BOSTON – It’s no surprise that the debate about cloning research has turned a degree or two from focusing on the moral status of the egg to the moral status of the egg donor.

Up to now, we’ve treated eggs as if they were disembodied commodities. You go to a biology supermarket, pick up a dozen extra-large and trundle them off to the research lab.

But so far there’s only one source for the hundreds of eggs needed for the stem cell research that uses cloned embryos: women. Egg donors are likely to undergo the same treatment as women do for in vitro fertilization. That means a full regimen of medications followed by surgery to extract the eggs.

Egg donation is, to put it delicately, more labor intensive than sperm donation. It entails more hormones and fewer copies of Playboy.

The history of women who have undergone IVF over two decades suggests that it’s a pretty safe procedure. But there may be short-term risks from overstimulating the ovaries, and there may be long-term risks as well from hormones. So far, these too seem pretty low, but history has left us properly wary.

This wariness has led a number of activists in the women’s health community to raise a cautionary flag. Judy Norsigian, known to generations raised on her co-authored “Our Bodies, Ourselves,” has written that we should “postpone embryo cloning research with human eggs until better data make true informed consent possible.”

She and others raised their concerns in Massachusetts, where the Legislature just approved a bill promoting stem cell research. Meanwhile in California, Deborah Ortiz, a state senator who supported Proposition 71 for state-funded research, has asked for a three-year moratorium on multiple-egg harvesting.

These arguments have been eagerly scooped up by the opponents of stem cell research, especially those folks who believe that an embryo in a dish is the moral equivalent of an MS patient in a wheelchair. They have been dubbed a holy or unholy alliance depending on your point of view.

Well, what are we to make of it? About 100,000 women a year have their eggs harvested. Of these, 90 percent are going through IVF to become pregnant. The rest are donating eggs that will be implanted in other women. These donors include women moved by altruism and women wooed by ads offering money for DNA with high SAT scores. How do we compare them with women willing to donate eggs for research?

Ironically, there are stricter standards governing egg donors in a human research project than in a fertility clinic. Human research is subject to an independent board of review and long-term follow-up. We may never know what will happen in 20 years, but human research requires a lengthy and elaborate informed consent procedure.

In California and in Britain, guidelines have ruled out paying for eggs and put a ceiling on reimbursement. It is largely agreed that no individual woman should go through more than one or two donor cycles.

Of course, Ortiz and others say scientists can harvest eggs for stem cells through “natural cycling.” That would harvest one egg per month. But it’s not at all clear that using more women to collect the same number of eggs would entail less risk.

Finally, this odd set of bedfellows is raising the same question: Can women make these decisions themselves?

We allow men and women to donate kidneys or portions of their liver. People participate in all sorts of research. Is there something inherently different between allowing a woman to take the risk of childbirth and allowing her to take the much smaller risk of donating eggs that may eventually cure her child’s diabetes? I don’t think so.

It’s likely that the donors will be those who have some first-hand family experience. That’s been the finding so far of the Bedford Stem Cell Research Foundation, where director Ann Kiessling says that “We are contacted regularly by people who have a serious illness in their family and would like to help.”

Bioethicist Alta Charo puts it bluntly: “I volunteer. My motivation is entirely about a friend with Lou Gehrig’s disease. I never in my life dreamed nature could be so cruel, and I would do almost anything to prevent that from happening to someone else.”

None of these moral arguments would matter if cloning research didn’t hold such enormous promise to unlock the secrets of genetic diseases. This is a promise that rests for now on egg donations. It’s not a step to be taken lightly. It’s not trivial. The women who volunteer should indeed be treated with caution … and also with gratitude.