Department of Obstetrics and Gynaecology, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
1 To whom correspondence should be addressed. Email: m.a.porter{at}abdn.ac.uk
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Abstract |
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Key words: embryo transfer/emotions/feasibility/IVF/human
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Introduction |
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A number of trials have shown that elective single embryo transfer (SET) can significantly reduce the incidence of twins and higher order pregnancies without compromising cumulative live birth rates per couple (Gerris et al., 1999; Martikainen et al., 2001
; Thurin et al., 2004
). This policy is opposed by those who fear a reduction in success rates per treatment. Although common in some Northern European countries, elective SET is far from being universally accepted in the UK and other parts of the world (Bhattacharya and Templeton, 2004
) where the bulk of IVF treatment is self-funded.
Published data from observational studies suggest that despite awareness of the risks, some couples find the prospect of a twin birth quite acceptable and indeed preferable to childlessness (Gleicher et al., 1995; Goldfarb et al., 1996
). Even the minority of couples who favoured SET felt that it would only be acceptable if existing pregnancy rates were maintained (Murray et al., 2004
).
Thus, in the current climate, more information is necessary before SET can be adopted into routine clinical practice. Its clinical and cost-effectiveness as well as acceptability needs to be proven in the context of more multi-centred randomized controlled trials (RCT) (Ozturk et al., 2001). The quality of such trials would be enhanced by increased methodological rigour and high levels of participation on the part of the eligible population. However, it is not known whether it would be possible to recruit couples to such a trial in the future. It is not unusual for clinical trials to be delayed or abandoned because of inability to recruit sufficient subjects in the time available (Centre for Information and Study on Clinical Research Participation, 2004) or lack of equipoise among patients and staff (Edwards et al., 1998
; Lilford, 2003
). The methodological literature relating to RCTs in infertility is limited, focusing mainly on statistical issues. There has been little work on the patient's perspective and factors influencing their decision to participate in a trial. Similarly, data about staff attitudes towards enrolling fertility patients in randomized trials are scarce. Only Hartshorne and Lilford (2002)
have looked at the differing attitudes of staff and patients in a particular aspect of IVF treatment.
The aim of this study was to explore the views of staff and couples towards a proposed trial comparing SET with double embryo transfer (DET), and to ascertain what would be the most acceptable trial design. Qualitative methods are the best means of exploring views and issues and formulating theories about hitherto unexamined behaviour (Mason, 2002). As the spotlight was on ideas rather than experiences, it was felt that focus group discussions (FGD) would provide staff and patients with a relatively safe environment in which to share ideas, beliefs and attitudes in the company of people in a similar situation (Morgan, 1993
). According to Madriz (2000)
the collective nature of the group interview decreases the power of the interviewer relative to the participants and validates their choices and experiences. Focus groups have already proved a useful vehicle for involving patients in the design of trials of contentious treatments (Koops and Lindley, 2002
).
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Materials and methods |
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Approximately 20 couples were selected at random from those on the waiting list for IVF treatment. We felt that it was important to elicit couples views about a proposed trial prior to exposure to any IVF treatment and associated stress. They were not currently involved in any other research project and were informed of the study by letter. Only one couple agreed to participate in a FGD. As topics such as equipoise and randomization have proved difficult for patients to grasp when asked to participate in a trial (Mills et al., 2003) it was thought that a FGD would enable couples to share ideas and learn from one another about a hypothetical situation. However, a second attempt to recruit couples through the clinic yielded no more participants, and this approach was abandoned in favour of individual interviews with the first 12 couples who agreed. It was felt that this would be sufficient to obtain a wide range of views on these issues. Although sensitive topics are not ideal material for FGD and this response might have been predicted (Madriz, 2000
), the main objection seemed to be the inconvenience of attending a specially convened evening meeting. After explaining the study in detail and obtaining their written consent, couples were interviewed together immediately after their initial visit prior to starting their first IVF cycle. Interviews were conducted by an experienced non-clinical researcher (M.P.) and lasted 1520 min (see Appendix 2). The nature of the interviews was dictated by constraints on couples time and their preference for an interview following a clinic consultation. As this lasted >1 hour, consecutive individual interviews were deemed too tiring and time-consuming. The interviews were tape-recorded, transcribed in full and analysed thematically using an inductive approach. One researcher (M.P.) coded all transcripts including that of the FGD by question first, and the results were then examined for consistent themes. Deviant cases were also examined to see how they fitted into or diverged from the emerging themes. Consistency was achieved by having the second researcher (S.B.) examine some of the transcripts and discuss the codes assigned.
