Maternal vitamin D deficiency is associated with bacterial vaginosis in the first trimester of pregnancy.
Bacterial vaginosis (BV) is a highly prevalent vaginal infection that is associated with adverse pregnancy outcomes. Vitamin D exerts an influence on the immune system and may play a role in BV. The objective of this study was to examine the association between maternal vitamin D status and the prevalence of BV in early pregnancy. Women (n = 469) enrolled in a pregnancy cohort study at <16 wk underwent a pelvic examination and provided a blood sample for determination of serum 25-hydroxyvitamin D [25(OH)D]. BV was diagnosed using Gram-stained vaginal smears interpreted using the method of Nugent. Approximately 41% of women had BV (Nugent score 7-10) and 52% had a serum 25(OH)D concentration <37.5 nmol/L. The mean unadjusted serum 25(OH)D concentration was lower among BV cases (29.5 nmol/L; 95% CI: 27.1, 32.0) compared with women with normal vaginal flora (40.1 nmol/L; 95% CI: 37.0, 43.5; P < 0.001). BV prevalence decreased as vitamin D status improved (P < 0.001). Approximately 57% of the women with a serum 25(OH)D concentration <20 nmol/L had BV compared with 23% of women with a serum 25(OH)D concentration >80 nmol/L. There was a dose-response association between 25(OH)D and the prevalence of BV. The prevalence declined as 25(OH)D increased to 80 nmol/L, then reached a plateau. Compared with a serum 25(OH)D concentration of 75 nmol/L, there were 1.65-fold (95% CI: 1.01, 2.69) and 1.26-fold (1.01, 1.57) increases in the prevalence of BV associated with a serum 25(OH)D concentration of 20 and 50 nmol/L, respectively, after adjustment for race and sexually transmitted diseases. Vitamin D deficiency is associated with BV and may contribute to the strong racial disparity in the prevalence of BV.
Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA 15261, USA. bodnar@edc.pitt.edu
Lisa M
LM
Bodnar
Marijane A
MA
Krohn
Hyagriv N
HN
Simhan
D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology*; D011261:Pregnancy Trimester, First; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D016585:Vaginosis, Bacterial / Q000150:complications* / Q000453:epidemiology; D014808:Vitamin D Deficiency / Q000150:complications*; D055815:Young Adult