A Comparison of Young Womens Actual and Assigned Timing-of-Use of a Microbicide Surrogate

Purpose: This study examined young women's actual timing of use of a microbicide surrogate gel (vaginal moisturiser (VM)) compared with assigned timing conditions. Methods: Participants used a VM with coitus during 4- week cycles over a 3-year period in random timing sequences: 1h before coitus, 10min before coitus and 10min after coitus. Daily diaries collected information related to coital behaviours, VM use and timing, and participants' and partners' VM assessments. Descriptive and mixed-effects model analyses were conducted. Results: At least three VM timing conditions were completed by 109 women aged 18-22 years old. Of 17 772 diary days collected, coitus was reported on 2128 (1252 with VM use; 59%). Median times between VM application and coitus were: 60min before coitus (mean=68.2; s.d.=76.9) for the 1-h pre-coital group, 13.5min before coitus (mean=44.9; s.d.=117.1) for the 10-min pre-coital group and 5min before coitus (mean=24.5; s.d.=205.1) for the 10-min post-coital group. Women reported that the VM was very easy to use (68%), it was somewhat messy (61%), they were very wet during sex (81%), sex was very good (80%) and their partners liked using the VM (38%). Conclusions: Overall, the VM was rated positively. There was substantial deviation in application time across timing conditions, with significantly greater variability in the post-coital group. These findings contribute to understanding of how VMs are accepted and used, with implications for HIV prevention with microbicides requiring specific application timing. Additional keywords: acceptability, application, HIV prevention, STI prevention, vaginal microbicide.