Fertility experts last night welcomed draft guidelines from a government health watchdog suggesting couples should receive free infertility treatment on the NHS.

If given the go-ahead, the recommendation by the National Institute for Clinical Excellence (Nice) would end the current postcode lottery for IVF treatment. But it would cost at least £100m a year, according to one expert, and is likely to ignite a furious row over NHS funding.

The Shadow health secretary, Dr Liam Fox, yesterday attacked what he called the "haphazard" system for taking treatment policy decisions.

He said the move would be another signal to demoralised health workers that their primary role would be "to simply deliver a centrally determined agenda rather than to set priorities for their own locality".

Dr Sammy Lee, scientific consultant at the fertility unit of London's Homerton Hospital, said the idea was "wonderful" in principle, but warned that it could put further strain on an already stretched NHS budget.

He said: "If we're going to implement these recommendations, it's going to be very, very hard to do so without affecting funding elsewhere."

But Professor Ian Craft, from the London Fertility Centre, said: "We should have had this years and years ago. It was a sadness in many ways that we made the first test-tube twins 21 years ago within the NHS and that other people have had to pay for it since then, especially poor people who can't afford it."

At the moment the NHS treats around one in five couples free. The rest have to pay for private treatment.

These first draft guidelines from Nice, sent to health professionals, advise that women under 40 should be offered six cycles of treatment. The second round of consultation, which is open to public debate, will begin on 26 August, when a copy of the report will be published on Nice's website. A final decision will be made next February, which the NHS will be expected to follow.