Vaginal yeast colonization in nonpregnant women: a longitudinal study.

OBJECTIVE We sought to investigate the prevalence and risk factors for vaginal yeast colonization over a 1-year period. METHODS We conducted a longitudinal cohort study of 1,248 asymptomatic young women by collecting demographic and behavioral data at baseline, 4, 8, and 12 months. RESULTS Seventy percent of women were colonized by vaginal yeast at one or more visits, but only 4% were colonized at all 4 visits. Using an adjusted generalized estimating equation model, factors associated with vaginal yeast colonization were marijuana use in the previous 4 months, depomedroxyprogesterone acetate use in the past 4 months, sexual intercourse in the previous 5 days, and concurrent colonization with lactobacilli and group B streptococcus. Symptoms of pruritus and vulvovaginal burning were associated with yeast colonization, but antifungal use was not. CONCLUSION Recent sexual intercourse and use of injection contraceptives are risk factors for yeast colonization. Rates of antifungal use did not show an association with yeast colonization. The reporting of antifungal use by women lacking yeast colonization suggests that self-diagnosis is inaccurate. LEVEL OF EVIDENCE II-2.