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Results |
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Demographic profile of respondents
Three embryologists, three clinicians (qualified gynaecologists specializing in infertility and assisted reproduction), three nursing sisters and a counsellor were included in the staff group. Only one member of staff was male. Their ages ranged from approximately 25 to 55 years. The 12 couples had a mean duration of infertility of 4.5 years and the women's ages ranged from 32 to 42 years with a mean of 37.5. Half of the men worked in white-collar and half in manual jobs; all of the women worked in white-collar jobs. Five of the couples had male factor infertility alone, two ovulatory factors alone, one unexplained, one tubal and three a combination of factors.
Risks of twins
Staff views
Staff were well aware of the reported risks to mothers and babies associated with twin pregnancies. Most had direct experience of couples having problems with twin pregnancies, although physical and mental disabilities were not mentioned. They have either lost them at various stages, or one twin has died or both in the early stages of the pregnancies, 1620 weeks. So the trauma for the couples going through that is quite horrendous. (Midwife 1). They varied in how concerned they were personally, but agreed that patients did not want to know about the risks of twin and higher order pregnancies, as the following interchange shows: ... there is some responsibility on us. We should put across to them that there are some complications associated with having two or more babies ... (Doctor 2). They can hear what you have said but they are not sort of listening. They just say Yes, yes, yes, two embryos please. (Embryologist 1). Staff felt that patients did not believe that the risks applied to them and saw two babies as a bonus, precluding the need for further treatment. Staff cited cases where fruitless efforts had been made to dissuade couples from having three embryos replaced. As one midwife said: ... I think it would be very hard to persuade couples to go for one embryo transfer because I think the kind of thinking with the fertility treatment is that if you get two children, then you don't have to come back and do the treatment again. There is the plus side for them in that sense.
Patients views
Many couples were unaware that twin pregnancies could be risky for mother and babies though most were aware of the risks of higher order pregnancies. Patient information leaflets used in the clinic, perhaps aiming to discourage patients from requesting three embryos, appear to stress the potential complications in triplets rather than twins. I don't think from one to two is a problem. OK I know it is a slightly more hazardous pregnancy but, or more problems with a twin pregnancy but I wouldn't think that one each time was needed at all. (Male 9). When asked if they had been warned of the risks of twin pregnancies, most answered in terms of the chances of conceiving twins. The only thing they really mentioned was the percentage, you know the chances of it happening. No mention of any risks. Risks haven't been mentioned as such. (Female 3). Generally speaking the health risks had not been discussed with them during their consultations with doctors or nurses and some seemed surprised to hear of risks from the researcher. Three patients in health-related professions were aware that twin pregnancies carried more risks for mothers and babies alike and another couple had been informed by a recent television programme.
Most couples were also unaware that the chances of bearing twins after having two embryos replaced varied from woman to woman and were highest among those younger women having their first treatment cycle. Most had considered only the relevance of having a history of twins in their own or their partner's family. Seemingly, all had discussed and accepted the possibility of twins; Well we haven't got children and to have children we are going to have to put up with the risk. If it is twins, fine. If not, one would be fine. (Male 11). They joked that twins would forestall the need for undergoing repeated IVF cycles but did not express a preference for twins. The following interchange is typical: F: We've said two embryos. M: But if it was the case that from that it was twins, we would just accept that ... ultimately we would prefer two children anyway ... if they came at the same time ... F: That's a bonus. (Couple 3). All believed that replacing two embryos increased, and possibly doubled, the chance of becoming pregnant.
