Hum. Reprod. Advance Access originally published online on September 1, 2007
Human Reproduction 2007 22(10):2673-2678; doi:10.1093/humrep/dem173
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Patient attitudes towards twin pregnancies and single embryo transfer—a questionnaire study
1 The Fertility Clinic, Department of Obstetrics and Gynaecology, Aarhus University Hospital, Skejby Sygehus, Brendstrupgaardsvej, DK-8000 Århus N, Denmark 2 Institute of Public Health, Department of Epidemiology, University of Aarhus, DK-8000 Aarhus C, Denmark
3 Correspondence address. Tel: +45 89 102509; Fax: + 45 86 402811; E-mail: astrid.hoejgaard{at}webspeed.dk
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Abstract |
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BACKGROUND: The present trend towards selective single embryo transfer (SET) calls for evaluation of patient attitudes towards twins and how the patients balance advantages and disadvantages of one or two embryos in IVF/ICSI treatment.
METHODS: The study was conducted in a Danish public fertility clinic, where the common practice was double embryo transfer (DET), and the number of reimbursed treatments was limited to three. Referred patients were given oral and written information about the IVF/ICSI treatment including twin probability following DET and the risk of preterm delivery and neonatal complications associated with twins. In order to evaluate patients and partners attitudes towards twins and SET, an anonymous survey was conducted, and 588 couples were invited to participate.
RESULTS: Four hundred and fourteen women (70.4%) and 404 men (68.7%) answered the questionnaire adequately for analysis. About 58.7% preferred having twins to having one child at a time (37.9%). Primary reasons for preferring twins were desire for siblings (23.3%), a positive attitude towards twins (22.5%), and a wish to minimize physical and psychological stress through having as few IVF treatments as possible (19.3%). Economic considerations were not important.
CONCLUSIONS: Obligatory single embryo policy would be in conflict with patient interests and wishes. More carefully prepared information seems to be needed. The challenge consists in balancing clinical considerations with unbiased information on twin pregnancy, respecting patient autonomy and enabling informed decision-making.
Key words: patient attitudes/single embryo transfer/twins/questionnaire
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Introduction |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionAcknowledgementsReferences |
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A high number of multiple births associated with assisted reproductive technologies (ART) (Bergh et al., 1999
; Dhont et al., 1999; Olivennes, 2000; Strömberg et al., 2002; Campbell and Templeton, 2004; Pinborg et al., 2004) has raised concern regarding the number of embryos to be transferred in each cycle. Today, two embryos have become standard in many European countries, and in particular in the Nordic countries. But even with a restriction of two embryos per transfer, the probability of twin pregnancy today remains high at around 25% (Andersen, 2005). In Denmark, it is allowed to transfer a maximum of two fresh embryos, but single embryo transfer (SET) is recommended for patients estimated to have a high chance of pregnancy. Experience from Sweden suggests that SET can be introduced while maintaining acceptable pregnancy rates. In 2004, SET represented 67% of all transfers in Sweden, with an almost unchanged delivery rate of 27% per transfer, whereas the IVF multiple birth rate was reduced to 5.6% (Bergh et al., 2005). When it comes to the acknowledgement of patient wishes, however, the picture seems less clear. Several studies have shown that a large proportion of infertility patients actually desire multiple pregnancies (Pinborg et al., 2003; Child et al., 2004; Ryan et al., 2004). It has been proposed that a proportion of the multiple gestations in IVF is a result of sparse knowledge of neonatal complications among fertility specialists and inadequate information provided to fertility patients (D'Alton, 2004). On the other hand some clinicians question whether the number of complications of multiple pregnancies justifies a SET strategy (van Wely et al., 2006). It appears that neonatal complications cannot outweigh the desire for an ‘instant family' (Child et al., 2004). However, no effect of additional information on the acceptability of SET could be seen in a study by Murray et al. (2004). Thus it is not given that increasing the level of information would change patient attitudes towards twin pregnancies.
It is a common policy in a number of European countries that the public health care system offer a limited number of reimbursed infertility treatment attempts. In Denmark, a maximum of three reimbursed treatment cycles are offered free of charge. Hence, couples may be positively inclined towards double embryo transfer (DET) because it increases the possibility of successful treatment within the treatment offered free of charge by the public health care. Obligatory SET in assisted reproduction would in most countries represent a significant change in ART treatment policy and should be subjected to a meticulous consequence analysis. The cost-effectiveness should be evaluated, but also patient attitudes towards such a new policy should be considered by the decision-makers. This study was performed as part of an extensive health technology assessment study (Ingerslev et al., 2005) and presents a survey examining patient attitude towards SET in a public fertility clinic. The purpose was to:
- evaluate infertile couples' attitudes towards the choice between transfer of one or two embryos, to twinning and their acceptance of the associated neonatal risk;
- elucidate which factors have an impact on the choices of the patient including information and sources of information.
