The number of recent sex partners among bisexual men in the United States.

CONTEXT: Little is known regarding bisexual men's number of recent sex partners, a risk factor for HIV and other STDs. Furthermore, it is unclear if bisexual men have more partners than heterosexual or homosexual men, and whether partner number varies by measures of sexual behavior, identity and attraction.
METHODS: Sexual orientation-defined separately by sexual behavior during the past year, identity and attraction-was assessed for 3,875 sexually active men aged 15-44 who had participated in the 2002 National Survey of Family Growth. Chi-square and t tests examined differences in background characteristics, behavioral risk factors and number of past-year sex partners by sexual orientation according to each definition. Multivariate ordinary least-squares regression was used to assess predictors of the number of partners.
RESULTS: When sexual identity and attraction were controlled for, behaviorally bisexual men were predicted to have had 3.1 more past-year partners than behaviorally heterosexual men and 2.6 more than behaviorally homosexual men. After controlling for sexual identity and behavior, bisexual-attracted men had had 0.7 fewer partners than homosexual-attracted men. In a model including background characteristics and behavioral risk factors, behaviorally bisexual men were predicted to have had 2.5-2.6 more partners than others. Neither bisexual identity nor bisexual attraction independently predicted the number of recent partners.
CONCLUSION: The way in which bisexuality relates to men's number of recent sex partners depends on how sexual orientation is measured. Interventions to reduce behaviorally bisexual men's number of partners will likely lessen their risk for HIV and other STDs.