Need for RCT of SET
Staff views
Staff debated whether there was an increased incidence of twins now, and were divided on the need for a RCT. One argument was that the problems associated with twins and twin pregnancies were so great that everyone should be given SET as a matter of policy, without the need for a trial. But I think just of late, you know the last few months, we have actually had a few twin pregnancies, the demise of several twin pregnancies and it has made me think. Yeah this really should be, it's the best thing. Go for one embryo transfer and hopefully, not eliminate multiple pregnancies, but certainly limit them quite drastically. (Embryologist 3). Against this was the view that the problems of twin pregnancies had been exaggerated and no trial was necessary: ... I think it is quite difficult to tell them that twin pregnancies show high risk. It isn't so high risk to be honest. OK it is higher risk, but not so much ... it's quite difficult to lie related to the evidence; to tell them that it was suggested to transfer one embryo, because the evidence says something different. (Doctor 3).
Two further arguments against the trial were that the few patients coming to the clinic who were concerned about twins or had religious reservations, should be allowed to have SET and their experience compared with those having two embryos replaced (patient preference). There are some patients, a few, not many and they are concerned about twins. So I think that this group of patients is quite keen to ... because they would accept there is security. (Doctor 3). Alternatively, those most likely to have twins, e.g. younger women or ICSI patients, could be selected and offered SET: Why do the trial? ... I would have thought from the stats that's on our computers we could predict the majority, I mean not all, but a great proportion of all these twins that we are having. And these are the people that we need to counsel further, not put them in any trial. Just say You are young, you are having ICSI or whatever, a high proportion, if we put back two good quality embryos, you are going to have twins. Could you please discuss this? (Embryologist 1). Others thought a trial was pointless because patients had the right to accept the risks and have as many embryos replaced as they wish within reason. I think it is something about choice; that people want choice and if they think that choice is being taken away, however good the reasons for that ... they find that quite difficult and say Well it's my choice to have ... (Midwife 2). It was thought that they would not listen to evidence if presented with it. I think evidence is always a good thing to have ... you can present it, but the difficulty is they never think it is going to happen to them ... people are so desperate really to have a child, they don't necessarily accept it, even though you might present a really good case... (Doctor 2).
All staff mentioned practical problems which made such a trial difficult to mount and possibly unethical. These included convincing people to participate, getting informed consent, blinding staff, particularly embryologists, the amount of counselling required, number of replacement cycles women would undergo, financial arrangements and incentives, and potentially high drop-out rates. It was felt that there would be wastage of embryos in subsequent treatment cycles, less success with frozen embryos, spare embryos left at the end of the trial and a deleterious effect on the unit's success rate. Staff were also very concerned about the psychological effects of such a trial on vulnerable patients.
Many of the staff acknowledged that a RCT would give them much-needed evidence about whether one embryo could eventually produce success rates comparable with two, but without the high incidence of twins. ... certainly on labour ward you see them all the time and you see horrendous complications with multiple pregnancies and I think it is an extremely good idea to do a trial, so that at least then we can say we have done a trial and these are the results. And then go by the results in implementing certain policies. (Doctor 1). They stressed the need to do a proper trial and not one which could be rejected by referees on scientific grounds. One said of patient preference trials ... that is going to bias your study completely because then you are saying you opt for one or two ... there is no point in doing that study because your results are not telling you much ... (Doctor 2); You would need perfect statistics to get you out of a hole. (Embryologist 2).
Nevertheless, they remained uncomfortable with some aspects of a RCT. They thought it would be cruel, deceptive or dishonest to withhold information from patients on how many embryos they were getting at the time of treatment. It was also thought that those whose treatment failed would be angry and resentful towards the staff. However, at the end of a long discussion and consideration of many alternative models, staff, with one dissenter, accepted the need for a trial. But we've discussed that. That came in at the beginning and we went Eek! (Embryologist 1); Yes, but we've talked through more things. (Doctor 2); And we've come back to that. (Midwife 3).
