Predictors of sexual risk reduction among Mexican female sex workers enrolled in a behavioral intervention study.

OBJECTIVE

We recently showed efficacy of an intervention to increase condom use among female sex workers (FSWs) in Tijuana and Ciudad Juarez, situated on the Mexico-United States border. We determined whether increases in condom use were predicted by social cognitive theory and injection drug user status among women randomized to this intervention.

METHODS

Four hundred nine HIV-negative FSWs aged >or=18 years having unprotected sex with clients within the prior 2 months received a brief individual counseling session integrating motivational interviewing and principles of behavior change (ie, HIV knowledge, self-efficacy for using condoms, and outcome expectancies).

RESULTS

Increases in self-efficacy scores were associated with increases in percent condom use (P = 0.008), whereas outcome expectancies were not. Female sex workers who inject drugs (FSW-IDUs) increased condom use with clients but not to the same extent as other FSWs (P = 0.09). Change in HIV knowledge was positively associated with change in percent condom use among FSW-IDUs (P = 0.03) but not noninjection drug users.

CONCLUSIONS

Increases in self-efficacy significantly predicted increased condom use among FSWs, consistent with social cognitive theory. Increased HIV knowledge was also important among FSW-IDUs, but their changes in condom use were modest. Enhanced interventions for FSW-IDUs are needed, taking into account realities of substance use during sexual transactions that can compromise safer sex negotiation.