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"Rapunzel, Rapunzel, let down your hair" is the famous fairytale cry.

But real life moved from Grimm to gruesome for one 38-year-old woman in the US who had a giant 15cm hairball in her stomach.

She is one of only a handful of documented cases of "Rapunzel syndrome", which is caused by people plucking and eating their own hair.

Their once glorious locks build up in the digestive system where they can eventually have a devastating effect.

The woman, who has not been named, developed sudden vomiting and constipation. Meanwhile, her stomach swelled as it filled with liquids and gas.

She had gone off food for a year, lost 15lb in the previous eight months, and by the time she reached hospital, was unable to keep down any food.

Doctors in Arizona, writing in the BMJ Case Reports, initially gave her donor blood to tackle her anaemia.

But when they performed abdominal surgery they uncovered a 6inx4in (15cmx10cm) ball of densely packed hair in the stomach and then another 1.5inx1in (4cmx3cm) hairball in the small intestines.

The two elements of Rapunzel syndrome

Trichotillomania - the irresistible urge to pull out hair

Trichophagia - compulsively eating hair

The blockages were safely removed and the woman was given a diet high in protein to help her recover.

There have only been 88 other reported cases of Rapunzel syndrome.

In some the hair snakes all the way through the digestive system from stomach to large intestines.

Most cases are in childhood - with 40% of Rapunzels under the age of 10.

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