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The Davis dilemma: how to prevent battles over frozen preembryos.

Cryopreservation of preembryos, or the freezing of fertilized human eggs, is a procedure increasingly used by infertile couples to improve the odds of success of advanced reproductive technologies. As a consequence, divorcing couples are finding themselves in dispute over the disposition of frozen preembryos that have not been implanted. Courts have been called on to decide to whom the frozen preembryos should be awarded, but the law is unclear whether frozen preembryos should be treated as marital property, as children, or as something else. The author analyzes various arguments concerning the appropriate legal status of frozen preembryos, and suggests a new rule to settle such disputes.

Beginning of Human Life↗

Conundrums with penumbras: the right to privacy encompasses non-gamete providers who create preembryos with the intent to become parents.

To date, five state high courts have resolved disputes over frozen preembryos. These disputes arose during divorce proceedings between couples who had previously used assisted reproduction and cryopreserved excess preembryos. In each case, one spouse wished to have the preembryos destroyed, while the other wanted to be able to use or donate them in the future. The parties in these cases invoked the constitutional right to privacy to argue for dispositional control over the preembryos; two of the five cases were resolved by relying on this right. The constitutional right to privacy protects intimate decisions involving procreation, marriage, and family life. However, when couples use donated sperm or ova to create preembryos, a unique circumstance arises: one spouse--the gamete provider--is genetically related to the preembryos and the other is not. If courts resolve frozen preembryo disputes that involve non-gamete providers based on the constitutional right to privacy, they should find that the constitutional right to privacy encompasses the interests of both gamete and non-gamete providers. Individuals who create preembryos with the intent to become a parent have made an intimate decision involving procreation, marriage, and family life that falls squarely within the the right to privacy. In such cases, the couple together made the decision to create a family through the use of assisted reproduction, and the preembryos would not exist but for that joint decision. Therefore, gamete and non-gamete providers should be afforded equal constitutional protection in disputes over frozen preembryos.

Contracts↗

ACOG Committee Opinion No. 347, November 2006: Using preimplantation embryos for research.

Human embryonic stem cell research promises an increased understanding of the molecular process underlying cell differentiation. Transplantation of embryonic stem cells or their derivatives may, in the future, offer therapies for human diseases. In this Committee Opinion, American College of Obstetricians and Gynecologists (ACOG) Committee on Ethics presents an ethical framework for examining issues surrounding research using preimplantation embryos and proposes ethical guidelines for such research. The Committee acknowledges the diversity of opinions among ACOG members and affirms that no physician who finds embryo research morally objectionable should be required or expected to participate in such research. The Committee supports embryo research within 14 days after evidence of fertilization but limits it according to ethical guidelines. The Committee recommends that cryopreserved embryos be the preferred source for research but believes that the promise of somatic cell nuclear transfer is such that research in this area is justified. The Committee opposes reproductive cloning. Intended parents for whom embryos are created should give informed consent for the disposition for any excess embryos. The donors of gametes or somatic cells used in the creation of such tissue should give consent for donation of embryos for research. Potential research projects should be described to potential donors as much as possible. Donation of embryos for stem cell research requires specific consent. The Committee believes that compensation for egg donors for research is acceptable, consistent with American Society for Reproductive Medicine guidelines.

Cloning, Organism↗

Cryopreserved human embryos in Canada and their availability for research.

OBJECTIVE: To determine the number of cryopreserved human embryos at all Canadian in vitro fertilization (IVF) clinics, the number of these embryos that have been donated to research, and the consent processes regarding the disposition of embryos no longer required for reproductive purposes. METHODS: A questionnaire was mailed to 24 fertility clinics identified as conducting IVF and cryopreservation, inviting completion of the questionnaire by telephone. Thirteen clinics (response rate 54%) completed the survey. RESULTS: As of August 2003, all 13 clinics cryopreserve embryos not required for intrauterine transfer; in total, 15,615 embryos are currently in storage in these clinics. Nine clinics specifically offer patients the option of donating embryos to research; in total, 299 embryos have been allocated for research, about 2% of all embryos stored by these 13 clinics. All 9 clinics routinely seek consent for research use of embryos, with 7 clinics currently using such embryos for research to improve clinic practices. CONCLUSION: The results highlight the difficulties of gathering accurate data on assisted human reproduction and related research in a context where there is no legislation governing these practices. Nonetheless, the data suggest there are very few cryopreserved embryos in Canada available for research and that even fewer of these may be potentially eligible for research due to incomplete or inadequate consent processes.

Canada↗

Ethical questions concerning research on human embryos, embryonic stem cells and chimeras.

