Background: Vaginal microbicides have the potential to reduce HIV/STD acquisition when used consistently. Our objectives were to determine product attributes associated with willingness to use a vaginal microbicide and whether product preferences varied according to participant characteristics. Methods: Women (n=408) with bacterial vaginosis (BV) were recruited as part of a randomized trial to prevent BV. Participants completed a survey interview that assessed demographic information, sexual history, and douching behavior. To assess microbicide preferences, women rated whether specific product attributes would make them more or less likely to use a vaginal microbicide. Principal components analyses revealed two major groupings for the product attribute items. We determined the relative importance of each group of product attributes and whether the importance of the different groupings varied among subgroups of women. Results: The participants' mean age was 24 years (range 14-45), 64% were black, and 74% were unmarried. Overall, participants reported being most likely to use a vaginal product with protection properties (2.54), whereas they were nearly neutral regarding side effects (0.56). The individual product attributes, could prevent BV, could prevent vaginal odor (2.72), and could prevent vaginal itching and burning (2.61), were rated similarly or slightly higher than could reduce the risk of getting an STD (2.58) or could reduce the risk of getting HIV (2.44). In multivariate analyses, protection attributes were rated significantly higher among older women and marginally higher in women with a greater number of lifetime sexual partners. Younger women were most likely to report that side effects would affect their likelihood of using the product. Conclusions: Women with BV rated potential protection features of a vaginal microbicide higher than side effects. A product's personal hygiene aspects were rated equally or more important than the product's ability to prevent HIV/STD infections. Younger women may respond to different factors that influence product acceptability and adherence. © 2009 Mary Ann Liebert, Inc.