- evaluate how patients balance the acceptability of a hypothetical policy of SET with the option of having more SETs versus the existing policy of three reimbursed DETs.
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Materials and Methods |
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Patient information
The clinic used its standard communication strategies, regarding the question of transferring one or two embryos, consisting of:
- an obligatory advisory meeting for all couples prior to onset of treatment;
- written materials handed to patients (Supplementary material is available at http://humrep.oxfordjournals.org);
- oral consultations with doctors and nurses.
The advisory meeting
An advisory meeting provided practical information about the treatment and background information on causes of infertility, criteria of inclusion for IVF treatment, hormonal treatment, possible side effects and chances of pregnancy (including twin pregnancy). The couples were also informed that smoking and overweight reduce their chances of pregnancy. Complications related to twin pregnancies were not particularly emphasized, whereas triplet pregnancy was described in high-risk terminology. The purpose of the meeting was to provide a summary of the written information, thereby ensuring that all couples had received basic information in at least one medium prior to onset of treatment.
Written information material
All couples received a 43-page booklet describing the treatment process in detail. In addition, it covered topics such as hormonal treatment and possible side effects, embryo freezing, ICSI, etc. The booklet mentioned an increased possibility/risk of twin pregnancy related to transfer of two embryos and stated that ~30% of all IVF pregnancies are twins. It said that twin pregnancies not always pass normally and state the risk of preterm delivery. Couples were encouraged to request transfer of only one embryo if they could not accept the increased risk of twins. The rare possibility of triplets was mentioned, as was the option of fetal reduction.
Consultations with doctors and nurses
Prior to initiating hormonal treatment, the couple was called for a comprehensive consultation with a nurse, where they were informed in detail about the treatment process and other treatment related issues and procedures. Four treatment-related risks were routinely informed to all couples at this consultation. These included ovarian stimulation, other adverse effects from hormonal treatment, risk of infection related to the oocyte retrieval and possibility of multiple pregnancy and its associated risks. Accordingly, all couples were informed that 25% of all pregnancies obtained after DET are twin pregnancies and that the chance of a twin pregnancy is almost 50% in patients under the age of 35 years. Twin pregnancies were described as more burdensome compared to singleton pregnancies, with a doubled risk of malformations. Finally all patients were informed that twin pregnancies have an average gestational length of only 37 weeks and that twins have a higher risk of being small for gestational age. The ultimate cumulative chance of pregnancy after application of all relevant infertility treatment modalities at the time of the study was stated as 75% and for IVF treatment as 60% (three treatment cycles with embryo transfer) and that in the case of SET the chance of pregnancy per embryo transfer would be reduced by ~10%. The nurse routinely also provided information about vaginal ultrasound, issues of smoking and diet, mood fluctuations, chances of pregnancy and the risk that treatment could be unsuccessful. This consultation (at day 21 of menstrual cycle) was the main opportunity for the couple to discuss their concerns face-to-face with staff.
The questionnaire
Both patient and partner in all IVF/ICSI couples referred to the Fertility Clinic at Aarhus University Hospital, Skejby, in September 2004 were approached by a mailed questionnaire. The questionnaire was designed to cover issues of possible importance regarding acceptability or wish for twins. In a pilot study, 12 patients and partners were interviewed after completing the questionnaire. They were invited to comment on the questions and on any subject that they found relevant. It was confirmed that the topics were considered important and final alterations were made. Questionnaires were anonymized. The patients were at all stages of IVF or ICSI treatment. Thus, some were waiting for their first treatment; others had completed one or more treatments with a positive or negative result concerning clinical pregnancy. Participants were informed in writing about the aims of the study that anonymity was guaranteed and that participation was voluntary. The respondents were encouraged to complete the questionnaire without consulting the partner. After 2 weeks, non-responders were contacted again by mail once.
The women received a 56-item questionnaire. The first section in the questionnaire ascertained fertility information, parity, history of infertility and present family structure.
The second section related to the degree to which the respondents desired twin pregnancies and for what reasons. They were also asked to point out their sources of information and to evaluate their satisfaction concerning information on multiple pregnancies on a scale as follows: very satisfactory, satisfactory, fair, unsatisfactory and very unsatisfactory.
