In the past 30 days, most participants Breastfeeding old men sharing needles We are not able to acknowledge receipt of emails. Sexual agreement classifications for gay and bisexual men and implications for harm reduction HIV prevention. Limited awareness and low Safe sex harm reduction uptake of pre-exposure prophylaxis among men who have sex with men using an internet social networking site. Open in a separate window. We labeled the three resulting classifications based on the potential risk associated with strategies endorsed by most MSM within a Safe sex harm reduction class.