OBJECTIVE: To estimate the prevalence of fungal infection in cyclic vulvitis. METHODS: We retrospectively reviewed 40 cases of cyclic vulvitis. We examined the historic characteristics, physical findings, and laboratory results in this population, including the results of potassium hydroxide preparations of vaginal secretions and fungal cultures. RESULTS: The median age was 32 years and the mean duration of symptoms was 3.8 years. Thirty women (75%) reported prior antifungal therapies. Fungal cultures were positive in 24 of 39 (61.5%). Candida albicans was the species isolated in 13 of 24 cases (54%). Potassium hydroxide wet mounts contained evidence of fungal infection in 15 of 37 cases (40.5%). The sensitivity of the potassium hydroxide preparation was only 61%. Potassium hydroxide preparations were more sensitive when the species isolated was C albicans. CONCLUSIONS: Many women with cyclic vulvitis have positive vaginal fungal cultures. Potassium hydroxide preparations of vaginal secretions are not sufficiently sensitive to exclude fungal infection in this setting, possibly because of the relatively high incidence of fungal species other than C albicans. Fungal culture should be considered in the evaluation of women with recurrent episodes of vulvar discomfort, even when potassium hydroxide wet mounts do not contain fungal elements.