Eggs donated by young women could be used to repair the damaged eggs of older women, increasing the chances of successful fertilisation, Japanese researchers have revealed.
IVF often fails in older women because there are abnormalities in the outside of their eggs, known as cytoplasm, which surrounds the nucleus.
Researchers at St Mother Hospital in Kitakyushu, Japan, believe one way around the problem would be to implant the healthy nucleus - which contains most of the information to produce a baby - into the cytoplasm of a donor, usually a younger mother.
The researchers successfully did this in 31 eggs and of these seven formed 'early stage embryos' when injected with sperm in a test tube.
"If we could transfer these constructed new embryos, I believe the success rate would be high," the Telegraph quoted study's lead author Atsushi Tanaka, as telling New Scientist.
While the technique 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 kids.
Under the Human Fertilisation and Embryology Act, this kind of treatment - or any that involves genetically modifying an egg - remains illegal in Britain but the government has put in place a framework to relax the rules if and when science shows it can have positive impact on health.