Patients views
After the burden of twin pregnancies had been explained, couples were asked whether they thought the clinic in Aberdeen should be taking steps to reduce the incidence of twins. None thought that it should. All apparently knew of healthy twins and very satisfied parents and thus did not believe this to be a problem sufficient to merit concerted action. M: No, I think the clinic should be advising people as they do you know. F: I think it's the couple's decision at the end of the day. I don't see a huge risk with twins. M: No, it's not a huge risk, but it is an increased risk (Couple 7). However, several respondents asked the interviewer just how high were the risks of having twins who were premature or in poor health. Others thought the sacrifice in terms of success rates was too high. I think the success rate would be the biggest factor wouldn't it? Because with two embryos then there must be a greater success rate because you've got a better chance because there is two. (Female 3).
During the interviews a prospective controlled trial was described where couples are randomly assigned to receive one or two embryos after IVF and respondents were asked for their reactions. Objections to one embryo were that it reduced the chances of success and most felt that because of their age that was unacceptable. Quite a few thought that this was their last hope of conceiving and felt that they had to do all they could to maximize the chances of success. M: It's too much emotion, too much stress. We want this to work and there's not really an option of putting things at risk or cutting your odds. F: I mean I don't want to end up with multiples of more than two really because of the risks involved for both myself and the baby. But I wouldn't want just one embryo put in, giving me just that one chance ... (Couple 2). Age was mentioned by nearly everyone, many saying that this trial might be more acceptable to younger patients or to those with other treatment options available to them. I think if I was younger I would be more accepting of that ... I think I would find that quite hard really, if there were two good eggs and they said Sorry, we're only putting one in. I think I wouldn't like that. (Female 9). One couple who were younger than most said that they would be willing to accept the risk of only having one embryo replaced at a time.
Evidence demonstrating that comparable success rates could be reached after multiple embryo transfers of fresh followed by frozen embryos did not make the prospect of SET any more acceptable. Both men and women expressed concerns about the physical and psychological effects of increased length of treatment associated with SET. Same number in the end? Well as I say it comes down to the fact that the wife is having to go through all that treatment again and injections and all that sort of thing. (Male 11). Several women were worried about the potential carcinogenicity of drugs used during IVF treatment. They also thought that the need for multiple visits to the clinic would create practical difficulties, such as getting time off work. Both men and women said that although they had never experienced it, they thought the treatment would be stressful and had no wish to prolong it.
Finances were not the issue: the idea of having more frozen embryo replacement cycles for the same price did not make the prospect of SET any more acceptable. If you were to say to me pay £2000 and have one at a time or have two and increase the chances of falling pregnant and even if you doubled the price, I would still take double the price, because of the situation we are in; the 3540 year old age group. (Male 2). For those whose treatment was funded by the National Health Service, it was envisaged that treatment would continue for a long time to achieve equivalence (i.e. the replacement of up to six embryos). Those who were funding themselves felt that the cost of IVF was sufficiently large that it should guarantee them the greatest possibility of conception. Though it would not be acceptable to them, a number of couples said that they thought a financial incentive would be necessary to make anyone participate in such a trial. I think it would be important with younger people. I don't think they would be concerned about time but maybe the finances are part of the equation ... I really think that financial pressure would make some people go into the trial. (Female 12).
Randomization
Staff views
There was lively discussion about the possibility of randomizing patients to receive one or two embryos at the time of transfer and blinding patients and/or staff to the number of embryos being replaced. The favourable attitude of most couples towards twins was thought to be a barrier to recruitment. Even if it were possible, withholding information on the number of embryos replaced was deemed unacceptably cruel. It could be justified only in the most rigorous scientific sense, which did not fit with staff's caring role, as is apparent from this interchange:
Some felt it was inappropriate to offer clients what they perceived to be a less than optimum service. There were concerns about the amount of information patients' would have to take in during a short space of time; how able they would be to give informed consent or leave the trial for any reason. Couples whose first cycle had failed were expected to have strong opinions about the trial by the time of the second cycle. It was also felt that some might agree to participate for the wrong (i.e. financial) reasons and then withdraw at the last moment.