Questions in the third section dealt with treatment-related stress, physical pain and side effects on a five-point Likert-type scale in the following way: unacceptably severe, severe, acceptable, mild and none. The importance of a question was measured on a four-point scale: very important, important, not very important and unimportant.
In the fourth section, the respondents were asked about their future preferences for either SET or DET if the number of reimbursed IVF treatments was increased or unlimited.
The fifth section ascertained demographic information; social position was measured in a standardized way including school education and job position.
The male partners received a 41-item questionnaire, leaving out questions on cause and length of infertility, previous pregnancies and births, pain and stress related to hormonal treatment, etc. Otherwise the question and answer categories were identical.
The wordings of the most important questions are presented in the tables.
Approval for the study was obtained from the Danish Data Protection Agency.
Statistics
For bivariate analyses the chi-squared test was used for categorical data. Continuous data following a normal distribution were analysed by t-test and analysis of variance, whereas continuous data not following a normal distribution were analysed by Mann–Whitney U-test and Kruskal–Wallis test. For multivariate analyses of risk factors for dichotomous outcomes (e.g. wish for singleton versus twin pregnancy), logistic regression models were used. Because the attitudes and wishes of two partners cannot be considered independent observations, robust variance estimates taking into account this non-independence were obtained. The Statistical Package for Social Sciences, version 11.0, and Stata version 8 were used for data analyses. A P-value of <0.05 was considered significant.
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Results |
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Of the 588 couples invited, 414 women (70.4%) and 404 men (68.7%) answered the questionnaire adequately for analysis, 169 women and 176 men never returned the questionnaire and 5 women and 8 men returned the questionnaire unanswered. Mean age and cause of infertility among participating women were not significantly different from mean values for all patients referred to the clinic from 2003–2005.
Fertility history, demography
Characteristics of the participants are presented in Table 1.
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Wish for twins
The majority of the patients and their partners preferred having twins (58.7%) to having one child at a time (37.9%), whereas only 3.5% claimed to be indifferent. Within couples, most agreed on their preference (74.6%). Among 60% of the couples who disagreed, the woman preferred twins whereas the man preferred a singleton.
In bivariate analyses, the preference for twins was positively associated with female gender, anovulation, not having endometriosis, not having unexplained infertility, not having biological children and/or step children, being unemployed, number of working hours, short school education and short length of further education. There was no association with age, other causes of infertility, duration of infertility, having adopted children, having children with current partner, parity, previous spontaneous or induced abortions, previous insemination or IVF treatment, previous embryo transfer, having received information, feeling well informed or the extent to which family, friends, colleagues or others were informed about the treatment.
In a multivariate logistic regression model (preference for twins versus a singleton) including the variables that were significantly associated with preference in the bivariate analyses, only the variables in Table 2 were significantly associated with twin preference. For some variables (e.g. school, employment), information was missing for some individuals. Inclusion in the regression model of missing values as a separate category for each variable with missing information did not substantially or significantly change the estimates.
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Among those who preferred to have twins, the primary reasons mentioned by each respondent for wanting twins are shown in Table 3. No significant differences between male and female respondents were found regarding the primary reason for wanting twins (data not shown).
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The primary reason mentioned for wanting one child at a time in the group preferring to have one child at a time are shown in Table 4. There were differences between men and women: men more often pointed out twinning as a risk for the mother (26.4% versus 6.8%, P < 0.001) and for the marriage (5.7% versus 0.8% P = 0.020), whereas women were more concerned about the fetal risks than the men (35.3% versus 15.5%, P < 0.001).
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The above results are well in line with the fact that only 3.8% of the infertile patients would like to be the parent of only one biological child, whereas 52.5% preferred to have two biological children and 43.7% wanted three or more biological children.
Information provided about twins
The information given on twins by the fertility clinic during treatments (through obligatory advisory meeting, written information and oral counselling) was evaluated as fair, satisfactory or very satisfactory by 95% of the respondents. Nevertheless, only 41.6% (340/818) stated that they had received the oral counselling on advantages and disadvantages related to twin pregnancy.
Among those 340 respondents who confirmed having had the oral information on the possible complications of twin pregnancies, 239 (70.3%) were informed by a doctor and 169 (49.7%) by a nurse at the Fertility Clinic, whereas 19 (5.6%) had had the information at the advisory meeting at the clinic. A few patients had the information from another doctor (2.6%), their family (3.2%) or friends (2.4%).
