A lesbian couple are applying for fertility treatment in the hope of having "a baby that has truly come from both of us".
Vicky Hill, 22, plans to become the genetic mother by donating an egg to her lover, Hayley Marlow, 29, who will have it fertilised and implanted in her womb to become the birth mother.
The procedure will cost thousands of pounds and carries extra risks but the couple say they will do anything to share a baby.
Normally one member of a lesbian couple wanting a family will be inseminated with donor sperm - a simpler and safer technique.
The couple, from Banbury, Oxfordshire, have already met Ms Hill's GP to discuss their plans and request a referral to the John Radcliffe Hospital in Oxford.
A spokesman for the Human Fertilisation and Embryology Authority said that legally the baby would belong to the mother who gave birth and not the one who supplied the egg. "The only way they could become equal parents would be if the mother who gave birth were to renounce her claim to the baby and then they could adopt it," he said.
He said doctors would have to ensure that the physical risks of the procedure were outweighed by the potential benefits of their joint involvement.
The couple have been together for just over a year. Ms Marlow has a five-year-old daughter.