Patients views
Confronted with the concept in the abstract, patients found it hard to understand. Having grasped it, they did not like the idea of randomization, but not for the reasons the professionals anticipated. I think your name being picked out of a hat, that's not the best answer, especially if you're paying out money for treatment. Why should you be in a draw, if you know what I mean? (Male 11). They were less worried about the possibility of a single embryo transfer than by what they perceived as the inherent unfairness of randomization. Several women said that they would resent it if they were assigned one embryo and knew of others who had received two. F: I don't think I would be very happy at being selected, not having the choice and I think there should be, either there's a rule and everybody follows it and everybody understands the reasons, or there is a choice and you can make an informed decision. But I wouldn't like to think that somebody else you know got two and I had been randomly assigned to have either one or two. M: I struggle to see what would be the benefit. (Couple 12). Others mentioned the dismay they would feel if treatment failed and they knew they had lost the opportunity to have a second good quality embryo replaced at the same time due to random assignation. They found the prospect of a global SET Unit policy more acceptable. I think I possibly wouldn't, because I would feel disadvantaged I suppose if I was one of the people selected to perhaps just have one egg transfer ... if we got to the stage where the government decided that it is only one egg transfer allowed, then so be it. We would accept it. (Female 6). None found the concept of blinding acceptable. Most felt that they would want to know the number of embryos transferred at the time, if not before, and even soon afterwards was too late.
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Discussion |
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Previous publications have deplored the lack of adequately designed large randomized trials in infertility (Johnson et al., 2003). Involving patients and staff in the design of research studies is an ideal which is gaining currency among researchers and funding institutions (Ghersi, 2002
; Royal College of Obstetricians and Gynaecologists, 2002
), but has yet to become popular in assisted reproduction. To our knowledge this is the first study to use qualitative means in order to explore the attitudes of staff and patients towards a proposed RCT. The focus group mirrored the dynamics of regular staff meetings and provided a non-threatening context for the staff to air their views. However, by its very nature it may have allowed the most vocal to have their say at the expense of the least. The opinions voiced by staff and patients were useful in terms of identifying potential barriers to mounting a SET trial, and were helpful in informing the final trial design.
This study has several limitations. Contrary to the original design, all data from couples were obtained by means of joint interviews. While there was sometimes a tendency for one partner to dominate and the other to concur, couples opinions rarely differed on major issues like randomization or the need for a trial. Couples who differed initially on the risks involved in twin pregnancies quickly reached agreement. This sort of negotiated account is no less valid for being a joint production of the interview situation (Potter and Wetherell, 1994) and probably reflects what would occur if couples were asked to participate in an actual trial of SET. Consecutive sampling resulted in the selection of an older group than would be approached in such a trial. Respondents argued that age was the main deterrent to a trial which could potentially lengthen treatment due to the need for multiple frozen SET. A younger cohort might have been more positive. As couples had limited knowledge of the risks of twins, no conception of a randomized controlled trial, and concerns about costs, these had to be explained by the interviewer. It was made clear to the couples that this person was not the instigator of the proposed trial. Thus, it is unlikely that her identification with the clinic had a major effect on couples views of the proposed trial. Although the exclusion of two senior clinicians from the FGD means that the results cannot be generalized to all grades of staff, it may have encouraged others to freely express their views. Those likely to be more involved with recruiting and randomizing patients had the opportunity to make critical but constructive comments.
