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Expecting: The brand new extended trailer for Breaking Dawn reveals Kristen Stewart as Bella with her baby bump
Previously unseen footage of a pregnant and dying Bella Swan has finally been revealed to Twilight fans.
An extended theatrical trailer for Breaking Dawn: Part 1 was released today with the scenes of sickly, frail Bella (Kristen Stewart) fighting for her life and her baby.
The dramatic two and a half minute trailer from the movie, the fourth in the series based on the books by Stephenie Meyer, opens with Bella trying to calm her nerves before walking down the aisle.
Dying: The newlywed is shown for the first time in her frail state
Clutching her father Charlie's arm, she says, 'Just don't let me fall Dad.'
She says her vows with Edward (Robert Pattinson) in a breathtaking setting, with the Cullen family proudly looking on.
Bella's happiness is interrupted as a dishevelled and distraught Jacob arrives to say his final goodbye before Bella leaves as a married woman - soon to be transformed into a vampire.
Heartbreak: Bella is told that her heart will give out before she can deliver her baby
The end? In the trailer, fans see Bella collapse with her husband rushing to catch her
The best friends are seen dancing alone in the dark as heartbroken Jacob tells her: 'This is how I'll remember you - pink cheeks, heartbeat. You'd think I'd be used to telling you goodbye by now.'
A brief glimpse of the newlyweds' blissful honeymoon and wedding night is shown.
Edward's strength breaks the bed frame in the throes of passion; he tells his wife the next morning that 'last night was the best night of my existence'.
Before baby: Earlier, Bella's nerves show as she prepares to walk down the aisle on her wedding day
Breathtaking: The scene is set for the romantic nuptials
Happiest day: Edward can't hide his joy as he watches his bride walk down the aisle
But their honeymoon period is short lived when they discover Bella is pregnant with a half human, half vampire baby.
Bella's health rapidly deteriorates and she is shown looking deathly pale and thin as Dr Cullen informs her that her heart will give out before she can deliver her child.
As Bella fights to protect her baby and live long enough to deliver it healthily, the wolves hear of the unborn child and decide it is a threat.
Family united: The Cullens proudly watch as Edward and Bella say their vows
One last dance: A distraught Jacob arrives at the wedding to say his goodbyes to Bella
Paradise: Edward sweeps Bella away to their own private island for their honeymoon
Pack leader Sam is shown telling them: 'We don't know what they've bred, we have to protect the tribe before it's too late.'
Jacob defects to warn the Cullens that a war is coming for them. 'Bella will be slaughtered,' he tells them.
The nail-biting preview ends with Bella collapsing, and Edward and Jacob rushing to save her life and deliver the baby.
Bliss: Bella awakes after her wedding night in a cloud of feathers
Distraught: Bella's father Charlie is told his daughter is dying
War: With Bella's unborn child an unknown threat, the wolves decide she must be killed in order to protect their tribe