Embryo donation for medical research: attitudes and concerns of potential donors

Catherine A. McMahon1,5, Frances L. Gibson1, Garth I. Leslie2, Douglas M. Saunders2,4, Katherine A. Porter4 and Christopher C. Tennant3

1 Royal North Shore Hospital, Sydney, Departments of 2 Obstetrics and Gynaecology and 3 Psychological Medicine, University of Sydney Northern Clinical School at Royal North Shore Hospital Sydney and 4 North Shore Fertility, North Shore Fertility, Sydney, Australia

5 To whom correspondence should be addressed at: Department of Psychology, Macquarie University, North Ryde, 2109, NSW, Australia. e-mail: cmcmahon{at}psy.mq.edu.au


    Abstract
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
BACKGROUND: The recent derivation of embryonic stem cell lines from human blastocysts and related implications for regenerative medicine has intensified a longstanding debate about the use of human embryos for research purposes. However, studies have shown that few couples with stored embryos opt to donate them for research. Herein, the attitudes and concerns of potential embryo donors to donation of surplus embryos for medical research were examined. METHODS: From a total of 509 couples who had stored frozen embryos and who had received a questionnaire about embryo donations for medical research, 152 women (30%) and 123 male partners (24%) responded. Embryos had been stored for a mean of 2.25 years (range 3 months to 12 years). RESULTS: Some 10% of respondents indicated it probable, and 34% possible, that they would donate their surplus embryos for research in the future. Women respondents whose embryos had been stored longer, and those committed to the practice of a religion, were more worried about their embryos. Respondents positively disposed to donation commented on their desire not to waste embryos, a desire to help infertile couples, and/or to advance scientific knowledge. Those with negative views commented on the embryo as a potential child and expressed concerns about a perceived lack of control over the type of research to be carried out. CONCLUSIONS: Findings indicate a need for tailored education and counselling about embryo donation for medical research.

Key words: attitudes/embryo donation/medical research


    Introduction
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
Research on human embryos has always been controversial because of the tension between societal interests in medical breakthroughs and concerns about treating human embryos with respect. Since the 1980s there has been a longstanding and intense public debate about the moral and legal status of the embryo. On the one hand are those who confer the same moral status to human embryos as to children and adults and believe that the destruction of living embryos for research is immoral and unnecessary (Doerflinger, 1999Go). Others, who would accord a lesser moral status to undifferentiated embryos, tend to argue that societal interests in health and scientific progress justify experimentation on embryos, and that "the pre-embryo deserves greater respect than that accorded to human tissue, but not the respect accorded to actual persons" (Ethics Committee of the American Society for Reproductive Medicine, 1997). Until recently, research on human embryos was directed largely to improving fertility treatment, pre-implantation genetic diagnosis and other procedures related to reproduction. The recent derivation of embryonic stem cell lines from human blastocysts, cloning of human embryonic stem cells, and demonstration of their amenability to genetic manipulation has broadened and intensified the debate by attracting significant public attention to the far-reaching potential applications of these cells in the areas of developmental biology, drug discovery and regenerative medicine. The area of embryo research has now moved beyond the relatively narrow world of infertility treatment into the broader world of cell therapies.

These developments excite some sectors of the community and raise alarm bells for others. While some argue that the only acceptable stem cell research should be conducted with stem cells from adult lines, others believe that it is acceptable to use ‘spare’ or surplus human embryos for stem cell research, because they would otherwise be destined for destruction. However, it is currently generally considered unacceptable for embryos to be deliberately created in order to be destroyed (Lenoir, 2000Go). Recently, it has been argued that there are fewer ethical concerns about the production of embryonic stem cells using therapeutic cloning "as the moral status of an enucleated egg transplanted with a somatic cell nucleus is more clearly not equivalent to that of a human being" (Hansen, 2002Go).

It has been noted (Bonnicksen, 2001Go) that while numerous ethical bodies around the world are grappling with these issues, voices from the private fertility clinics are also needed and welcome. Perhaps the voice that has been heard least is that of the potential providers of ‘spare embryos’. Generally, these are couples undergoing (or having completed) treatment for infertility. Because many more oocytes are retrieved and fertilized than are transferred back to the couple, it is usual for couples to have surplus embryos cryopreserved, providing the opportunity for later use in treatment. There is an enormous cumulative backlog of human embryos in long-term storage in fertility clinics around the world, with recent reports documenting 71 776 cryopreserved embryos in Australia at the end of 2000 (Hurst and Lancaster, 2001Go). These frozen embryos pose significant dilemmas both for couples who have completed treatment and/or do not want further children (Jones, 1990Go; McMahon et al., 2000Go) and for the fertility clinics where the embryos are stored (Edwards and Beard, 1997Go; Oghoetuoma et al., 2000Go). While recent studies have examined decision making and attitudes regarding discarding versus using surplus embryos (Klock et al., 2001Go; Svanberg et al., 2001Go) and donation to other infertile couples (Kingsberg et al., 2000Go; Söderström-Anttilla et al., 2001Go), few studies have specifically examined attitudes of potential donors to donation for medical research.

