Overweight women and those who smoke should be refused IVF treatment, according to many experts surveyed.

More than 40 per cent believed access to IVF should be conditional on lifestyle - so that, for instance, smokers were disqualified.

A large proportion of the experts said they should change their habits before they are given care.

They outnumbered the 28.8 per cent who agreed with the statement "access to IVF should be offered to all regardless of lifestyle".

And many experts surveyed also believe too many new fertility treatments are being offered to patients without sufficient proof that they work.

Almost half the doctors, nurses and scientists taking part in the survey agreed that new procedures are being brought in too hastily.

Some 85 per cent of those questioned wanted to see more clinical trials to test the effectiveness of novel In-Vitro Fertilisation (IVF) techniques.

The survey of 186 mostly British experts was carried out to mark the 30th birthday of the first IVF baby, Louise Brown.

Louise was born at Oldham and District General Hospital in Greater Manchester on July 25, 1978, ushering in a fertility revolution which continues to this day.

The survey was conducted by the British Fertility Society (BFS) in conjunction with the Science Media Centre in London and the European Society of Human Reproduction and Embryology (Eshre).

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