"I started to really worry that I couldn't play this character if I didn't hurry up and mature a little," Mischa Barton said of playing Marissa Cooper
Mischa Barton
Credit: Paul Archuleta/Getty

As Mischa Barton's role on The O.C. catapulted her into TV stardom, she says she began to feel pressure to lose her virginity before she was ready.

In an essay for Harper's Bazaar U.K., published on Friday, Barton opened up about the personal impact some of her roles have had on her over the years.

Citing her time starring as Marissa Cooper on the former Fox series, the actress said she was "playing a confident character who was fast and loose" while she was "still a virgin" — which ultimately made her "feel like a fraud" since she wasn't sexually active like her character.

"The kids in the show were quintessential rich, privileged American teenagers drinking, taking drugs, and of course having sex. I knew it was important to get this thing — my virginity — that was looming over me, the elephant in the room if you will, out of the way," Barton, 35, recalled of the role she started playing at 17.

"I started to really worry that I couldn't play this character if I didn't hurry up and mature a little. Did I ever feel pressured to have sex with someone? Well, after being pursued by older men in their thirties, I eventually did the deed," she continued. "I feel a little guilty because I let it happen. I felt so much pressure to have sex, not just from him, but society in general."

A rep for Barton didn't immediately return PEOPLE's request for comment. The former show's distributor, Warner Bros. Television, and a rep for O.C. creator-executive producer Josh Schwartz declined to comment.

Barton also reflected on her experience working on mature content from a young age. She began by discussing her debut film role in Lawn Dogs, which examined child molestation.

the oc - Mischa Barton
Credit: Warner Bros Tv/Kobal/Shutterstock

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"While the crew did everything to ensure that I wasn't exposed to the realities of what all that meant — when I did press for the film, it became clear that it was very mature content," she wrote. "Two years later, I did Pups with Burt Reynolds. Lead roles in coming-of-age films are always directly tied to sex and sexuality, and this was a prime example. It was for Pups that I had my first kiss on screen and in real life, in front of an entire crew."

The Hills: New Beginnings alum added that her Pups character "had her first period in one scene," which is something Barton hadn't yet experienced in real life. "The movie blew up in Asia, and I became a strange sex symbol over there," she said. "I was 13."

Barton's candid essay comes after she claimed to have experienced "bullying" from "some of the men on set" of The O.C. before her eventual exit.

"There were people on that set that were very mean to me," she told E! News last month. "It wasn't, like, the most ideal environment for a young, sensitive girl who's also been thrust into stardom to have to put up with."

Barton starred on The O.C. from the first season in 2003 until 2006's season 3 when her character was killed off in a car crash.