Coronation Street's Sally Carmen said Abi Franklin's pregnancy was a 'complete surprise'.
In dramatic scenes that aired on Sunday, Abi went into labour after a binge drinking and drugs session.
Finding her in a terrible state, her husband Kevin Webster kicked her out of the house.
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Abi ended up in a car with Dean Turnball, who panicked when he thought she was overdosing.
Leaving her at the side of a country road, Abi called for an ambulance and told the operator: "I'm having a baby."
However, fans aren't sure if Kevin is the father of Abi's child after her one night stand with Imran Habeeb.
Speaking to OK, Sally said her “jaw dropped to the floor” when she heard about it from producer Iain McLeod.
She said: “We had a chat, and Ian didn't pause for breath. He was speaking for about forty minutes.
"And it was just like – and then this happens, and this happens. And my jaw is falling further and further on the floor.
“I think I said about two words. I think the two words were: “Thank you.” That literally was it. I was like: “This is amazing.”
“I mean, it's just awesome. Just brilliant. I just can't quite believe I get to do another brilliant storyline. And I'm just really grateful.”
She said that giving birth is “a complete surprise” for her troubled character, who has gone back on drugs after Kevin found out about her one-night stand with Imran.
Sally said: "She had no inkling that she was pregnant."
Sally explained that although her character is six months pregnant, Abi didn’t realise.
She had briefly wondered if she was pregnant after the fling with lawyer Imran.
But she got her period, and after that “there weren’t any signs.”
Sally said: “It actually does take a while before Abi realises this is what's happening. She thinks she's just got a backache because she slept funny.
"But she recognises the contractions because she's had three children. But I think there's also an element of denial right up until the last point. It’s a complete surprise.”
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