A couple have persuaded a private IVF clinic to operate in breach of its licence by storing their fertilised embryos past the time they should have been destroyed.

By law, unused embryos created for surrogacy must be destroyed after five years have elapsed. The deadline has passed for Martin Hymers and Michelle Hickman, who have been unable to find a surrogate mother to carry their six embryos, despite investing £10,000 in the search.

In desperation, the couple, from Heaton Chapel, Greater Manchester, are now applying to the Human Fertilisation and Embryology Authority (HFEA) to transfer the embryos abroad. In the meantime, their clinic, Manchester Fertility Services, has agreed to store them - even though the embryos should have been destroyed on Monday. It is illegal to advertise for a surrogate mother in the UK but a fertility clinic in Belgium is considering taking the embryos.

The saga began when Ms Hickman was pregnant with their son Robert, now six. Doctors predicted he would be a big baby so she opted for an elective Caesarean. There were complications during the operation and, despite her protestations, Ms Hickman's uterus was removed. The couple underwent IVF treatment to store embryos.

Friends volunteered to act as surrogates but were unsuitable on health grounds, and now the five-year limit has elapsed - with a second batch of seven embryos due to be destroyed next year.

The couple claim the law is unfair, as embryos created for any fertility problems other than a missing womb can be kept for 10 years. Both the medical profession and HFEA agree the discrepancy in the law is unfair - but any change will be delayed until after the Government's review of the HFEA Act, in 2008. That will be too late to save the Manchester couple's embryos.

Dr Brian Lieberman, of Manchester Fertility Services, said the current law was "manifestly wrong" and "illogical". An HFEA spokesman said the authority had raised the issue with the Government.