The regulator recommends three free IVF cycles on the NHS
Thousands of infertile couples are missing out on the recommended level of IVF on the NHS because health trusts are refusing to fund it.
Only nine out of 151 English health trusts offer three IVF cycles, despite guidelines issued four years ago.
Campaigners said many are using unfair criteria to deny couples treatment.
The Department of Health said more trusts now paid for at least one IVF cycle, and it was working to implement the guidance fully.
Average success rates per cycle of IVF are approximately 25% , falling sharply after the age of 35.
The National Institute for Health and Clinical Excellence issued the guideline in February 2004, and then Health Secretary John Reid said that he expected all trusts to be offering at least one cycle by 2005.
However, NICE acknowledged that the move to three cycles would take more time, and no target date for implementation was given by the government.
The latest figures were released by the Department of Health, and revealed that four trusts were still offering no IVF treatment at all, and 94% were not providing the full three cycles.
The majority of IVF cycles in the UK are still carried out in the private sector, at a cost of approximately £2,000 each.
Susan Seenan, from the charity Infertility Network UK, said that many of those offering one or more IVF cycles were ignoring the guidance in other ways to deny patients access.
Some were setting age limits, she said, with a few refusing IVF until a woman was over the age of 35.
"This means she has a much smaller chance of becoming pregnant," she said.
Other refused treatment to couples with existing children, even those from previous relationships.
Ms Seenan said: "It's all about rationing treatment to save money.
Unfortunately, infertility is still not seen by many people as a clinical need. "It has been four years, which is quite long enough to implement the guidance."
She said that Infertility Network was working with the Department of Health to try to speed this up, but a government spokesman said that the "local NHS" was ultimately responsible for decisions on IVF provision.
"We recognise that there are local variations in the provision of IVF and that this does cause distress to many childless couples who feel that they are not getting the treatment they need."
"We are working closely with Trusts to establish their progress towards meeting NICE recommendations around the provision of IVF services." It said that the number offering no IVF treatment had fallen since the introduction of the guideline