Vitamin D and Sexual Health (DASH)

Bacterial vaginosis (BV) develops when the concentration of healthy Lactobacillus species in the vagina declines and is replaced by other bacterial species. BV is the most common vaginal infection worldwide, but the etiology of this complex condition is not clear. BV is associated with a 60% increased risk of HIV acquisition as well as numerous other detrimental reproductive outcomes. A profound racial disparity exists in BV prevalence in women in the United States (US): 23% of white women versus. 52% of black women have BV. The investigators hypothesize that inadequate vitamin D contributes to BV development and/or recurrence. Vitamin D is essential to immune function, serving both to stimulate mechanisms associated with pathogen elimination and to regulate immune response. According to nationally-representative data, 90% of US blacks have insufficient vitamin D levels. In two recent analyses, low vitamin D was associated with higher BV prevalence in pregnant African-Americans; a third replicated this finding in pregnant African-American and white women. The investigators wish to conduct a small, pilot randomized controlled trial (RCT) to assess the effect of vitamin D supplementation among non-pregnant, BV-positive women at a public sexually transmitted disease (STD) clinic. This small (n=150), two-arm, placebo-controlled, masked, 24-week RCT of high-dose vitamin D supplementation will inform the development of future large-scale RCT design and implementation.

Women in the vitamin D arm take 50,000 international units (IU) of vitamin D3 (cholecalciferol) weekly for four weeks (end of week 1, week 2, week 3 and week 4), then every 4 weeks through 24 weeks of follow-up (end of week 8, week 12, week 16, week 20 and week 24) for a total of 9 treatments

Women in the placebo arm will take their matching supplement weekly for four weeks (end of week 1, week 2, week 3 and week 4), then every 4 weeks through 24 weeks of follow-up (end of week 8, week 12, week 16, week 20 and week 24) for a total of 9 treatments

To assess the effect of vitamin D supplementation on levels of and correlations between BV-associated and vitamin D-associated immunoinflammatory mediators after 24 weeks

Inclusion Criteria: speak English; be between 18 and 50 years old, inclusive; be pre-menopausal; have at least one ovary; be positive for bacterial vaginosis Exclusion Criteria: pregnant at enrollment or in the previous 3 months; planning to become pregnant in the next six months; currently breastfeeding; currently be menstruating heavily; have a contraindication to oral metronidazole treatment

Turner AN, Carr Reese P, Fields KS, Anderson J, Ervin M, Davis JA, Fichorova RN, Roberts MW, Klebanoff MA, Jackson RD. A blinded, randomized controlled trial of high-dose vitamin D supplementation to reduce recurrence of bacterial vaginosis. Am J Obstet Gynecol. 2014 Nov;211(5):479.e1-479.e13. doi: 10.1016/j.ajog.2014.06.023. Epub 2014 Jun 17.