Gamete and embryo donation for research: what might shape the willingness to donate among gamete donors and recipients?

Abstract

Purpose

Research using gametes and embryos donated by reproductive and third-party donors contributed to substantial, albeit contentious achievements. The views of gamete donors and recipients on donation for research and the underpinning role of attitudes towards research have been seldom explored and are yet to be incorporated into ethical, legal, and regulatory landscapes. From a cultural standpoint, this study adapts and explores psychometric properties of the Portuguese version of the Research Attitudes Questionnaire (RAQ), and analyzes the willingness of gamete donors and recipients to donate gametes and embryos for research and its association with sociodemographic, reproductive characteristics, and attitudes towards research.

Methods

Between July 2017 and June 2018, 71 donors and 165 recipients completed a self-administered questionnaire at the Portuguese Public Bank of Gametes. Willingness to donate and attitudes towards research were measured with a 5-point Likert scale. RAQ psychometric characteristics were explored.

Results

Two RAQ components were identified: “trustworthiness of research” and “critical perspective”. Most participants were willing to donate gametes and embryos: donors more willing to donate gametes and male recipients more willing to donate gametes and embryos. Higher RAQ scores, indicating a more positive attitude towards research, were observed on the component “trustworthiness of research” among those willing to donate gametes and embryos and on the component “critical perspective” among those willing to donate embryos.

Conclusion

These findings help foster inclusivity, diversity, and responsiveness of research and call for upstream engagement of male and female gamete donors and recipients, promoting a trustworthy, anticipatory, democratic, and people-centered approach to policies, regulations, and practices in human gamete and embryo research.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10815-022-02569-y.

Introduction

Research using donated human gametes and embryos has recently contributed to substantial scientific achievements at the interface of assisted reproduction and genetics. A better understanding of infertility and the development of mitochondrial replacement techniques (MRT) or human germline genome editing technologies (HGGE) are some examples [1, 2]. While the demand for donated embryos has already grown, the need to refine, improve, and assess the effectiveness and safety of these and other achievements may result in greater needs for donated oocytes and sperm [3–5]. However, a wide range of scientific projects has been considered contentious and has raised additional ethical, legal, regulatory, and social issues [5, 6]. This has led to more calls for wide dialogue and stakeholder engagement to help inform inclusive, democratic, and anticipatory policies, regulations, and practices over research and clinical application of these technologies [3, 7–10].

Oocyte and sperm donors may be recruited purposively for specific biobanks or research projects [11–13], but gametes and embryos are usually donated for scientific purposes by reproductive and third-party donors [14]. These include individuals who donate oocytes, sperm, or embryos for research, which were otherwise intended for reproductive purposes but are no longer needed, storable, eligible, or compatible [15, 16] or as part of fertility assessment or “egg sharing for research” protocols [13, 17–19]. Although the use of assisted reproductive technologies (ART) is increasingly relying on gamete donation [20], literature has focused on the willingness to donate embryos for research among couples undergoing homologous in vitro fertilization (IVF) treatments [21]. Gamete donation for research has been mainly studied among females resorting to these treatments and potential oocyte or sperm donors (e.g., women attending appointments at a hospital department of obstetrics and gynecology, university students) [22–25]. The views of gamete donors and recipients towards donation of gametes and embryos created by gamete donation have been seldom explored [15, 24, 26–31], which has possibly hindered the inclusion of their perspectives into ethical, legal, and regulatory landscapes [3, 10].

Despite increased recognition of the importance of attitudes towards research, namely trust, in the decision to participate in medical research, particularly among seldom-heard groups [32–35], the analysis of the factors behind the willingness to donate gametes and embryos has focused on the role of sociodemographic and reproductive characteristics in embryo donation and has resulted in inconsistent evidence [21]. Trust in scientific and medical institutions was acknowledged to influence the decision-making process concerning embryo donation [21], but attitudes towards scientific principles and methods [36] have been marginally explored. Previous studies also analyzed specific or compared distinct purposes and outcomes (e.g., research on therapeutic interventions, infertility, or stem cells [23–25, 29]) and considered the importance attributed to embryo research [37]. Limited attention has been given to the systematic evaluation of attitudes towards research using standardized instruments such as the Research Attitudes Questionnaire (RAQ) and their role in the willingness to donate gametes and embryos for scientific purposes, as in the donation of other human bodily material to biobanks [38, 39]. The RAQ has the advantage of being a brief instrument that measures general attitudes both towards medical research and researchers and whose scores have already been associated with willingness to donate distinct bodily material for scientific purposes [40], considering different moral concerns [38] and the use of blanket consent [39].

