Should women be paid for the time, discomfort and health risks involved in donating eggs for research? The world's largest group of stem-cell scientists is grappling with the question, and has now asked the public for its views.

Stem-cell researchers want eggs so they can work on somatic cell nuclear transfer, or 'therapeutic cloning'. They hope to derive embryonic stem cells matched to patients' DNA, by transferring the nucleus of one of the patient's cells into a human egg and developing it into an embryo from which cells can be derived. The technique has great medical potential — but researchers are far from achieving it, and the main limiting factor in the research is the availability of human eggs to practise on.

So far, scientists have relied on women already undergoing fertility treatment donating their extra eggs for research. But the supply is meagre. To help persuade them, several labs are increasingly offering financial rewards, such as cheaper fertility treatment. Others are starting to ask healthy women to donate — triggering a debate about how such women should be compensated.

Some ethicists argue that women should receive compensation for the discomfort and effort involved. Others are worried that this will create an undue incentive that will coerce women — especially poorer ones — into giving up their eggs. The fact that so little is known about the long-term health risks of the procedure further complicates the picture (see 'Health effects of egg donation may take decades to emerge', opposite).

Scientists in many parts of Europe, Asia, the Middle East and North America ask women to donate eggs for research, but they all treat the practice differently. Scientists at the North East England Stem Cell Institute announced on 27 July that they had got permission from the UK Human Fertilisation and Embryology Authority to pay part of the cost of in vitro fertilization treatments for women who donate eggs for research (see Nature 442, 498; 200610.1038/442498a).

But other European countries that accept egg donation for research, such as Sweden, prohibit payment for anything other than direct expenses. Japan bans egg donation altogether because of the risk of complications, whereas China, along with several other countries, does not specifically address the question.

In the United States, a National Academies panel recommended last year that women should be reimbursed only for direct expenses. This approach has been adopted by the California Institute for Regenerative Medicine, and by the state of Massachusetts, home of the Harvard Stem Cell Institute (see Nature doi:10.1038/news060605-6; 2006). Both institutes are asking healthy women to donate eggs for research. But even their policies differ — for instance, California law would allow paying the travel expenses of women who come from out-of-state to donate eggs, whereas it's not clear how Harvard will handle this question. “At the moment we're confining the search to this area,” says spokesman B. D. Colen.

Mixed blessing? Donating eggs is a time-consuming and uncomfortable business. Credit: H. MORGAN/SPL

Scientists want international guidelines so that they can share materials without worrying about how they were derived. So a task force of the International Society for Stem Cell Research (ISSCR) is considering the compensation question as part of a larger effort to draw up guidelines. The task force, made up of scientists, ethicists and lawyers from 14 countries, was convened last year after the revelation of scientific misconduct by South Korean stem-cell researcher Woo Suk Hwang: as well as faking evidence of 11 human embryonic stem-cell lines derived by therapeutic cloning, he lied about paying hundreds of women for eggs, and obtained eggs from his female subordinates.

On 30 June, the ISSCR task force released draft guidelines at its annual meeting in Toronto. The guidelines embrace most of the principles proposed by the National Academies last year. But they differ on the issue of egg donation. The task force leaves the door open for a more liberal policy on compensation by stating simply that stem-cell research projects should be reviewed by a local oversight body, which must ensure “there are no undue inducements or other undue influences for the provision of human materials”. What constitutes 'undue' is left to the local oversight bodies.

George Daley, a biologist at Harvard Medical School who chaired the task force, says that this is the best consensus the task force was able to achieve, because scientists and ethicists on the task force disagree so sharply about how egg donors should be treated (see 'Research volunteers or organ donors?).

The guidelines are seen as an important first step nonetheless, and are now open to public comment until 1 September, when the ISSCR will finalize the document.

“These are going to be seen as the rules set by scientists themselves, from the inside out,” says Kevin Eggan of the Harvard Stem Cell Institute. “It's very useful for scientists to show that they have thought about these issues.”