Can I get that in writing?
When it comes to monogamy, a fair chunk of young high-risk Americans in relationships aren't playing by the same rules as their partners.
A new study reported in USA Today looked at 483 heterosexual and non-married couples aged 18 to 25 and found that in 40 per cent of the couples, only one partner said the couple had agreed to be monogamous.
(Caveat: The couples recruited for this study were considered to be at an increased risk for acquiring HIV or sexually-transmitted infections. We contacted one of the researchers, who told us that therefore, the study findings cannot be generalized broadly to all 18-25 year olds.)
The other? Never heard of this "monogamy."
Couples with children were less likely to have a monogamy agreement in place and married couples were no more likely than other couples to have an explicit monogamy agreement, according to USA Today. But commitment does play a role.
The more a couple scored on a commitment scale used in the study, the more likely they had a sustained agreement to be monogamous.
"Couples have a hard time talking about these sorts of issues, and I would imagine for young people it's even more difficult," researcher Marie Harvey, a professor of public health, said in a news release.
Still, even if everyone tried to say the M-word a little more, there are still no guarantees. The Oregon State researchers also found that among married couples who had agreed to have sex only with each other, about 30 per cent had strayed.
Tell us: Just how implied is monogamy is most relationships?
Editor's note: The study findings cannot be generalized broadly to all 18-25 year olds. An earlier version of this post made this generalization based on incorrect press release information. This has been corrected.