Among the 803 respondents, 620 (77.2%) found counselling on possible risk of twin gestations important. Among the 465 respondents who denied having received any information, 72.7% found information important, and of the 338 respondents who confirmed having had the information, 83.4% found it important (P < 0.001). There was a significant difference of the desire of information between the groups who had had oral counselling compared with those who had not received any oral counselling. Need of (more) information on twin pregnancies was indicated by 32.3% stating that they had received oral counselling on twin pregnancies, whereas this was the case for 70.6% stating that they had not received oral counselling on twin pregnancies (P < 0.001).
To evaluate if the need of information was satisfied otherwise, the patients were asked to point out their sources of information about twins. Furthermore, they were encouraged to indicate from where they would prefer to get information (Table 5). There were no significant differences between women and men (data not shown).
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Of those 236 who had completed a treatment cycle, 83 (35%) had one embryo transferred and 153 (65%) had two embryos transferred. The respondents were asked to point out the reason for the number of embryos replaced (Table 6). Almost all the patients knew they had a choice. A minority of 10.5% was directly advised to have either one or two embryos transferred by the medical staff at the Fertility Clinic. The most common answer was that the decision was their own.
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Treatment related stress and future preferences
The respondents were asked to evaluate stress associated with the treatment in terms of side effects of hormone treatment, pain at oocyte retrieval and general physical and psychological stress. Only 13.6% reported IVF treatment not to be stressful (Table 7). The importance of physical and psychological stress upon the decision between transfer of one or two embryos increased systematically across the level of perceived physical and psychological stress. However, only 7 found the treatment related stress to be unacceptably severe (Mantel–Haenszel
2 test for trend P < 0.001) (Table 7).
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Regarding future preferences of the total population, a large majority of 78.5% (625/796) expressed a wish to have two embryos transferred in a future treatment, whereas only 6.2% (49/796) wanted SET. There was no association with previous history of ART: of those who were at the beginning of their first treatment, 41 of 54 (76%) would opt for DET and 3 (5%) would prefer SET. The preference of twins was not associated with length of infertility or number of completed fertility treatments of any kind. Of the 63 couples who did not succeed in having an embryo transfer in the last treatment and who had not finished treatment, 51 (81%) preferred to have DET in the next treatment. In the group of 139 couples who had had DET and were not at the end of treatments, 107 (77%) would opt for DET in a future treatment if necessary.
Among the 229 respondents who preferred one child at a time, 81.2% (186) planned to have DET in their next treatment cycle. In comparison, 98.6% (413/419) of the respondents who preferred twins would opt for DET in their next treatment cycle.
Number of treatment cycles free of charge and choice between one or two embryos
Being presented with a statement of equal chances of having a childbirth, the respondents were asked about their preference for either four IVF treatments with a SET protocol and 5% chance of twins or three IVF treatments with a DET protocol and 25% chance of twins. A majority of 73.2% (575/785) would prefer the latter option. A similar proportion (73.4%) would opt for DET even if the number of government funded IVF treatments for the first child was unlimited. When the patients were asked to decide between SET and DET, if IVF treatments free of charge were to be a future option for a second child, as many as 67.7% (531/784) respondents still deemed DET as their preferred treatment option.
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Discussion |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionAcknowledgementsReferences |
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The present study revealed that the majority of our infertile couples currently in treatment preferred twins (58.7%) to one child at a time (37.9%) but that a larger majority (78.5%) planned to have two embryos transferred in the next treatment. Accordingly, the preference of DET is not only explained by a wish to have a high success rate and thus avoiding more treatments but reflects a deliberate wish to have twins in the majority of couples. The present proportion of couples preferring twins seems high. Other studies have shown that the proportion of fertility patients preferring twins were 20.3% (Ryan et al., 2004), 38.9% (Child et al., 2004
), 14% (Kalra et al., 2003) and 32% (Murray et al., 2004), respectively. In the latter study, however, 93% did not mind having twins. The high number of Danish patients wanting twins seems to be a robust observation, as a national survey among IVF/ICSI mothers showed that 84.7% of twin mothers and 62.3% of singleton mothers preferred to have twins (Pinborg et al., 2003).
