Scarlett Alice Johnson first found fame as Dirty Den’s daughter Vicki Fowler in EastEnders. TV&Satellite Week magazine caught up with her to find out why she thinks her new BBC3 comedy Pramface [clip] could become a cult hit…

What’s Pramface about?
“It’s an unconventional journey through pregnancy with two teenagers. Laura, who I play, is 18 and Jamie [Sean Michael Verey], the boy involved, is 16. They meet at an end-of-exams party, have a drunken fumble and find themselves in bed together.”

Does the fact he’s so young worry you?
“No, he’s younger than her, but she’s too drunk to notice and he doesn’t tell her. Viewers will really feel for her. She’s doing really well at school and then she goes out one night to let her hair down and ends up pregnant. You start by thinking: ‘Oh, you poor girl, that’s such bad luck’. But it turns out that the boy is a really nice guy and a lot of really lovely stuff comes out of this unlikely situation. She goes off to university as planned and tries to stick it out and make it all work.”

BBC3 had a huge hit with Gavin and Stacey. Are you the next big rom-com following in their wake?
“Everyone on this channel wants to be the next Gavin and Stacey. I’d be really flattered if everyone who liked that show tuned in to ours.”

How did you research playing someone pregnant?
“I haven’t got my own children, but I was my elder sister Ellie’s birthing partner, so I had some experience of how beautiful, amazing and intense it all is. It brought it back to me quite how emotional that period was. I also watched a lot of One Born Every Minute.”

What did you learn from that?
“It was a valuable source of research material. There was one episode about teenage mums that was particularly helpful.”

Presumably you had props to help you in later episodes when you’re pregnant?
“Yes, I had various baby bumps of all sizes and comedy boobs to match. They were all weighted and had various belly buttons protruding. By the end they were getting quite silly. I’d walk around with them on, drinking coffee, and women would be looking at me and saying: ‘What? Are you doing drinking coffee?’ But it was quite liberating. I didn’t have that whole thing of thinking, ‘I’d better not eat that chocolate bar today’, because I knew I’d be wearing a fat suit so I could eat what I wanted.”

You have an impressive supporting cast of older actors…
“Yes, there’s Angus Deayton, Anna Chancellor and Bronagh Gallagher… They are all established performers in their own rights and they’re flipping hilarious. While we were filming in Edinburgh, we went out to see Ben Crompton, who plays Jamies’s dad, doing a stand-up comedy gig in Edinburgh. It was such a brilliant night. He’s such a funny guy. He had the whole place crying their eyes out with laughter.”

Did the university scenes bring back memories for you?
“No, I didn’t do go to university. I’ve been acting since I was a child. I was at the National Theatre when I was nine. That was my first job. But I’m now doing a part-time degree in archaeology and history, which is completely bonkers.”

Pramface begins on BBC3 on Thursday, February 23