Sexual satisfaction is usually thought of in terms of number of orgasms and time spent between the sheets. But a new study finds that a person's reasons for doing the deed can influence how satisfied they are afterward.

The research, reported online Oct. 22 in the journal Archives of Sexual Behavior, finds that both men and women are more satisfied when having sex out of love and commitment, while mercenary types don't have much fun in bed — having sex to get material goods or to get ahead was associated with a less satisfying experience.

Why have sex?

Most research on sexual function and satisfaction focuses on arousal and orgasm, said study researcher Kyle Stephenson, a Ph.D candidate in the laboratory of University of Texas at Austin psychologist Cindy Meston. But people have sex for diverse reasons, not just for physical pleasure, Stephenson said. "What we wanted to do was just really to cast a wide net and see which [reasons] were associated with people being satisfied with their sex lives," Stephenson told LiveScience.

The researchers asked 544 college-aged men and women, most of them heterosexual, to take surveys on their sexual motivations and satisfaction.

Men who had sex to raise their self-esteem were less satisfied, as were men who had sex to get goods, favors or other resources.

Women had a broader range of associations, the researchers found. The connection between love/commitment and satisfaction was less strong for women than for men, though it was still present. Women who had sex to express something to their partner, like gratitude or apology, were also more satisfied.

Like men, women who had sex to acquire a self-esteem or resource boost were less satisfied. Having sex to have a new and exciting experience was also associated with less satisfaction.

Sex in context

The researchers aren't sure why more factors influenced women's satisfaction than men's. It may be that women play the sexual gatekeeper in many relationships, Stephenson said, so their motivations for sex are more likely to result in actual sex.

The next step, Stephenson said, is to look into how these motives play into people's level of distress over sexual dysfunction. Someone who has sex for love versus physical pleasure, for example, may be less worried if they don't orgasm regularly. The researchers also hope to expand the research beyond college students and into the wider population.

"[Sex] really is tied in with so many different variables related to the individual and the relationship and the larger culture," Stephenson said. "To come up with ways to think about sex as a science and as a society, it's important to at least attempt to understand these complex relationships."

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