Preference of DET is in agreement with present practice in most public and private fertility clinics in Denmark. As the public clinics are similar and as patients are normally referred by their general practitioner to the nearest public clinic, it seems to be unlikely that patients in favour of DET would select our clinic. However, it cannot be ruled out that highly motivated staff members focused on obtaining high pregnancy rates might subconsciously balance their counselling towards DET. The acceptance of an existing policy is, however, well known among fertility patients (Murray et al., 2004) and was also seen in an earlier study in our clinic concerning the preference of one of two different treatment protocols (Højgaard et al., 2001). Our finding that the wish to have twins was not associated with age is in line with Pinborg's (2003) Danish national survey—but in contrast to the findings of Child et al. (2004). The primary reasons for wishing twins were a desire for eventual children to have siblings, an unspecific positive attitude towards twins and the wish for few IVF treatment cycles. A single child was preferred (42%) due to the risk for the child or mother.
Economic motives for twin preferences seemed of less importance in the present study. In Denmark, three IVF/ICSI embryo transfers are free of charge. Further, treatments in case no pregnancy is obtained, or treatments to achieve a second child must take place in a private clinic at the couples own expense. Nevertheless only a few stated that they could not pay for a second child in a private clinic. In contrast, Kalra et al., (2003) suggested that treatment cost could be one of the hidden factors explaining the desire for twins. The fact in the present study that only a minority would opt for SET if combined with four reimbursed embryo transfers or even an unlimited number of treatments, or if treatments for a second child was reimbursed, strongly suggest that economic considerations play a minimal role.
The information given on twins was evaluated as very satisfactory, satisfactory or fair by nearly all couples, although only 44.8% said they obtained their knowledge from oral counselling in the clinic. Only 12% stated that their previous decision(s) on number of embryos transferred was based on advice from the fertility clinic, whereas one-third described the decision as their own choice. Nearly all knew they had a choice. In spite of the fact that 55.5% of the couples had found information in the media and the Internet, only 13.6% found these sources preferable. Very few had actively sought information by using patient associations. It seems that an important source of information is case-based, by knowing families with twins. Still, most preferred personal counselling at the Fertility Clinic. It is difficult to evaluate to what extent the counselling about twins was sufficient in the present study, but the general impression was that more specific and organized information obtained through person to person counselling was demanded. The question is, however, whether information would change the wish to have twins. In the analyses in the present study, there was no association between opting for twins and having received information and feeling well informed. Other studies have shown that infertility patients seem to be rather unaffected by perceptions of a high risk associated with twins (Kalra et al., 2003). Furthermore, attitudes towards elective SET seemed independent of methods of information provision in a randomized study by Murray et al. (2004). Perception of risk among patients rather appears to be strongly dependent upon wording. A review study of acceptance of prenatal examinations (Dahl et al., 2006) showed that women regard risk expressed as proportions or relative risk ratios as more worrying than when expressed as percentages, number needed to treat or as absolute risk reduction. The same study showed that the framing of a risk estimate in a positive direction (chance vs. risk) makes the outcome sound significantly less likely and worrying. An attempted neutral or even positive wording with emphasis on chances rather than risks could inspire future guidelines for written and oral information regarding twin pregnancies. The challenge consists in balancing clinical considerations with unbiased information on the potential consequences of twin pregnancy in ways that respect patient autonomy and empowers informed decision-making. In our clinic, the results of the study in combination with political focus on the issue of twins have resulted in an explicit recommendation of SET in the first treatment cycle.
The results of the present study revealed a strong desire to have at least two children. This translated into a wish to have twins among couples undergoing fertility treatment. Many associated positive values with twins. The study also showed that experienced physical and psychological stress associated with the treatment strongly influenced the preference for twins. Also, patients did not focus on cumulative chances of pregnancy following a sequence of treatment cycles since more (reimbursed) treatments to compensate for SET were not attractive. The study indicates that an obligatory single embryo policy would be in conflict with patient interests and wishes. More carefully prepared information on twin pregnancy seems to be needed. But the most appropriate mode of presentation remains open for debate, and it remains to be evaluated how much such information may affect patient attitudes towards SET.
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Acknowledgements |
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We would like to acknowledge the volunteering pilot couples, the patients participating in the study and the staff at the Fertility Clinic. Jens Seeberg is acknowledged for supporting the development of the questionnaire.
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References |
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Submitted on March 13, 2007; resubmitted on May 9, 2007; accepted on May 11, 2007.
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A. Hojgaard, L.D. Ottosen, U.S. Kesmodel, and H.J. Ingerslev Reply: Patient attitudes towards twin pregnancies and SET: a questionnaire study Hum. Reprod., May 1, 2008; 23(5): 1233 - 1234. [Full Text] [PDF]
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