The twins were born at University College Hospital, London
A woman has given birth to conjoined twins by Caesarean section.
Laura Williams, 18, from Shrewsbury, Shropshire, gave birth to the girls, named Faith and Hope, at University College Hospital, London.
They are believed to be joined from their breastbone to their navel but have separate hearts.
A family spokesman said things were looking "fairly positive" for the girls, who have since been moved to London's Great Ormond Street Hospital.
Conjoined twins are rare and figures range from one in about every 200,000 births to one in about 400,000 live births.
Mrs Williams and her husband Aled, from Anglesey, were advised by doctors to have their daughters aborted.
But she told the Mail on Sunday they had never considered it.
Her neighbour Tracey Parker, who has known the family for about four years, said: "I think fair play to her - she's giving the babies a chance.
"Laura was in bits to start off with but she's a good mum. She's got an older daughter and she's a good mum to her so I think she'll be good to these.
"I'm really pleased for her - I hope everything else goes alright."
Masha and Dasha Krivoshlyapova, from Russia, were the oldest known surviving conjoined twins. They died in April 2003 aged 53.
A team of surgeons in Birmingham carried out a successful operation in 2001 to separate Eman and Sanchia Mowatt, who were joined at the spine.