Paul Rainsbury talks about the ethical issues

The couple, from Enfield, north London, are in discussions about the practicality and implications of such a move with leading gynaecologist Paul Rainsbury, who works at the private Bupa Roding Hospital in Ilford, Essex, but also runs a private IVF clinic.

The woman, 32, and her husband, 34, a merchant banker, are both said to be dedicated to their work and unwilling to risk compromising their careers, while at the same time conscious of the greater chance of complication associated with attempting to get pregnant later in life.

More mature

Paul Rainsbury: 'Ethical barriers are being shifted'

Mr Rainsbury said the technique was allowed by the Human Fertilisation and Embryology Authority, which regulates IVF in the UK.

He said freezing embryos was a common practice for couples undergoing IVF, the only difference was that this time it might be done for non-medical reasons.

Mr Rainsbury said: "The couple felt they would be more mature in four or five years time as parents; they would have more life experience and they would be more financially secure.

"From an ethical point of view, it is shifting the barriers slightly, but it is no more fraught with difficulties than other complex treatments like surrocacy, like egg donation, which are all practised legally in this country.

"Some people feel there are still many children born at the wrong time to couples who are unable to support them in the way they wish to support them. Maybe they are being selfish, this couple, but if it means this child is eventually born into a happy, loving relationship, why should that bother society?"

Mr Rainsbury said that in the event of the couple splitting up before the woman fell pregnant, it would be for the clinic to decide what to do with the embryo. It could be destroyed, used for research, or given to one of the "parents."

'Fundamentally wrong'

Mr Rainsbury attracted controversy last year for charging couples to choose the sex of their baby at a clinic in Italy.

IVF technology: is it wrong?

Dr Adrian Rogers, a former GP and director of the Conservative Family Institute, said the advantage of freezing an embryo was that the use of a younger sperm and egg minimised the risk of disability or genetic mutation.

But he said freezing embryos was fundamentally wrong.

Dr Rogers said: "This is a matter of human rights. Once a new individual has been created it has a right to be born and not stored in suspended animation.