The sexual behavior of sexual minority men in relationships is the subject of a lot of research. This is due, in part, to the prevalence of HIV in this population. Studies have examined sexual agreements and misunderstandings, commitment and sexual decision making, as well as drug use and sexual risk taking. A curious detail is evident in these studies. Condomless sex with a relationship partner and condomless sex with outside partners (any partner other than the primary relationship partner) tend to be positively correlated with one another, regardless of how these behaviors are assessed.
More, here.
