Tiny Kimberley Mueller weighed just over 10 ounces when she was born - making her the world's smallest surviving baby.
Her chances of living were rated at worse than 1,000-1 when she was born 15 weeks prematurely.
These incredible pictures published for the first time today show that Kimberley was about the size of a mobile phone at birth.
Now six months old, the miracle baby has been allowed home for the first time.
The size of a mobile phone: Kimberley Mueller weighed just over 10 ounces when she was born in Hanover, Germany - making her the world's smallest surviving baby
But Kimberley, who was just 10.2cm long, spent months on a life support system as doctors in Germany fought to save her.
The tiny mite was kept in an incubator for warmth and drip-fed, while a respirator help her breathe.
British birth experts said it was "incredible" that she had survived.
Dr Arvind Shah, consultant paediatrician at Great Ormond Street's Middlesex unit, said: "This is amazing - she must be a little fighter.
"Now we have more sophisticated equipment premature babies do have a better chance of living. But there are obviously huge health risks."
Kimberley's chances of living were rated at worse than 1,000-1 when she was born 15 weeks prematurely
Kimberley's mother Petra Mueller, from Hanover, said: "I was allowed to stroke her with my finger and I always spoke to her.
"It was the nicest thing when she would grip my finger in her tiny hands."