The existing research consistently demonstrates that only a small percentage of ‘owners’ of ‘spare’ embryos donate them for research purposes (Laruelle and Englert, 1995Go; Lornage et al., 1995Go; Darlington and Matson, 1999Go; Van Voorhis et al., 1999Go; Oghoetuoma et al., 2000Go), or express an intention to do so in the future (McMahon et al., 2000Go). An Australian study interviewing a small sample of IVF parents regarding their surplus embryos revealed that the embryo ‘owners’ appear to have a very personal view of the embryo as a potential child which influences their attitudes to donation for medical research (McMahon et al., 2000Go). In order to explore further these findings, a larger survey of all couples with frozen embryos in storage at a fertility clinic in metropolitan Sydney, Australia was conducted. The study aimed to explore attitudes to future embryo donation for medical research and to examine factors which may encourage or dissuade people from donating embryos for research.


    Materials and methods
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
Procedure
Prior approval for this study was obtained from the Ethics Committee at the local teaching hospital. Two questionnaires (one for each parent) with a postage-paid return envelope were sent to 549 clients selected from a list of 874 clients who had frozen embryos in storage at a private metropolitan fertility clinic in Sydney, Australia. The selection criteria involved four factors. Patients were not sent questionnaires if their current address was unknown and/or their partner was deceased, if they had not responded to letters regarding their stored embryos for more than 10 years, and if the embryos had been stored for less than 3 months. Couples (in an Australian context) are aware they have four options with respect to their frozen embryos: to use them in subsequent treatment cycles; to donate them to another couple; to donate for research; or to allow the embryos to succumb. A fifth option is to defer the decision and leave the embryos in storage. Couples in this sample can opt for a 1- or 3-year storage plan. If at the end of that time they still have embryos stored, a letter is sent regarding their intentions. They can elect for continued storage on either plan for up to 10 years. A storage fee is paid.

Participants
Of the 549 couples to whom questionnaires were sent, 40 could not be located at the recorded address, leaving a sample of 509 who received the questionnaires. A total of 152 replies was received from women (response rate 30%), and 123 from their male partners (response rate 24%). There were no cases where men responded and their partners did not. The average (±SD) age of women respondents was 36.1 ± 3.9 (range 29–49) years, and for men was 38.9 ± 5.7 (range 30–67) years. Some 53% of both men and women were tertiary educated, and 91.5% were Caucasian. These demographic characteristics were consistent with the general demographic profile of clients at the infertility clinic. Some 33% were Catholic, 48% Protestant, 2% Jewish, 0.5% Hindu and 0.5% Muslim; 16% of patients reported no religious affiliation. Of those who reported a religious affiliation, 14% reported they were very committed to the practice of their religion, 44% reported moderate commitment and 56% reported they were either only slightly or not at all committed to the practice of their religion. Comparative data regarding religious affiliation and commitment for the clinic population as a whole are not available. In total, 25% of the respondents reported a diagnosis of female infertility, 30% male infertility, 10% combined male and female infertility and 35% unknown diagnosis. Embryos had been stored for an average of 2.25 years (range 3 months to 12 years), and the average number of stored embryos was 4.5 (range 1–16). The diagnostic profile of the respondents was comparable with that of the overall client population, as was the number of stored embryos (overall average 4.3, range 1–16). Sixty-eight percent of respondents had at least one child conceived through IVF; only 23% of respondents indicated that they had completed their families. Comparable data were not available for the non-respondents.

Questionnaire
Attitudes to embryos
Using six-point Likert rating scales, couples were asked whether they thought of their embryos as potential children (response range ‘definitely not’ to ‘definitely’), whether they worried about what decision to make regarding their frozen embryos (response range ‘almost never’ to ‘often’) and whether they considered embryo donation as analogous to organ donation and/or blood donation (response range ‘completely different’ to ‘identical’). Six-point scales were deliberately chosen to avoid a ‘neutral’ response so that attitudinal responses could also be recoded and considered as dichotomous variables.

