Next time you walk past a group of young women who sound like they're growling at each other, don't worry; it's no catfight. It's only vocal fry, that guttural, vibrating sound you hear when a voice temporarily drops to its lowest register.

Lady Gaga, Britney Spears and Ke$ha use vocal fry for dramatic effect in their songs. As pointedly parodied on "SNL," Kim Kardashian is a frequent fryer. But so are more respected young celebrities like Scarlett Johansson, Emma Stone and Zooey Deschanel.

Everyone does it occasionally. But lately, vocal fry has been creeping into the conversations of young women more often, say speech pathologists and singing instructors. A recent study of 34 female college students conducted by researchers at Long Island University in New York heard vocal fry in the voices of more than two-thirds of them, especially at the ends of sentences. The researchers speculate that the students may "have either practiced or observed this vocal register and modeled it to match popular figures."

One study of 34 subjects doesn't exactly scream epidemic. But Twin Citians who make their living from listening to others' voices have noticed a trend, including Andrew Fleser, a vocal coach with the McNally Smith College of Music in St. Paul.

"A lot of the coaching work I do focuses on diction, so I'm always listening to the way people talk and notice when they're not projecting," he said. "I hear it everywhere, more among women than men. It's rampant among segment reporters on NPR."

Andrea Leap, a vocal instructor at MacPhail Center for Music, also has been hearing a "chronic lower speech pattern in the voices of young women, both in film and TV and in general."

At a MacPhail department meeting, Leap said, voice teachers were talking about vocal fry as being a chronic problem with younger singers. When taken to extremes, some experts say it could cause permanent damage to vocal cords, which may have already happened to one of last year's biggest pop stars, Adele, who has had surgery on hers.

"I love her voice, but you can't listen to it and think harm isn't being done," Leap said. "Vocal fry can cause damage just like any other misuse of the vocal cords."

While some reputable classical voice teachers actually use "frying" as a strengthening technique for their students, she said, "when you're 18 and you sound like Kathleen Turner, something's not right."

Vocal fry, once classified as a speech disorder, is the lowest of three registers in the human voice, the other two being modal (normal) and falsetto. You might call it the opposite of Valleygirl-speak, which favors squeaky upticks in register at the end of sentences ("So he was all, really? And I was all, huh?"). Vocal fry brings the tone way down, so far down that the only sound coming out is a kind of rat-a-tat static from the back of the throat.

In this case, though, "low" doesn't translate as serious or authoritative. Most fryers who aren't professional singers won't do damage to their vocal cords, but their reputations are another matter.

"It seems like a sort of laziness that can make you sound less polished," Fleser said.

Kate Bringardner, who coaches executives on vocal dynamics in the workplace, agrees.

"The Fry can drain words and thoughts of any vitality and weight," she wrote on her blog. "It's a vocal shrug of the shoulders ... the newest way for women to express their opinion without being threatening."