Seth Rogen at the "Knocked Up" premiere in Los Angeles, CA. May 21, 2007.
Jill Johnson/Jpistudios.com

Us Weekly calls Knocked Up, "the summer's best comedy!" It stars Grey's Anatomy's Katherine Heigl and The 40-Year-Old Virgin's Seth Rogen as an unlikely duo brought together by an accidental pregnancy. Though Rogen just turned 25, the Canadian actor and writer has been making audiences laugh since his role on the critically acclaimed NBC dramedy, Freaks and Geeks. At a press conference for the movie, which opens in theatres today, he joked about filming a sex scene, starting as a stand-up at age 13, and improvising on-set. Read excerpts below!:

On getting sexy with co-star Katherine Heigl:
"It’s kind of nerve-wracking, you know? You're dry humping a girl you don’t know very well. I was just afraid I was going to sweat on her. That was my major concern: I was going to drop a big gob of sweat onto her head. Luckily, they’re comedic sex scenes."

On keeping his character, Ben, likeable:
"You can have people say all the filthy despicable things you want...as long as you get that the character is trying to be a good person through it all. It’s simple, but emotionally speaking, it’s true to my experience with people. You meet someone and they have their shortcomings, but as long as they’re trying to do well by others then you know they’re redeemable."

On doing stand-up at 13 in Vancouver:
"I didn’t work blue back then. Mostly because my mother came to my shows. I was embarrassed. My life wasn’t that R-rated back then: I was trying to be truthful with what was going on with my life and my friends. It was more about my grandparents and videogames and my bar mitzvah. I hadn’t yet delved into the filthy world I now occupy."

On straying from the script:
"There was tons of improv on all the scenes. Especially the ones with me and my friends. We hired my actual friends. Because we always hope that those dynamics show on film, and our hope was that you’d be able to tell we’re actually friends and we know each other well. We'd shoot the script once or twice and then go off. Harold Ramis put it really well. I was talking to him and he said about Ghostbusters, ‘The script was the worst case scenario. The script was what we had if we couldn’t think of anything better.’ And that’s what we do, and it was a great script to begin with."

On shooting the labor scene:
"I was a big proponent of showing the whole 'mcgillah,' as they say. I thought it’d be funny and shocking and it reminded me of Something About Mary where you see Ben Stiller’s zipper and crotch. It’s always implied in movies. It’s never really 100 feet tall and I just knew that reaction would be fun from the audience. It was stressful to shoot that scene. [Katherine Heigl] actually pushed out her back from screaming and pushing so much. I just had to kind of stand there and hold her hand. I felt like I imagine a real husband feels at a birth, which is: it’s her show, stay out of her way and try not to ruin anything. It was weird to film.

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