Attitudes to donation for medical research
Couples were then asked to indicate their current thoughts about the likelihood that they would donate the embryos for medical research. Response options were ‘very unlikely’, ‘possibly’ and ‘probably’. Space was provided for the respondents to add further comments.

Couples were also asked to indicate whether they had sought counselling from either medical staff or counsellors regarding what decision to make with respect to their embryos.

Data analysis
All statistical analyses were performed using the Statistical Package for the Social Sciences (SPSS Version 10). First, frequencies were calculated for responses to questions on attitudes, followed by group means and standard deviations.

In the second stage of analysis, attitudinal responses (not normally distributed) were recoded dichotomously to examine relationships between demographic and treatment history variables, worry about decision making with respect to stored embryos and intention to donate for medical research. Given the large number of religions and small cell sizes, subjects were coded as ‘non-religious’ (no religious affiliation/religious affiliation but slight or no commitment) versus ‘religious’ (religious affiliation/moderate or high commitment). Preliminary correlational and chi-square analyses were used to reduce redundancy among demographic and treatment history variables. Subsequently, logistic regression analyses examined which of the following variables predicted worry about embryos and intention to donate: age, time embryos stored, religious commitment, gender and whether or not couples had completed their families. Statistical significance was defined as a P-value < 0.05.

Finally, in the third stage of analysis, all spontaneous comments offered by respondents (n = 40) to the question regarding the likelihood of donating embryos for medical research were analysed. Transcripts of the comments were reviewed by the first author to identify themes. Responses were first categorized as ‘inclined to donate for research’ or ‘not inclined to donate for research’. Within each of these major categories, responses were further subclassified according to the reason given. This yielded seven categories in total. All responses were then coded independently by both the first author and the second author. A comparison of the two sets of classifications revealed agreement between the two coders in 88% of cases. Disagreements were resolved through conferencing.


    Results
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
Attitudes to embryos
Responses to the survey questions regarding whether respondents thought of their embryos as potential children, the extent to which they worried about decision making regarding the embryo, and views on similarities between embryo donation and blood and organ donation are summarized in Table I.


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Table I. Attitudes to embryo donation: means (±SD) frequencies for Likert scale responses
 
Likelihood of donating for medical research
Some 56% of respondents indicated that it was very unlikely they would donate their surplus embryos for medical research, 34% said it was possible, and 10% indicated they thought it a likely decision. With respect to worry about the embryos, women (P = 0.015), those whose embryos had been in storage longer (P = 0.002) and those more committed to the practice of religion (P = 0.008) were more worried. The regression statistics in the reduced model are detailed in Table II. There were no significant predictors of intention to donate embryos, although there was a non-significant trend for those who were religious to be less inclined (Wald chisq = 2.73, d.f. = 1, P = 0.098).


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Table II. Statistics for reduced regression model predicting worry about embryos
 
Counselling regarding decision making with respect to embryos
None of the respondents had sought ‘formal’ counselling regarding the decision-making process from either medical or counselling staff.

Views expressed by couples regarding embryo donation for medical research
Forty respondents (29 women, 11 men) made comments on the questionnaire regarding the option of donating embryos for medical research. Comments reflected both positive and negative orientations. There were three themes underpinning a positive attitude: the importance of not wasting embryos; the explicit desire to help other infertile couples; and more general comments indicating that donation for research was desirable. Four themes underpinned a negative attitude: an explicit view of the embryos as potential children; reservations about the type of research that might be conducted; a view that other options (e.g. donating to infertile couples) were preferable; and a more non-specific negative orientation. Tables III and IV present a summary of the comments received organized according to orientation to donation and themes respectively. All comments (including those which were somewhat ambiguous or general) have been included to avoid selection bias. Where several couples made identical or very similar comments the comment was noted only once.


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Table III. Comments reflecting a positive orientation to donation for medical research
 

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Table IV. Comments reflecting a negative orientation to donation for medical research
 

    Discussion
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
Overview of findings
Study findings need to be interpreted with caution, given the low response rate and the fact that the majority of respondents had not yet completed their families. Notwithstanding these limitations, the study findings, particularly respondent comments, are informative regarding factors and issues which may encourage or discourage people from donating embryos for research. The study results showed that the majority (80%) of ‘embryo owners’ who did respond to the survey are inclined to think of their embryos as potential children, with 51% indicating that they definitely thought this way. This figure was higher than that reported by others (Laruelle and Englert, 1995Go) who noted that about 30% of couples about to undergo IVF treatment viewed their embryo as a child. In the current study, however, couples had already begun treatment and 68% already had a child conceived through IVF. Earlier research (McMahon et al., 2000Go) indicated that the existence of a child conceived through IVF influences couple perceptions of remaining embryos.

