SISA Randomized Controlled Trial on the Effect of Sino-implant (II) Use on Condom Use Among Women in Kingston, Jamaica

This unblinded, randomized controlled trial (RCT) will assess whether the use of a contraceptive implant leads to more sex unprotected by a condom, as measured by the detection of a biological marker of exposure to semen in vaginal fluid, among women in Kingston, Jamaica. Eligible women will be non-pregnant, not known to be HIV-positive, 18-44 years of age, not already using a long-acting method of contraception, without contraindications to implant use, and willing to use the Sino-implant (II). Eligible women will be recruited from the Comprehensive Health Centre Center of Excellence (CHC) in Kingston, Jamaica and from the community. Women who give written consent for study participation will be enrolled in the study and randomized to one of the two study groups: 1) "immediate implant" insertion or 2) "delayed implant" insertion (i.e., when their study participation ends after three months of follow up). All participants will receive safer sex counseling, will be supplied with condoms, and will be administered a baseline questionnaire on demographics, reproductive history and contraceptive and sexual practices. A study clinician will perform a pelvic examination during which a double-headed vaginal swab will be collected to be tested for prostate-specific antigen (PSA), which is a semen biomarker. Participants will be asked to return for follow-up visits scheduled at 1 and 3 months after enrollment, at which times they will have another double-headed vaginal swab collected during a pelvic examination for testing for PSA and will be administered follow-up questionnaires. Participants in the "delayed implant" group will have the Sino-implant (II) inserted at the 3-month visit if they still want the device. Primary objective: To determine whether the frequency of PSA detection during three months of follow up is higher in the immediate implant group than in the delayed implant group.