Therefore, we aim to culturally adapt and explore the psychometric properties of the Portuguese version of the RAQ, and to analyze the willingness of donors and recipients to donate gametes and embryos for research purposes. We also intend to study its association with sociodemographic and reproductive characteristics, as well as with attitudes towards research.

Materials and methods

Study design

An observational cross-sectional study was conducted at the Portuguese Public Bank of Gametes, located in Porto, in the northern region of Portugal. Between July 2017 and June 2018, gamete donors and recipients who attended at least one medical appointment were consecutively informed of the study and given an informative leaflet by a health professional at the end of each appointment. A researcher, available to answer their questions and doubts, subsequently invited donors and recipients to participate. Couples were asked to take part individually. Of the 329 potential participants invited, 251 (76.3%) agreed to participate: 72 donors and 179 recipients. Nonparticipation was due to lack of time (n = 39), unwillingness (n = 20), unavailability (n = 8), and unmentioned reasons (n = 11). Those who agreed to take part were accompanied to a private setting at the healthcare service, where they read and signed an informed consent and completed a self-administered structured questionnaire [30].

This questionnaire, developed to explore the views of distinct stakeholders on ethical, legal, and social issues associated with gamete donation, included questions on sociodemographic and reproductive characteristics, namely, age, relationship with gamete donation, sex, educational level, marital status, country of origin, working status, perceived household income adequacy, subjective social class, parental status, previous experience of donation/heterologous ART treatment, and type of gametes received. Willingness to donate gametes and embryos for research was evaluated using a 5-point Likert scale ranging from (0) “very unwilling” to (4) “very willing” to the following questions: “If you had all necessary conditions to donate gametes, how willing would you be to donate gametes for scientific research?” and “Imagine that you were a recipient of donated gametes and that cryopreserved embryos remained from that treatment. How willing would you be to donate embryos for scientific research?”. The answers to these questions were recoded into a dichotomous variable: “willing” (3 or 4, including those who reported to be willing and very willing) and “other” (0, 1, or 2, including those who reported to be unwilling or unsure).

Additionally, the RAQ, developed to predict participation in research, was used to measure attitudes towards medical research [41, 42]. Participants are requested to report their level of agreement with 11 statements using a 5-point Likert scale ranging from (1) “strongly disagree” to (5) “strongly agree”. Four items are reverse coded, and the total score ranges from 11 to 55, with higher scores representing a more positive attitude towards research. Permission to use and translate the RAQ was granted by the leading original author, as this was, to our knowledge, its first linguistic adaptation to Portuguese. RAQ was translated by two native Portuguese researchers with an interdisciplinary background that includes science and technology studies (SPS and SS). Two independent native speakers back-translated the Portuguese version into American English, in order to compare it with the original text and guarantee its equivalence. Minor discrepancies between these versions were consensually solved, and the Portuguese version was adjusted. An interdisciplinary team of public health researchers with expertise in social and biomedical sciences evaluated the comprehensibility and the interpretation of the items, ensuring face validity. The original and the Portuguese versions of the RAQ are shown in Supplementary information 1.

Statistical analysis

Missing values were assumed to be at random. Participants with missing values in five or more RAQ items were excluded from the exploratory assessment of psychometric characteristics. Prior to data analysis, the scores of items 2, 5, 7, and 10 were reversed. Principal component analysis (PCA) with oblimin rotation was conducted to assess dimensionality. The number of relevant components to be retained was determined both by a visual inspection of the scree plot — using Cattell’s criterion — and by analysis of the eigenvalues using Kaiser’s criterion [43]. Pairwise exclusion of cases with missing values (seven participants in one RAQ item and one in two items) was used to include all available data. It was established that items with factor loadings below 0.40 in all components or with cross-loadings would be removed [44].

