Sydney woman Renee Young has given birth to twin girls born with a very rare medical condition called diprosopus.

The girls, named Hope and Faith, share a heart, a body, limbs and a skull, but they each have their own brain and a set of identical facial features.

Renee Young with Hope and Faith, who share a heart, a body, limbs and a skull, but each have their own brains and a set of identical facial features. Credit:Woman's Day

Ms Young and her partner Simon Howie, parents to seven other children, said the girls were doing well after being born on Thursday.

“They are breathing perfectly on their own and feeding,” Mr Howie told Woman's Day.