Vitamin D Insufficiency Linked To Bacterial Vaginosis In Pregnant Women

Vitamin D may play a role in BV because it exerts influence over a number of aspects of the immune system.

This hypothesis is circumstantially supported by the fact that BV is far more common in black than white women, and vitamin D status is substantially lower in black than white women. This relation, however, has not been rigorously studied. To assess whether poor vitamin D status may play a role in predisposing a woman to BV, Bodnar and coworkers at the University of Pittsburgh and the Magee-Womens Research Institute studied 469 pregnant women.

This prospective epidemiologic study investigated the relation between vitamin D status and BV in 209 white and 260 black women at <16 wk of pregnancy with singleton gestations. Blood samples were taken, and serum analyzed for 25-hydroxyvitamin D [25(OH)D], a marker of vitamin D status. 25(OH)D levels below 80 nmol/L are typically considered insufficient. Pelvic examinations were performed, and Gram-stained vaginal smears were assessed to diagnose BV.

The data indicate that 41% of all enrolled women had BV, and that 93% had 25(OH)D levels indicative of vitamin D insufficiency. Overall, women with BV had lower serum 25(OH)D concentrations than those without BV (P < 0.01). The prevalence of BV decreased as vitamin D concentration increased to 80 nmol/L (P < 0.001). Compared with 75 nmol/L, serum 25(OH)D concentrations of 20 nmol/L and 50 nmol/L were associated with 65% and 26% increases, respectively, in the likelihood of BV. In summary, these findings suggest that vitamin D insufficiency is associated with BV in the first 4 mo of pregnancy. Further, poor vitamin D status may contribute to the strong racial disparity in the prevalence of BV in US women. Controlled intervention trials will be needed to confirm this hypothesis.