Vaginal rings address a critical need for an independently initiated, long-acting HIV prevention method, but their design must be acceptable to promote uptake and adherence. Human-centered design (HCD) may help address design preference questions. In two Phase I studies of vaginal rings for HIV prevention conducted in the United States, we used qualitative interviews to assess participants' perceptions and opinions of the physical characteristics of the ring they used and of a ring's physical characteristics after comparing four ring designs presented via a visual tool. Users were found to prefer ring designs that appear easy to use, are physically comfortable, that function well, and are aesthetically pleasing. The parameters for these features varied widely. Product developers and marketers should consider marketing messages in which the target users feel this product is made to meet their needs and desires. Product developers are encouraged to design using HCD early in ring development (Clinical Trial Registration number: NCT03234400 and NCT03670355).