Our results support those from previous quantitative studies which have reported that patients are aware of, and accept the risks associated with, twins (Gleicher et al., 1995; Goldfarb et al., 1996
; Murray et al., 2004
). The interview context unveiled more subtle differences of risk perception between staff and patients. We found confusion of risk and chance, with staff believing they were discussing the maternal and perinatal risks of twin pregnancies and patients interpreting this as the chance of having twins. This need for greater clarification in the context of patient information and education has been noted before (Grobman et al., 2001
; Kenyon and Dixon-Woods, 2004
).
Couples responses support the conclusions of previous studies which have reported patients lack of understanding of randomization (Featherstone and Donovan, 2002; Robinson et al., 2004
) and inability to see how it could be justified (Kerr et al., 2004
). Given their lack of enthusiasm about the research question and limited insight into the research methodology, the role of the patients in designing a user friendly trial was not realized. It is possible that as long as patients readily accept the possibility of twins, any potential benefits for patient involvement in a trial aimed at reducing risk will be limited. For those couples who did appreciate the need for the trial, the main barrier to participation appeared to be women's age. Despite the prospect of comparable live birth rates, couples did not feel they had sufficient time to accept multiple frozen embryo transfers as part of a SET policy.
Staff demonstrated some differences along professional lines. Though all prioritized patient wellbeing, embryologists and nurses perceived a distinct conflict in terms of their roles as care providers versus potential researchers. They therefore felt uncomfortable with blinding patients in the context of the proposed trial. All were concerned that any study undertaken should be scientifically sound, and eventually talked themselves back to a position of support for a RCT (which was rejected initially), because they could see no other alternative. Though not asked to agree, they moved towards consensus on how the trial might be mounted. It is possible that this was because the FGD facilitator was known to them; in other circumstances their final position may have been different. While attitudes of staff in different IVF units may vary, our results suggest that, from the point of view of conducting any RCT, it would probably be beneficial to involve staff early in the development of the protocol. Where numbers of participants are sufficiently large, FGD among separate professional groups might provide different perspectives and raise more issues pertinent to them (Kreuger and Casey, 2000). Interviews with those not included in FGD might also demonstrate dissenting views and improve validity.
Despite the general consensus in Europe of the need to minimize iatrogenic multiple pregnancies, this study has highlighted the misgivings among staff and patients in an IVF unit about a proposed trial of SET. It has also identified a lack of understanding and suspicion of crucial factors such as randomization and blinding which contribute to the scientific rigour of a trial. Despite this, staff seemed prepared to play a role in mounting a trial, provided practical difficulties could be overcome. Couples were more negative in their attitudes towards a proposed trial and their input into study design was limited.
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Appendix 1. Interview schedule: IVF patients |
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Appendix 2. Focus group questions: professionals |
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The purpose of today's meeting is to ascertain your views on a proposed multi-centred RCT of replacing one versus two embryos during IVF.
Background: The risks of twin pregnancies for mothers and babies have been highlighted recently, leading to a call for one embryo rather than two or more to be replaced each time. But we do not know how possible this will be, how acceptable to patients and staff, or what will be the clinical or economic costs.
The proposed RCT would address some of these questions. I should like to stress that we believe there are both advantages and disadvantages to replacing one embryo rather than two and we do not have any views on the proposed RCT at this point. We are simply trying to come up with a design which is as acceptable as possible to most of those involved.
Before we start our discussion, there are a couple of house-rules which I should mention.
Confidentiality: Tape-recording will be anonymous and there will be no attempt to identify speakers when listening to the tape or transcribing. But it's obviously not anonymous here and I would ask that you keep what is said confidential. We want people to feel free to express their views without worrying that these will be heard outside these four walls at a later date.
Practicalities: I would ask that you try to wait until one speaker has finished before speaking yourself. We will not be able to hear round the table or on the tape-recorder if more than one person speaks at the same time. If things get heated and everyone is talking at once I will raise my hand and ask you to stop.
Questions
(Opening)
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Acknowledgements |
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References |
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Submitted on June 24, 2004; resubmitted on April 25, 2005; accepted on April 27, 2005.
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