Correlates of unprotected anal intercourse: the influence of anal sex position among men who have sex with men in Beijing, china.

Understanding barriers to consistent condom use among men who have sex with men (MSM) requires consideration of the context in which risk behaviors occur. Anal sex position is one such context. This pooled cross-sectional study used survey data from 1,230 MSM and their 2,618 reported male sexual partnerships. Overall, nearly half of the participants engaged in unprotected anal intercourse (UAI) with at least one of upto three partners in the past 6 months. "Insertive" men engaged in less UAI (39 %) than "receptive" (53 %) or "versatile" (51 %) men. Regardless of sexual position, UAI was associated with cohabiting with a male or female partner and perceiving great or moderate risk of HIV from male contact at the individual level, and steady (vs. casual) partnership at the dyad level. However, early MSM anal sex debut, high number of male partners, alcohol use, receiving and buying condoms, HIV testing, and MSM sex-seeking venues were found to be only statistically significantly correlated with UAI among some but not all sexual positions, implying that interventions to increase condom use should take into account how anal sex position may influence willingness and ability to engage in safer sex. Dyad level data appear to provide additional insight into the influence of sexual positions, and should be used to complement individual data for future intervention designs.