Predicting concurrent sexual behavior among a sample of heterosexual men and women at risk for HIV/STIs

One known risk factor for HIV/STI acquisition is engaging in sexual relationships with multiple partners at the same time or within short intervals. Little is known, however, about the interpersonal dynamics that give rise to concurrent sexual partners. Focusing on individuals who initially reported sexual behavior exclusively with one partner, we used data from a longitudinal study that examined relationship dynamics within the heterosexual involvements of young men and women to predict which participants would initiate sexual relations with an additional partner over time. Men (N=261) and women (N=277) were recruited from Los Angeles and completed four in-person interviews at four-month intervals over one year. At Time 1, measures of commitment to and investments in the relationship with the sexual partner and proportion of condom-protected acts of intercourse with that partner were collected. At Time 2, data on the status of that relationship (intact vs. dissolved), and involvement/protected acts with an additional sexual partner were obtained. Commitment level at Time 1 significantly predicted whether the initial partnership had remained intact and whether the participant initiated a new sexual relationship between Time 1 and 2. Investment at Time 1 also significantly differentiated those who initiated a new sexual relationship. Among those participants who reported additional partners at Time 2, the rate of condom use was generally high with new partners (>60%); however, the rate of condom use with the original partner remained low (<33%). Additional results from multivariate analysis and implications for couple-based prevention programs will be discussed.