to low estradiol levels, thereby restoring vaginal health. The objective of this systematic review, the first on this subject, was to investigate the effect of vitamin D on the vaginal health of menopausal women. PubMed, Embase, Scopus, Web of Science, and Google Scholar databases and reference lists of hand-searched articles were searched for published studies from February 2000 to November 2018. The selection criteria were as follows: randomized or quasi-randomized trials that compared the effects of vitamin D or related compounds, alone or with calcium, on vaginal health (growth and differentiation of epithelial cells, dryness, acidity [pH]) outcomes in menopausal women. The methodological quality of these studies was examined using the Cochrane tool checklist by two independent investigators, following which the data were extracted. Of six examined studies, two showed that vitamin D administration improved the growth and differentiation of vaginal epithelial cells, improved vaginal pH, and decreased vaginal dryness in menopausal women. Although the level of evidence for the effects of vitamin D on vaginal health is low in our study, we concluded that vitamin D may improve the vaginal health of women, especially during menopause.