No 844, a 26-year-old aspiring banker of English descent with a 34in bust, straight brown hair and high cheekbones, whose brother is an air force intelligence officer, describes herself as “attractive, easygoing, humorous, intelligent, and well-rounded”. She says that she loves horseriding and Pretty Woman, the film starring Julia Roberts.

No 650, a married 32-year-old law student with two children who has blue eyes, brown hair and a 30in waist, plays the piano and enjoys rock climbing, claims that she is “energetic, happy, honest, intelligent, and thoughtful”. Her favourite animal: a salmon.

These women, and dozens of others listed on the website of the Genetics & IVF Institute, in Washington, are not exactly selling their bodies. They are offering their eggs for a fee.

The growing practice of egg donation in America is in the spotlight because of a new book by Debora Spar, of Harvard Business School, called The Baby Business.

“We are selling components of children,” Professor Spar said yesterday. “My whole argument is I would much rather we ’fess up to what we are doing and regulate it than push it under the carpet, as we have been doing with egg donation.”

As other countries tighten their rules, America’s loosely regulated market is becoming the world centre for egg donation. The Government’s Centres for Disease Control and Prevention has tracked a 40 per cent surge in the use of donor eggs, from 10,389 in 2000 to 14,323 in 2003, the latest year for which figures are available. Stem-cell research, still in its infancy, could add to demand for donor eggs.

Selling organs is illegal in America. But human eggs, like sperm, are not covered by the law. Nevertheless, fertility clinics insist that payments to donors are intended to compensate their time and effort rather than purchase the egg.

Donors have to undergo three weeks of hormone injections culminating in a short surgical procedure to remove about 15 eggs from their ovaries. The women who do so can suffer bleeding, allergic reactions or “hyperstimulation”, causing painful swelling. The long-term effects are unknown.

Fees range from $3,000 (£1,700) in the hinterland to $8,000 in New York. But prices skyrocket for special requests. A small advertisement posted in campus newspapers at Ivy League universities in 1999 offered $50,000 for the egg of a woman with top test scores who was at least 5ft 10in tall. More recently, a full-page advertisement in Stanford University’s student newspaper promised $100,000 to a Caucasian woman under 30 “with proven college-level athletic ability”.

The accepted price for sperm donation, by contrast, is a mere $75 per specimen. Professor Spar said that women were selling their eggs. “For sure, if you talk about $5,000 eggs you are talking about payment for time and inconvenience,” she said. “But if you are talking about $50,000 eggs you are clearly paying for physical attributes.”

A 22-year-old history and sociology student at the University of California, bound by a contractual pledge of anonymity, told The Times that she had contributed dozens of eggs in four cycles, which had already produced a set of twins and one other child.

“I am not the parent. I just give my DNA to them. There are so many guys out there who do it all the time,” she explained, comparing the practice to sperm donation. “That is how I try to describe it when people think it’s weird that I have done it. It’s a double-standard country.”

She was required to fill out a 36-page form giving a biography and medical history, and submit a photograph.

“I automatically assume they are choosing me because I look like the intended mother,” she said. “If I were in their position, I would be looking for someone with the same physical traits.”

Before the deal goes through, however, the would-be parents must explain to her exactly why they want her eggs. Explanations have included infertility due to cancer. She has not told her own parents. Her egg broker in Mission Viejo, California, pays a base fee of $6,250 per donation with $500 extra if a previous donation has resulted in a pregnancy.

“Most of them are college students because they need the money for school,” the broker said, asking not to reveal her name. “For them, it’s like doing something good — and getting paid for it.”

Donors get a $250 bonus if they have good grades at university. “We do not compensate more for having blonde hair and blue eyes,” the broker said. “We do compensate more for good scores.”

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