Very few respondents viewed embryo donation as in any way analogous to organ or blood donation. Some 35% of respondents reported some concern about what to do about their stored embryos, with 12% indicating a great deal of concern. Female respondents, respondents whose embryos had been stored for longer, and respondents who reported commitment to the practice of a religion were more worried. It is interesting to note that while 77% of couples indicated that they had not yet completed their families, whether or not respondents had completed their families was not significantly related to worry about the embryos. Concerns seemed more related to pre-existing religious beliefs than to current circumstances and future intentions. There are two possible interpretations for the finding that those whose embryos had been stored for longer were more worried. First, it seems plausible that the longer embryos have been stored, the more pressing the need to make an acceptable decision, although as noted above couples in the current study do have up to 10 years to decide. It is also possible that couples who feel more worried and ambivalent about their embryos throughout the treatment process may leave them in storage for longer periods in the hope that a difficult decision will be taken out of their hands (Svanberg et al., 2001Go).

Only 10% of respondents indicated that it was likely they would donate their embryos for research; however, a further 34% indicated that this was possible. This was consistent with figures reported in other studies (Van Voorhis et al., 1999Go) and with data from the clinic during the period 1986–2001 which revealed that 29% of patients with stored embryos did, in fact, donate for research. There were no significant predictors of intention to donate, although there was a trend for those who were more religious to be less inclined to do so. It is noteworthy that those who had completed their families were not more likely to indicate an intention to donate their embryos for research.

Spontaneous comments made by the respondents regarding embryo donation for research purposes reveal a number of factors which may underpin their decision making and their dilemmas about it. Three themes emerged with respect to a positive orientation to donation for medical research. The first was the idea that it was preferable to use embryos for research rather than to destroy or waste them. A number of respondents commented on the effort (both physical, emotional and financial) that had gone into creating the embryos. Similar feelings have been noted regarding the value placed on a child conceived through IVF (Gibson et al., 1998Go). Altruism, expressed as a desire to help other infertile couples and/or advance scientific and medical knowledge, was also considered a reason to donate for research. Again, these feelings of gratefulness and a desire to give something back have also been noted in infertile couples after conceiving through IVF (Lind et al., 1989Go). A third subgroup was positively inclined and made positive general statements about research.

A view of the embryo as a potential child was salient in comments reflecting a negative view of donation for research. Some used quite strong emotional language and vivid imagery regarding the concept of their embryo as a ‘specimen’ and what the medical research might entail. Others referred to the babies they might become. As noted above, 68% of respondents had an existing child conceived through IVF. In an earlier study (McMahon et al., 2000Go), the parents of 5-year-old IVF children who were interviewed regarding their stored embryos, often referred to them as coming ‘from the same batch’ and commented on the psychological impact of having seen them under the microscope.

The second major concern was a perceived lack of control over what type of research might be conducted. Some respondents were positively disposed towards research which might lead to curing disabilities (such as stem cell research), or research which would directly benefit other infertile couples, but wary about ‘research without justification’. There were both implicit and explicit concerns focused around cloning, in particular. Once again, there were some vivid images of an undesirable ‘brave new world’: "I don’t want the embryos to become little me’s in little jars or bottles placed on lab shelves, little babies in bottles". No doubt sensational reports about cloning in the media contribute to these concerns.

While caution is needed in generalizing from these comments, reluctance to donate embryos for medical research may reflect very personal feelings and attitudes related to the pain of infertility, the struggle to conceive and the meaning invested in the embryos which are viewed as potential and highly sought-after children.

It is a noteworthy finding that despite the fact that almost half the respondents indicated some concern about the decision, and some had embryos stored for as long as 12 years, none had sought ‘formal’ counselling regarding this issue. However, anecdotal reports from clinic staff suggest that many have engaged in ‘informal’ counselling during telephone conversations with the cryopreservation manager regarding their stored embryos.

Clinical implications
Reservations that couples expressed regarding ‘experimentation’ on embryos indicate that the aims and potential benefits of medical research in this area may not be well understood. It has been noted (Laruelle and Englert, 1995Go) that the aims of medical research are often not explained well to the public, and medical experiments have always been a rich area for fantasies. The word ‘cloning’ in particular has emotional connotations and there is frequently confusion between the reproductive cloning of asexual reproduction (as in ‘Dolly’ the sheep) and non-reproductive cloning which would be incapable of leading to the birth of a human being, but could open the way to research with major therapeutic potential.

