Condom use with "casual" and "main" partners: what's in a name?

OBJECTIVE: This study examined adolescents' attitudes about and behaviors toward condom use with "casual" vs. "main" sexual partners.
METHOD: Participants were sexually active adolescents aged 15-21 years (n = 1316) recruited from primary care clinics and through outreach activities in three major cities in the United States. Assessment of condom use within the past 90 days, relevant attitudes, substance use, and demographic data were obtained via audio computer-assisted self-interview (ACASI).
RESULTS: Participants were divided into two groups: the 65% who reported main partners only (MP group) and the 35% who had at least one casual partner (CP group). Adolescents in the MP group were more likely to be female, whereas males were significantly more likely to report casual partners. Race/ethnicity, age, education level, household income, and sexually transmitted infection (STI) history were unrelated to group status (i.e., sexual partner type). Greater substance use and riskier attitudes were reported by teens in the CP group. The number of unprotected sex acts in the past 90 days was substantial and equivalent between the main and casual partner groups (19.2 vs. 21.5, respectively). Regression analyses revealed that perceptions of main partner attitudes toward condom use and condom use expectations were significantly related to condom use with MPs, but that attitudes were not related to condom use with CPs.
CONCLUSIONS: Adolescents with either casual or main partners may be at continued risk for contracting human immunodeficiency virus (HIV) and STIs, given high rates of unprotected sex. Interventions that do not target attitudes and practices related to casual partners as compared with main partners may miss an opportunity to change risk behaviors. This study demonstrates the importance of understanding an adolescent's perception of partner types in order to design effective interventions.