Researchers used eggs from young donors to repair damaged eggs of older women in order to increase their chances of fertilisation.
They have not yet used the eggs to produce babies, but they have injected them with sperm to produce an early stage embryo in the laboratory.While the move breathes new life into "old eggs" and could also remove genetic illnesses, it is likely to provoke an ethical storm as critics believe it could lead to hybrid or genetically modified children.
"If we could transfer these constructed new embryos, I believe the success rate would be high," Atsushi Tanaka, the lead author told the New Scientist.
IVF often fails in older women because there are abnormalities in the outside of their eggs, known as cytoplasm, which surrounds the nucleus.
The team at St Mother Hospital in Kitakyushu, Japan, believe one way around the problem would be too implant the healthy nucleus – which contains most of the information to produce a baby – into the cytoplasm of a donor, usually a younger mother.
So we would have a child with three biological parents.