The comment has been made (Bahadur, 2001Go) that the success of recruiting altruistic donors for medical research is likely to be associated directly with the attitudes and structures in which reproductive technologists operate. Improved communication and education, including consideration of consent processes which give donors explicit control over the ways in which their donated embryos will and will not be used, may facilitate the decision-making process. It may also be beneficial routinely to provide education and counselling prior to commencement of treatment (Kingsberg et al., 2000Go), as well as later in the treatment process.

Decision-making concerning infertility is a continuous and complex process, in which different concerns and dilemmas arise at different times (Van Balen, 1997Go). One group (Klock et al., 2001Go) reported that 71% of couples in their sample thought that counselling prior to embryo disposition was needed. However, despite the complexity of the dilemmas faced and the fact that counselling is available to all couples, none of the couples in the current study had made an appointment to discuss their dilemmas regarding their embryos with either medical staff or counsellors (counselling is mandatory when couples consider donation of their embryos to another infertile couple). This low participation in counselling is consistent with other research. It has also been reported (Boivin, 1997Go) that despite a widespread belief that women undergoing IVF treatment need supportive counselling, only about 15–20% of women avail themselves of such treatment. Boivin argues that even those mothers who do not require formal counselling would benefit from access to more information. Approaches to counselling need to be tailored to the needs of different groups of clients at different stages in the treatment process (Van Balen and Visser, 1997Go; Svanberg et al., 2001Go). Information evenings and educational brochures regarding options with respect to surplus embryos may be appropriate in the first instance to provide couples with an opportunity to clarify their understanding of what various options entail and an opportunity to voice their concerns.

Study limitations and directions for future research
The low response rate (30% of women and 24% of men) means that these study findings must be interpreted with caution. This low response rate is consistent with reports from fertility clinics regarding the poor response they receive to letters asking about intentions with respect to embryos (Edwards and Beard, 1997Go; Oghoetuoma et al., 2000Go), but much lower than the response rate achieved in another study exploring couples intentions to use or discard their surplus embryos (Svanberg et al., 2001Go). This may be due to research methodology (Svanberg and colleagues sent two reminders to non-respondents) or to the long storage option (10 years) for couples in the current study.

Where possible, comparisons have been made between respondents and the overall clinic population of clients with stored frozen embryos, and these comparisons suggest that respondents are similar to the general client profile with respect to age, diagnosis of infertility, number of embryos stored and time embryos were stored. Comparative data are not available, however, regarding whether respondents differed from non-respondents as to whether they had completed their families and were religiously committed. The heterogeneous nature of the sample is also a limitation. A future study that specifically targeted those whose embryos have been stored for more than three years and or those who had completed their families could be more informative. In addition, given the comments that couples made about a desire for control over what sort of research would be done, future studies would be well advised to allow couples to distinguish with respect to their willingness to donate for different types of medical research.

In conclusion, the results of the present study were consistent with a small body of existing research data in demonstrating that despite the enormous and growing backlog of stored frozen embryos, and growing awareness of the potential benefits of stem cell research, a minority of couples who ‘own’ surplus embryos intend to donate them for that purpose. It is of course possible that when forced to make a decision—that is, when continued storage or the utilization of embryos for further treatment cycles is no longer an option—more couples may in fact opt to donate for research. Indeed, it is a noteworthy finding of the current study that 44% of participants were open to the idea.

However, it is clear that potential donors have reservations and need more information about the type of research to be conducted, and what benefits the research may provide for others. The current study also suggests that potential donors desire more control over the consent process and may wish to specify which types of research are acceptable to them. Finally, the findings of the present study indicate that it is timely to include the voice of potential donors of embryos into the debate about stem cell research.


    Acknowledgements
 
The authors thank Felicity Garner of North Shore Fertility for her comments on the questionnaire, and also the clients and staff of North Shore Fertility for their co-operation in this research project. Financial support with respect to printing and postage of questionnaires was provided by the Department of Psychological Medicine, Royal North Shore Hospital. Computing facilities and access to databases were provided by North Shore Fertility.


    References
 Top
 Abstract
 Introduction
 Materials and methods
 Results
 Discussion
 References
 
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Submitted on September 9, 2002; resubmitted on December 10, 2002; accepted on January 3, 2003.