The removal of anonymity from sperm and egg donors has provoked a crisis in fertility treatment that is denying couples the chance to try for a baby.

Infertility therapy with donated sperm has collapsed to the lowest levels since records began, according to the first official figures, seen by The Times, since the Government banned anonymous donation in 2005.

The number of women treated with donated sperm fell by about 20 per cent, from 2,727 in 2005 to 2,107 in 2006, the first full year after the change. The number of donor insemination treatment cycles fell by 30 per cent over the same period.

Egg donation is also in serious decline: the number of treatments using “shared” eggs, offered by women in return for a discount on IVF, fell by 40 per cent between 2004 and 2006.

The figures demolish claims by ministers and the Human Fertilisation and Embryology Authority (HFEA) that sperm donation has improved since anonymity was ended. Last year Shirley Harrison, then the chairwom-an of the authority, said it was “a myth” that there had been problems.

Although the number of sperm donors has risen slightly, many will be friends and relatives who donate for a couple’s exclusive use. Fewer donors are contributing to sperm banks, from which the donation can be used by up to ten women. The result is that although more donors have been registered the shortage of sperm is becoming more acute.

The law, which took effect on April 1, 2005, gives donor-conceived children the right to trace their biological parents when they reach 18. The Government said that children’s rights to discover their genetic origins outweighed donors’ right to privacy. Many doctors, however, predicted that this would worsen an existing shortage of sperm and eggs, because donors would worry about being approached later in life.

Most clinics now have waiting lists of at least two years for sperm, and a similar trend is affecting egg donation. Although altruistic donation, which is usually done by sisters or friends for a patient’s exclusive use, has remained static, the egg-sharing schemes that help couples without a known donor are in trouble. Shared eggs were used in only 680 fertility procedures in 2006, compared with 1,142 in 2004, the last year before the law was changed.

MPs and fertility doctors say the figures show that the end of anonymity has denied treatment to thousands of infertile men and women.

Evan Harris, the Liberal Democrat science spokesman, said: “The Government and the HFEA have been saying everything is fine, but it isn’t. There was no good reason for removing anonymity, which has led to a catastrophic drop in the number of patients treated by donor insemination.

“There was always a huge risk that this would happen, diminishing the capacity of both the NHS and private clinics to treat infertility. There are probably now thousands of untreated couples who may be forced abroad, or into the unregulated sector.”

Gillian Lockwood, medical director of Midland Fertility Services, said her clinic had performed 83 treatment cycles with donated sperm last year, compared with 221 in 2004.

“The picture at the coal face is bleak,” she said. “A significant number of patients are now being turned into fertility tourists, who are going abroad for donor treatment.”

A spokesman for the Department of Health confirmed that the number of egg donors had fallen. “We are therefore preparing a regional egg donor recruitment campaign which will be launched in stages from July,” he said.

A spokeswoman for the HFEA said: “The HFEA supports the efforts of clinics actively recruiting donors.”

Pip Morris, of the National Gamete Donation Trust, said: “We’ve never had enough donors. It’s nothing to do with the law, it’s a lack of awareness.”

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