Research using human embryos and embryonic stem cells is viewed as important for various reasons. Apart from questions concerning legal regulations, numerous ethical objections are raised pertaining to the use of surplus embryos from reproductive medicine as well as the creation of embryos and stem cells through cloning. In the hopes of avoiding ethical problems, alternatives have been proposed including the extraction of egg cells from "dead" embryos derived from in vitro fertilization procedures, the extraction of pluripotent stem cells from blastocysts, technologies such as "altered nuclear transfer" (ANT) and "oocyte-assisted reprogramming" (ANT-OAR) as well as parthenogenesis. Initial ethical assessments show that certain questions pertaining to such strategies have remained unanswered. Furthermore, with the help of new or more differentiated biotechnological procedures, it is possible to create chimeras and hybrids in which human and non-human cells are combined. Human-animal chimeras, in which gametes or embryonic tissue have been mixed with embryonic or adult stem cells, demonstrate a different "quality" and "degree of penetration" from those produced in previous experiments. Not only does this have consequences regarding questions of patentability, this situation also raises fundamental questions concerning the human being's self image, the concept of person, identity and species and the moral rights and duties that are connected with such concepts. There is a need for legal regulation, on the national as well as the international level.

Cloning, Organism↗

Secondary donation of frozen embryos is more common after pregnancy initiation with donated eggs than after in vitro fertilization-embryo transfer and gamete intrafallopian transfer.

OBJECTIVE: To determine the availability of donated cryopreserved embryos. DESIGN: Retrospective review. SETTING: Community hospital-based donor oocyte program. PATIENT(S): Eighty-nine consecutive infertile couples and women who had 94 sets of embryos cryopreserved after pregnancy initiation with unfertilized donated eggs between January 1, 1991 and December 31, 1996. INTERVENTION(S): Cryopreservation of fertilized ova or cleaving embryos. MAIN OUTCOME MEASURE(S): Disposition of frozen embryos as of June 1, 1997. RESULT(S): Of the 94 sets of frozen embryos, 52 (55.3%) were thawed into the original recipient. At an average of 30 months since the treatment cycle, 26 (27.7%) sets of embryos remain in storage. Of the 16 sets of embryos not thawed for transfer, 11 sets (11.7%) were donated and 5 sets (5.3%) were destroyed. The fraction of spare embryos donated was much higher after pregnancy initiation with unfertilized donated eggs than after IVF-ET and GIFT (68.8% versus 19.1%, respectively). CONCLUSION(S): Couples and women who did not use their frozen embryos after pregnancy initiation with unfertilized donated eggs were twice as likely to donate them as to have them destroyed. Secondary donation of cryopreserved embryos was much more common after pregnancy initiation with unfertilized donated eggs than after standard IVF-ET and GIFT.

Adult↗

Ethical issues in deriving stem cells from embryos and eggs.

Human embryonic stem cell (ESC) research has attracted wide media coverage. It has been headline news for the past several months, revealing the complex case of Professor Hwang Woo-Suk and the scientific fraud where he purported to have created the first human patient-specific stem cell lines generated by cell nucleus replacement (CNR). To ethically obtain the raw materials (eggs, sperm and embryos) for human ESC research is an enormous challenge, yet essential if this research is to proceed in its quest to try to deliver some of the expectations placed upon it: developing treatments and possible cures for a range of serious diseases. This article examines some of the ethical issues surrounding human ESC research using the four principles frequently applied to healthcare and medical research; autonomy, beneficence, non-maleficence and justice. The author strives to ask questions throughout which will encourage debate and discussion.

Attitude to Health↗

Cryopreservation.

Embryo cryopreservation is now firmly established as a routine component of in vitro fertilization (IVF) and other assisted conception techniques for the resolution of human infertility. Excess fertilized oocytes and embryos can be preserved for infertile couples avoiding the necessity to replace large numbers of embryos which reduces the incidence of multiple births and their sequelae. The additional pregnancies obtained from replacement of cryopreserved embryos has effectively increased the success rate of a cycle of IVF treatment for a couple by 1 to 10%. There is an increasing preference to cryopreserve fertilized pronuclear oocytes by slow cooling in 1,2-propanediol (PROH) although many clinics also cryopreserve early cleavage stage embryos by slow cooling in PROH or dimethyl sulphoxide (DMSO) with similar success rates to those for pronuclear oocytes. Numerous problems have appeared with the attempted cryopreservation of mature unfertilized oocytes, including nonreversible disassembly of the meiotic spindle during cooling, reduced fertilization rates due to the effects of cryoprotectants and cooling on the zona pellucida, parthenogenetic activation of oocytes by PROH, substantially increased polyploidy and aneuploidy when frozen-thawed oocytes are fertilized and increased cryoinjury to unfertilized oocytes when compared to fertilized oocytes. It is also necessary to address problems which have arisen through the disagreement of separated couples about the disposition of embryos in cryostorage.

Cryopreservation↗

Ethical issues involved with in vitro fertilization.

