Colin McDougall on baby Zoe

Zoe McDougall weighed just 15oz and measured 30cm when she was born prematurely by Caesarian section in Simpson's Memorial Maternity Hospital, Edinburgh.

After four months of battling to put on weight she now weighs a healthy 6lbs 2oz, and has been allowed to head home with parents Joanne, 26 and Colin 28, from Addiewell, West Lothian.

By the time she is two or three, she will be at the same stage of development as other children her age.

Fitting in the palm of one hand

There are no official records of the country's smallest babies.

But a hospital spokeswoman said: "Certainly the baby was very, very small. We are absolutely delighted she has survived."

Hospital consultant, Dr Ben Stenson, said: "She was the smallest baby we had ever looked after. We are absolutely thrilled that Zoe is doing so well.

"A baby as small as she is has to overcome an awful lot and has to have a great deal of strength and courage, as do the parents."

Her father Colin said: "She was so small she fitted right inside the palm of one hand."

It was eight to 10 weeks before her parents could hold her and then only for a couple of minutes at a time.

"It was frightening but good at the same time," said Colin.

"She was so tiny we were really scared, but it was good because she belonged to us."

Small babies

The smallest baby ever to have survived is thought to be Ambika Marula who was born earlier this year in the United States.

She was three months premature and weighed just over 11oz when doctors delivered her at Shady Grove Advent Hospital near Washington DC.