The applicability of the PCA was assessed with the Kaiser–Meyer–Olkin (KMO) measure of sampling adequacy, as well as with Bartlett’s test, in order to assess whether the correlation matrix significantly differed from the identity matrix. In the KMO statistic, a value between 0.70 and 0.80 is considered good; in Bartlett’s test, a p-value < 0.05 indicates that at least one correlation between items is significantly different from zero [43]. Cronbach’s alpha (α) and McDonald’s omega total coefficients (ω_t) were used as measures of indirect reliability: values of α and ω_t between 0.60 and 0.70 were considered acceptable, while values above 0.70 indicate good internal consistency [45, 46]. McDonald’s omega hierarchical (ω_h) was used to evaluate unidimensionality [47]. Missing values, per participant, in RAQ items, were replaced by the average score in the remaining items of each RAQ component identified in the PCA. A total score (i.e., the sum of the individual item scores) was then computed for each component. Participants with missing data regarding willingness to donate gametes and embryos have been excluded from the analysis of the association of these two outcomes with sociodemographic and reproductive characteristics, as well as with attitudes towards research.

Median and percentiles (P25–P75) are presented for the continuous variable “age”, counts and proportions for categorical variables, and mean (M) and standard deviation (SD) for RAQ scores per item and component. Because the Cochran-Mantel–Haenszel test has shown a gendered distinction regarding the willingness of donors and recipients to donate, descriptive statistics of the willingness to donate gametes and embryos according to sex are presented separately for donors and recipients. Comparisons were performed with Mann–Whitney U, chi-square (or Fisher’s exact test when appropriate), and Student’s t-tests, with a p-value < 0.05 indicating statistical significance. Statistical analysis was performed using SPSS version 26 (Armonk, NY, USA) and R version 4.0.3 (R Core team, Vienna, Austria), including the psych package for R, version 2.0.9 [48].

Results

Psychometric characteristics of RAQ’s Portuguese version

Mean scores per RAQ item ranged between 1.68 (SD = 0.82) and 4.51 (SD = 0.69) (Table 1), taking into account the 248 participants without missing values in five or more RAQ items. Analysis of the scree plot and of eigenvalues indicated that two components should be retained (Table 2). Item 7 had a high negative loading in component 1 and seemed to also have loadings in component 2, which has resulted in its removal. Component 1 is constituted by items 1, 3, 4, 6, 8, 9, and 11 (29.5% of total variance) and component 2 by items 2, 5, and 10 (13.3% of total variance) (Table 2). McDonald’s omega hierarchical coefficient (ω_h = 0.37) suggests these two components do not measure a single construct and should be analyzed separately. Internal consistency of components 1 and 2 (ω_t = 0.80; α = 0.70 and 0.60) is considered good and acceptable. Component 1, “trustworthiness of research”, includes seven items illustrating trustworthy features of research and researchers, beliefs and expectations of participation in research, and its benefits. Its score ranges between 7 and 35, with higher scores indicating a more positive attitude towards research. Component 2, “critical perspective”, includes three items focused on concerns over safety of research (e.g., of harms outweighing its benefits) and motivations of researchers to pursue individual interests rather than shared ones. Its score ranges between 3 and 15, with higher scores representing a less critical and thus more positive attitude towards research.

Table 1.

Descriptive statistics of the items composing the Portuguese version of the Research Attitudes Questionnaire (RAQ)

Items	n	Mean (SD)	Corrected item-total correlation	Cronbach’s alpha if item deleted
1. I have a positive view about medical research in general	248	4.44 (0.74)	0.35	0.63
2. Medical researchers are mainly motivated by personal gaina	246	3.66 (1.33)	0.27	0.65
3. Medical researchers can be trusted to protect the interests of people who take part in their studies	248	4.33 (0.77)	0.33	0.63
4. We all have some responsibility to help others by volunteering for medical research	247	4.35 (0.76)	0.34	0.63
5. Modern science does more harm than gooda	245	3.99 (1.09)	0.50	0.59
6. Society needs to devote more resources to medical research	247	4.40 (0.74)	0.29	0.63
7. Medical research needs to be closely regulated in order to prevent harm to research participantsa	247	1.68 (0.82)	− 0.15	0.70
8. Participating in medical research is generally safe	247	3.99 (0.84)	0.39	0.62
9. If I volunteer for medical research, I know my personal information will be kept private and confidential	248	4.51 (0.69)	0.36	0.63
10. A lot of emphasis on medical research and scientific progress is likely to harm research volunteersa	248	3.52 (1.23)	0.46	0.60
11. Medical research will find cures for many major diseases during my lifetime	248	4.26 (0.82)	0.31	0.63
			Cronbach’s alpha	0.65

n, number of observations. SD, standard deviation. ^aItems with reversed score

Table 2.

