Celebrities like Snooki and Kim Kardashian have always been open when it comes to discussing their personal lives, and sex is no exception. It turns out, however, they were shockingly young when they lost their virginity!

Mario Lopez, for example, was just 12 years old when he lost his virginity, which he admitted in his memoir Just Between Us. The Extra host even said that sex was his "drug of choice" throughout his adolescent and young adult life.

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“I know I made my share of mistakes, and sometimes big ones,” he said. “I had to learn all my lessons the hard way… I started having sex so young. The day before my 13th birthday. Now that I’m a dad, I look back and I think, ‘Oh my God!’ But you’ve got to understand, when you’re growing up in the hood, everybody grows up fast.”

The actor even revealed that he got a girl pregnant when he was a teenager, but she decided to terminate the pregnancy. “I could have a kid who is 25 years old," he explained. "That’s unbelievable."

Click through the gallery to see more stars who were younger than 16 years old when they first had sex.