In order to study the role of promiscuity in yeast colonization of the vagina we examined vaginal smears of 197 prostitutes. Forty-two (21%) showed yeast infection on culture, and Candida albicans was isolated in 93% of these cases. This rate is comparable to the rates in reports of large series of non-promiscuous women in the literature and does not suggest that promiscuity alone is a predisposing factor for vaginal yeast carriage. The rate of Candida infections was approximately the same in prostitutes taking oral contraceptives as in those not taking the pill (22 and 21%, respectively; P > 0.05). The prevalence of vaginal yeast colonization, however, was significantly higher in prostitutes under the age of 31 (30%) as compared with those over 30 (10%; P < 0.002), thus suggesting that women in the third decade of life are more prone to vaginal Candida infections than older age groups.