Could you juggle multiple romantic relationships at one time — if each of your partners knew about the others? How about setting up your household as a triad, rather than a couple?

And what do you think of people who do such things?

Chances are, the more you know about the relationship style called polyamory, the more accepting you are of such setups, according to new research. The findings echo what psychologists know about how people respond to gays, lesbians and other sexual minorities: The greater the familiarity, the less severe the stigma.

"If people know even one gay person that they like in their life — a friend, a relative — their attitudes are much more favorable," said study researcher Traci Giuliano, a psychologist at Southwestern University in Texas. Likewise, the study found that "the more aware people were of polyamory, the more positive their attitudes were," Giuliano told Live Science. [5 Myths About Polyamory, Debunked]

Polyamory's popularity

Polyamory is often confused with swinging, but the terms are not interchangeable. Unlike swingers, who go outside their primary relationship for sex only, polyamorous people maintain simultaneous romantic ties, all with the consent and knowledge of everyone involved.

It's unclear how many people identify themselves as polyamorous, but a 2013 study in the journal Analyses of Social Issues and Public Policy estimated that between 4 percent and 5 percent of people in the United States are involved in some sort of consensually nonmonogamous relationship.

What's clear is that polyamory is moving out of the underground, with shows like Showtime's "Polyamory: Married & Dating" bringing the lifestyle to a broader audience. However, polyamory remains stigmatized: A 2013 survey of nearly 4,000 polyamorous people found that 28.5 percent had personally experienced discrimination because of their relationship style.

Giuliano was interested in researching this stigma in part from personal experience. Though she is not polyamorous, Giuliano is in a relationship that can seem unfamiliar to some people. She is "not generally attracted to women," Giuliano said, but she fell in love with and is married to a woman.

"This is just so confusing to people," she said. But once people get to know her, she added, they are generally accepting and tolerant.

She said she wondered if the same familiarity effect might benefit polyamorous people. For the study, she and her colleagues gave 100 people between ages 18 and 63 an online survey about their understanding and attitudes toward polyamory. The researchers found that 60 percent of the respondents knew what the term meant, and 30 percent personally knew someone who had been or was in a polyamorous relationship.

People's perceptions of the polyamorous individuals were somewhat negative, however. Polyamorous people were seen as being particularly promiscuous, as having high sex drives and as participating in unsafe sex. (The latter is particularly untrue, Giuliano noted, as a basic tenant of polyamory is communication about sexual practices. A 2012 study in the Journal of Sexual Medicine found that polyamorous people are actually better about protecting themselves against sexually transmitted infections than are nominally "monogamous" people who cheat on their partners.)

Changing attitudes

Unsurprisingly, the people in the study who reported having more traditional and religious values were less accepting of polyamory, Giuliano said.

The next step was to see if those attitudes would budge.

In a second survey, the researchers recruited 196 people, 18 to 79 years old. A third of the participants read a brief definition of polyamory and then answered questions; another third got a longer, more in-depth description of polyamory. A final third saw a definition and then were encouraged to think about the pros and cons of monogamy in their own lives.

The people in the group that read the in-depth definition as well as those in the thought-exercise group exhibited more positive attitudes toward polyamory afterward, the researchers reported.

The results show that people's perceptions can change, Giuliano said. "There are things that we can do to improve people's attitudes," she said.

Lessening the stigma of polyamory is a good thing, Giuliano said. She said she'd next like to study how particular facets of polyamorous relationships lessen such stigma. Perhaps people are open to polyamory only up to a certain number of people in the relationship, or if it involves people of only certain sexual orientations, for example, she said.

"These people are here," she said of those who practice polyamory. "They're not going anywhere, and they're going to suffer from prejudice and discrimination."

Monogamous individuals might also have something to learn from polyamorous people, Giuliano added, even if one partner seems like plenty: Polyamorous ideals demand that partners maintain open communication, negotiate their boundaries and are treated as equals.

"All relationships can benefit from mutual trust, respect, and open and honest communication," Giuliano said.

The researchers reported their findings online Jan. 30 in the journal Psychology & Sexuality.

Follow Stephanie Pappas on Twitter and Google+. Follow us @livescience, Facebook & Google+. Original article on Live Science.