There are three elements to consider with in vitro fertilization. First, the paramount concern needs to be the well-being and best interests of the child, even though he or she may be an embryo at the time. Second, some people think a child will solve their marital problems. Although couples seeking in vitro fertilization should not be subjected to more scrutiny than couples conceiving in the traditional way, the stresses and uncertainties of in vitro fertilization can further strain a marriage. Clinic staff members should be sensitive to this issue as a way of helping to avoid complications later. Third, how we resolve the status and fate of the frozen embryo and who has disposition over it surely will reflect how we consider abortion rights. For example, if the standards of Roe vs Wade were applied, one could argue that the woman should have total disposition over the frozen embryo. On the other hand, if the father receives a say in the matter, what impact would this have? Given the nature of our society and the tenuous state of marriage, the problem of disposing frozen embryos is a critical one that has no satisfactory solution. Finally, there is the stress factor. Although this is not an issue of direct ethical concern, it is related to the necessity of the couple receiving accurate information. If the couple receives an incorrect impression of a clinic's success rates, they may be exposed unnecessarily to further stress and frustration.(ABSTRACT TRUNCATED AT 250 WORDS)

Ethics, Medical↗

Some ethical and legal issues in assisted reproductive technology.

The potential and actual applications of reproductive technologies have been reviewed by many governmental committees, and laws have been enacted in several countries to accommodate, limit and regulate their use. Regulatory systems have nevertheless left some legal and ethical issues unresolved, and have caused other issues to arise. Issues that regulatory systems leave unresolved, or that systems have created, include disposal of embryos that remain after patients' treatments are concluded, and multiple implantation and pregnancy. This may result in risks to maternal, embryonic and neonatal life and health, and the contentious relief that may be achieved by selective reduction of multiple pregnancies. A further concern arises when clinics must (or choose to) publicize their success rates, and they compete for favorable statistics by questionable patient selection criteria and treatment priorities.

Embryo Disposition↗

Spare embryos: 3000 reasons to rethink the significance of genetic relatedness.

IVF laws in Victoria, Australia provide that human embryos must not remain in storage in excess of 5 years. Studies reviewing the fate of surplus human embryos reveal that close to 90% of couples choose to discard their excess embryos and that hundreds of embryos are disposed of annually. It has been argued that human embryos are a valuable resource and that there is a need to consider educational programmes to encourage couples to donate spare embryos to other infertile couples, rather than discard them. Surveys show that one reason that so few embryos are donated is that couples attach great significance to genetic parenthood. Advances in reproductive technology may necessitate a review of biological definitions of family and the importance of genetic relatedness. It can be argued that it is unreasonable to conclude that genetic ties are so significant that embryos should be discarded rather than donated and raised by non-genetically related parents. It is suggested that education programmes should encourage reflection on people's beliefs about the importance of genetic relatedness with regard to what makes a family. Open embryo donation or directed embryo donation programmes might cause couples to change their minds, or alleviate their anxiety about donating embryos to others.

Attitude↗

Minimizing risk in anonymous egg donation.

Assisted conception carries with it known and putative medical and surgical risks. Exposing healthy women to these risks in order to harvest eggs for donation when a safer alternative exists is morally and ethically unacceptable. Egg sharing minimizes risk and provides a source of eggs for donation. Anonymity protects all parties involved and should not be removed.

Embryo Disposition↗

Factors influencing the decision to use or discard cryopreserved embryos.

BACKGROUND: Couples' reasons for discarding supernumerary fertilized cryopreserved embryos and gender differences in attitudes toward the frozen embryos were investigated among Swedish couples undergoing in vitro fertilization (IVF) at a private clinic. At the time of the study Swedish law stipulated that couples could keep their frozen embryos for a maximum of one year, with the possibility of an extension based on individual requests. METHODS: A questionnaire with structured and unstructured questions was sent to 124 women and 124 men who had entered the IVF treatment and obtained supernumerary embryos from 1 January 1994 to 1 March 1995. Eighty-two women and 74 men completed the questionnaire. RESULTS: After a mean storage time of 25.3 (+/-11.0) months 22 (26.8%) of the responding couples had their embryos discarded. The reasons were mainly practical, such as a positive outcome of IVF and a legally too short storage time. Comparisons between women and men showed that fewer women (13;17.6%) than men (20;27%) had been uncertain during the IVF treatment about using the frozen embryos at a later date and that men more often than women expressed anxieties about possible effects of the freezing procedure on the potential child (p=0.009). CONCLUSION: A positive outcome of the original IVF treatment and a short maximum legal time of cryopreservation were the most common reasons why couples discarded their embryos. The men more often than women expressed anxieties about possible effects on a potential child. The results emphasize the need for giving detailed information to the couples about cryopreserved embryos and children born by this method.

Adult↗