Well, I found this, which is interesting:
Guinness Book of World Records
World's Most Premature Baby
"James Elgin Gill was born to Brenda and James Gill on May 20, 1987, in Ottawa, Ontario, Canada. He was 128 days premature, and weighed just 624 g (1 lb 6oz). James' parents were told he had no chance of survival. Much of his body was still developing, including his skin, hands, ears, and feet. James' eyes were still fused shut."
Then I found this:
"Doctors at a hospital here have delivered what is claimed to be one of the world's smallest babies - at 524 grammes just half the weight of a bag of sugar. In a tricky operation, surgeons removed the mother's womb containing the baby in order to save the life of the Iraqi woman who was suffering from cancer of the stomach.
The infant had spent just 21 weeks and three days in in his mother's womb. Doctors fed him his mother's milk through a tube from the moment he was removed. The operation took place at Abu Dhabi's Al Mafraq Hospital.
Professor Mohammed Reda Sadaqetian, consultant and head of the paediatric department for premature children, said, "This is considered the smallest baby in the world, taking into account the number of weeks spent in his mother's womb.
"When he was was born, he was 524 grammes. Before this, the smallest child who survived was 329 grammes, but he was born after 28 weeks. "From the day of his birth he started drinking his mother's milk through a tube. Then from the second day, he started taking nutrition through the arteries and now his growth is continuing naturally without any complications. His eyes remained closed until recently but we managed to open them."
The baby's weight has reached 620 grammes. The infant had suffering from bleeding in the brain, which has stopped. Because of the bleeding, the baby may be only 50 per cent normal. "We will monitor his condition for six months until we identify if this percentage will decrease or increase."
Sadaqetian said that the child was prematurely delivered to save the life of the mother. "The mother was suffering from stomach cancer and we had to save her by taking out part of her intestine, and it was necessary to remove the mother's womb with the child in it. The mother's condition is very stable now."
He said it was remarkable that the baby had survived despite being in his mother's womb for only 21 weeks and three days. It was very rare for such a premature baby to survive. The 2001 Guinness Book of Records lists the world's most premature baby as James Gill of Ontario, Canada, who was 624 grammes when born 128 days premature in 1987."
So there you go. I can't vouch for the second source- I'd never heard of it.
As someone mentioned, if this woman knew of such a baby, it surely would have been a record or at least had some news coverage.