Simon Cowell courted controversy last night when he put a contestant through to the next stage of The X Factor before changing his mind because she was pregnant.

Katie Boothand, 24, from Skegness, was five-and-a-half-months pregnant when she auditioned for the talent show in Sheffield, leaving open the possibility that she could give birth during the series.

She lives with her fiance, who came to the audition for support, in a cramped one-bedroom flat, and said winning The X Factor would secure a future for her family.

Prior to her audition, producer and judge Cowell told Boothand: "I'm working out the dates here, not great dates are they?"

The aspiring singer joked that she could be the first woman to have a child born on X Factor, before singing the Faith Hill song There You'll Be.

Following her performance, Cowell said: "You're five and a half months pregnant so you'd be having a baby right in the middle of the live shows."

He said Boothand suffered from a bad lisp but that she had a good singing voice and was "very likeable".

Fellow judge Sharon Osbourne said Boothand "sang very, very well indeed" but asked whether she could cope with the pressure of being pregnant during the show.

With Dannii Minogue the only one to disapprove, the 24-year-old was thrilled to learn she had got through to the next stage.

But after she left the room, the judges had doubts.

Cowell said: "A part of me thinks we shouldn't have just done that because she's five-and-a-half-months pregnant. That should have been a 'no'. It doesn't feel right, I'm almost inclined to change my mind now."

Louis Walsh agreed, and Minogue said: "I've got nothing against pregnant women but you can't be singing on live TV and giving birth at the same time."

Cowell then left the audition room to break the news to Boothand: "I think we've made a mistake.

"I absolutely think this is the wrong decision and I know it's horrible to be given a 'yes' but I want to be honest with you, I don't feel right about this.

"I'm thinking about you and the kid and everything and I think this is absolutely the wrong thing to do."

A devastated Boothand said: "He knew I was carrying a baby. He knew I was five and a half months pregnant. He knew the complications.

"At the end of the day, that's my decision and if I want to enter this competition and go all the way to the end, I will do that."

As she stormed out of the building, her fiancé threatened to smash the cameras filming their exit.

Cowell later defended his decision: "This is a girl who would have given birth to her baby in the middle of The X Factor finals.

"The stress she would have been under would have been unspeakable. You cannot put a competition like this or your ambition over the fact you're about to have a baby. It is crazy."

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