Once we have a better understanding of the definition of human life, then we can discuss stem cell research rationally rather than emotionally. Here I want to draw the parallel between terminally ill patients and the frozen embryos left over from fertility clinics, when there is no practical hope for a functioning human life to result from continuing artificial life support.

The definition derived above is a definition that is consistent at both extremes of human life, one before a conscious functioning individual human being has developed and one after a conscious functioning individual human being has ceased to exist. Both cases involve certain amounts of cell material that is still living, cases where families may need to make decisions whether or not to continue artificial life support systems. Certainly the legal and ethical basis for this type of decision has been developed for the termination of life, when tissue and organs can be transplanted for the benefit of human life. This same ethical and legal basis should apply at the other extreme, as should the abilities of families to apply their particular beliefs to the choices they make.

Fertility Clinics and Stem Cell Research

From Freezing of human sperm, oocytes and embryos:
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Most typically, embryos are frozen 1, 3 or 5 days after the sperm and egg were put together. Freezing is a stressful process for an embryo, and only embryos that are growing well in the laboratory will tolerate the freezing procedure.
Technically at this age these are blastula rather than embryos. Many do not survive the freezing process, but enough are processed that there is usually a large surplus. From In-vitro Fertilization (IVF) Clinics:
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The procedure involves:
  • Giving special medication to the woman that results in the development, growth, and maturation of eggs in a woman's ovaries.
  • Extracting perhaps 24 mature mature ova (aka oocytes) from the woman's ovaries.
  • Fertilizing the ova with sperm, typically from her husband or an anonymous donor.
  • Placing the embryos in a special incubator which encourages their growth.
  • Selecting two to four healthy-looking embryos and implanting them in the woman's uterus.
  • Disposing of the remaining 20 or so surplus embryos in some manner.
The disposal of almost all of the embryos results, or will result, in their death.
The question becomes what should be done with these surplus embryos once they are no longer needed by the families involved.

The implications for stem cell research derive from the legal definition of death used above and the choices faced by the family in regards to sustaining life support systems. Looking to the application of the legal death definition for guidance, we see that families have a choice when they decide to terminate life support of a relative on whether to donate organs for other people or to donate the body to research.

There has also been a survey of fertility clinic patients, Forbes article: Fertility Patients Favor Donating Unused Embryos for Research:
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About half of patients being treated at U.S. fertility clinics say they'd be somewhat or very likely to donate their unused embryos for stem cell research, a new survey finds.

The findings, released early Wednesday by the journal Science, mean that up to 10 times as many embryos would be available for research than previously estimated, should U.S. legislators ever permit their wider use.

That number increased to 60 percent when the question referred specifically to stem cell research and research aimed at developing treatments for human disease or infertility.

Other options, such as having the embryos destroyed or donating them to another infertile couple, seemed less attractive.
The Science article: Willingness to Donate Frozen Embryos for Stem Cell Research
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Moral concerns about the primary source of stem cells, human embryos, have prompted one of the most contentious public debates in the history of biomedical science. Following the announcement of a restriction of U.S. federal funding to research with about 20 cell lines isolated from embryos before August 2001 (1) and, more recently, a presidential veto upholding this restriction (2), there has been a clear message from the scientific community that the eligible lines are not only inadequate in number but also unsafe for translational research. There is also mounting evidence that American scientists are losing ground to other countries with less restrictive policies (3). Further, surveys of the American public indicate that there is widespread support for embryonic stem cell (ES cell) research that cuts across political, religious, and socioeconomic lines, with approval estimated at 66% of the public overall (4).

A total of 1244 patients returned the survey, for a 60% response rate overall [63% for women, 51% for nongestating partners (male or female)]; surveys were sent to only one member of a couple. We made clear at the outset that the embryo is destroyed if used for research.

Of the 1020 respondents who reported that they have embryos currently stored, 495 (49%) indicated that they were somewhat or very likely to donate their embryos for research purposes. These 495 individuals controlled the disposition of from 2000 to 3050 embryos.

Respondents to the survey expressed even greater willingness to donate embryos to research when certain characteristics of the research were specified. In particular, the percentage reporting that they would be somewhat or very likely to donate increased from 49% for medical research (in general) to 60% for research in which stem cells are derived.
The preferred alternative to keeping embryos forever, or disposing of them, therefore, is for them to be used for medical research aimed at improving human life.

Ethically there should be no question that allowing the use of cellular material from an embryo is a question that should be left to the family to decide, as this is the same as the situation at the end of life when there is no practical hope for a functioning human life to result from continuing artificial life support.

There is no ethical question on the use of adult stem cells for research, and with the ethical question of legal life being resolved, there can be no ethical question on the use of embryonic stem cell research: in both cases the materials are donated to research by the "appropriate surrogates" - the families involved.

Conclusion

Using the definition of human life proposed here we can provide the same ethical treatment regarding the question of life and death for frozen embryos as we currently use for terminal patients, and allow families to decide what is best for their families.

This allows us to evaluate whether using surplus embryos from fertility clinics for stem cell research is ethical based on the existing criteria: the same conditions apply, that families are faced with the decision to
  • continue artificial life support with no practical hope for a functioning human life to result from continuing such support,
  • halting life support and letting the remaining cells, tissues, etc. that are being kept alive artificially to expire naturally, or
  • donating material (cells, tissues, etc) for medical research or to use for transplants.

From the survey above we see that, just as we see with the end of life, different families will make different decisions.

Letting the families concerned make the decisions on what to do with the surplus embryos meets the needs for a plurality of beliefs to be accommodated within our society, in the same way that it is for terminally ill patients, and it meets the same ethical demands of each of those families.

Enjoy.
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Note: my time is limited, so I only choose threads of particular interest to me and I cannot guarantee a reply to all responses (particularly if they do not discuss the issue/s), and I expect other people to do the same. Thank you for your consideration.[/color]