AT least six British mothers have frozen their eggs so their infertile daughters can use them to give birth to their half brothers or sisters.

The women want to give their daughters, who have medical conditions which prevent them from producing eggs of their own, the chance to become mothers.

The mother-to-daughter egg donation has been made possible by advances in freezing technology that enable eggs to be stored long enough for the child to use them.

Once the daughters reach adulthood, conventional in-vitro fertilisation (IVF) can then be used to allow their husbands to inseminate the eggs before implantation.

Some doctors say mothers should now be encouraged to freeze their eggs for their daughters’ use as soon as the offspring are diagnosed with conditions such as Turner syndrome, where sufferers lack ovaries.

The mothers only have a short period in which they can make the donation to their daughters because, by the time they reach the age of 40, their eggs are likely to be of too poor quality to store.

Dr Gillian Lockwood, medical director of Midland Fertility Services, where one mother has already frozen her eggs for her daughter and another is preparing to do the same, said: “The perfect egg donors for girls with Turner syndrome are their own mothers.”

The plans for women to give birth to their half siblings have, however, been criticised by some ethicists who fear that it could cause the daughters psychological problems, while the resulting children could be confused about their relationship to their mother and grandmother.

Josephine Quintavalle of Comment on Reproductive Ethics said: “The child could feel a crisis of identity trying to work out their relationship with relatives. The daughter’s husband may also feel an obligation to fertilise his mother-in-law’s eggs.” But fertility doctors say many women would prefer to have a child with a genetic link.

Professor Gedis Grudzinskas, a consultant gynaecologist at the Bridge Centre, in London, where one mother is preparing to store eggs for her daughter’s use, added: “This is a right and proper way to use this egg-freezing technology. It is a natural urge for women to want to become grandparents.”

Five women, whose daughters suffer from Turner syndrome or a metabolic condition, have frozen their eggs at Care Fertility, a chain of clinics across the Midlands and the north of England.

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