The demand for women’s eggs for research could soar alarmingly following news of a cloning technique that uses human oocytes to reprogram somatic cells to a state of pluripotency (S. Noggle et al. Nature 478, 70–75; 2011).

The mean number of eggs given by each woman during the study was 16.9, with one donating 26 eggs. This is more than many fertility doctors would consider optimal and increases the risk of ovarian hyperstimulation syndrome. The researchers do not say that they halted hormone treatment in cases of over-response, although they did stop it in under-responsive women.

Noggle et al. rightly anticipated concerns that payment for eggs could encourage financially disadvantaged women to take risks they might otherwise avoid. But US$8,000, the amount paid by Noggle and colleagues, would be a temptation even to the well-off in these difficult economic times.

Some argue that women should evaluate for themselves the risks and benefits of providing eggs for research. But informed consent depends on provision of accurate information. Even after years of egg harvesting for fertility treatment, the risks to women —...