The success of the operation means the lives of several babies in need of small bowel transplants could be saved.

It involved blowing up the baby's gut so that it could take the liver and small bowel of an older child.

Jack Glass was born prematurely with just 12% of his bowel with a rare condition called necrotising enterocolitis.

He was fed intravenously, but, at such a young age, this harmed his liver.

Because of a lack of suitable donors his age, doctors at Birmingham Children's Hospital decided that the only way to save his life was to perform the pioneering operation.

It involved surgeon Jean de Ville de Goyet inserting a small tissue expanding device like a deflated balloon into a small cut in Jack's side and inflating it with sterilised water every two weeks.

After two months, his bowel was 25% larger so that it could fit the small bowel of a donor who was around 10 years old.

Jack also needed a liver transplant. The liver was trimmed to fit into him. The organ can regenerate itself.

The tissue expander is normally used on burns victims to grow new tissue.

Expanded bowel

Jack, who has a twin sister, was 9.6kg at the time of the operation. The donor weighed 30kg.

Jack's original gut measured 12 inches. His replacement is seven feet long.

He was discharged from the hospital on Monday for the first time in his life and will return to his home in Glasgow.

His mother Carrie said she was "overjoyed" at being able to take her son home.

"For the first time, Jack is now able to do all the things normal babies do, going for walks, playing with his toys, watching videos and enjoying food.

"I would like to thank the donor family for giving us that opportunity."

Consultant hepatologist Dr Sue Beath said: "We are delighted that the tissue expander has proved to be effective and plan to use it again for our smaller patients who require liver and bowel transplants.

"Finding suitable donors for babies is very difficult. This procedure opens up the possible donor field tremendously."

Doctors estimate that two out of three babies who need urgent small bowel transplants die for want of a suitable donor.

Only a small number of infants need a small bowel transplant every year.

The operation is fairly new with just over 300 transplants having been carried out worldwide since 1991.

Birmingham Children's Hospital is the only national centre for this operation in children.

Some are given transplants using trimmed down organs, but these are not very successful.

A spokeswoman for the Children's Liver Disease Foundation which supports some families whose children have developed bowel and liver problems said: "It appears the success of the operation is related to the amount of bowel which is transplanted."

A spokeswoman said: "This operation could help save a lot more lives."