the first time, stem cell scientists have
convened a meeting to discuss what is and is not known about
risks to women who undergo egg extraction. The September 28 event,
"Assessing the Medical Risks of Human Oocyte Donation for Stem
Cell Research," was sponsored by the California stem cell research
program and organized by the Institute of Medicine.
used data from the assisted reproduction field to inform stem cell
researchers who plan to perform research cloning. Taken together,
they made clear that further study is needed to assess the long-term
health impacts of egg retrieval, and that managing short-term risks
depends on careful monitoring of women while they are taking the
hormonal drugs that the procedure entails.
was general agreement that the most troubling short-term health
risk of egg retrieval, ovarian hyperstimulation syndrome, is better
understood than the long-term effects. These are less well defined
due both to the difficulty of conducting such studies, and to the
fact that egg retrieval has been performed on a wide scale for only
twenty years. For example, existing data cannot rule out a relationship
between the procedure and several types of cancer, especially those
that would be showing up only after this lapse of time.
The risk picture
is further complicated by the differences between providing eggs
for reproduction and doing so for research. Women in these two settings
are likely to have different characteristics, including age and
There are also
significant differences on the benefit side that affect evaluation
of "risk tolerance." Among women who undergo egg retrieval
for fertility purposes, the vast majority do so in order to have
their own baby—a situation that offers a very different kind
of benefit than providing eggs for another woman, which in turn
differs from providing eggs for research.
The data suggest
that negative outcomes, particularly short-term effects, are related
both to characteristics of the women and to the care with which
medical personnel monitor women during the drug regimen. Adverse
effects should be greatly reduced if at-risk women are prohibited
from providing eggs, and if egg providers are closely monitored.
Whether or not these practices are followed will depend on the development
and implementation of effective oversight.
Watch a video
webcast of the entire event.