Summary of the principal component analysis (with oblimin rotation) of the Portuguese version of the Research Attitudes Questionnaire (RAQ)

	11-item RAQ version (n = 248)		10-item RAQ version (n = 248)
Items	Component 1	Component 2	Component 1	Component 2
1. I have a positive view about medical research in general	0.49	0.13	0.51	0.09
2. Medical researchers are mainly motivated by personal gaina	− 0.11	0.77	− 0.18	0.82
3. Medical researchers can be trusted to protect the interests of people who take part in their studies	0.60	0.00	0.66	− 0.09
4. We all have some responsibility to help others by volunteering for medical research	0.68	− 0.06	0.71	− 0.12
5. Modern science does more harm than gooda	0.24	0.68	0.18	0.70
6. Society needs to devote more resources to medical research	0.59	− 0.04	0.59	− 0.06
7. Medical research needs to be closely regulated in order to prevent harm to research participantsa	− 0.52	0.34
8. Participating in medical research is generally safe	0.61	0.11	0.62	0.08
9. If I volunteer for medical research, I know my personal information will be kept private and confidential	0.57	0.11	0.56	0.10
10. A lot of emphasis on medical research and scientific progress is likely to harm research volunteersa	0.19	0.66	0.15	0.67
11. Medical research will find cures for many major diseases during my lifetime	0.45	0.13	0.47	0.08
Eigenvaluesb	3.02	1.42	2.95	1.33
% total varianceb	27.5	13.0	29.5	13.3
Omega hierarchical coefficient (ωh)	0.33		0.37
Cronbach’s alpha coefficient (α)	0.57	0.60	0.70	0.60
Omega total coefficient (ωt)	0.80		0.80
Inter-factor correlation
Component 1	1.00	0.19	1.00	0.28
Component 2	0.19	1.00	0.28	1.00
KMO	0.80		0.79
Bartlett’s test	p < 0.001		p < 0.001

^aItems with reversed score. ^bValues before oblimin rotation

Willingness to donate gametes and embryos for research

Data gathered from 236 participants about their willingness to donate gametes and embryos show a median age of 35 (Table 3). Most were involved in third-party reproduction as recipients (69.9%) and were female (62.3%). More than half (51.5%) attained ≤ 12 years of education. The majority were married/living with a partner (69.1%), born in Portugal (88.9%), employed (80.7%), perceived their household income as sufficient (70.6%), reported belonging to a low/middle-low social class (71.6%), were childless (87.7%), had no previous experience as donors or recipients (73.7%), and, as recipients, were enrolled in a treatment involving donated sperm (60.1%).

Table 3.

Willingness to donate gametes and embryos for research purposes according to the characteristics of participants

	Total	Willingness to donate gametes for research			Willingness to donate embryos for research
	(n = 236)	Willing (n = 170)	Other (n = 66)	p-value	Willing (n = 160)	Other (n = 76)	p-value
Overall		170 (72.0)	66 (28.0)		160 (67.8)	76 (32.2)
Age, median (P25–75)	35.0 (28–38)	34.5 (28–38)	35.0 (29–39)	0.540	35.0 (29–38)	33.0 (27–37)	0.140
Relationship with gamete donation, n (%)
Donor	71	59 (83.1)	12 (16.9)	0.013	53 (74.6)	18 (25.4)	0.140
Recipient	165	111 (67.3)	54 (32.7)		107 (64.8)	58 (35.2)
Sex (considering only donors), n (%)
Female	46	39 (84.8)	7 (15.2)	0.742*	34 (73.9)	12 (26.1)	0.847
Male	25	20 (80.0)	5 (20.0)		19 (76.0)	6 (24.0)
Sex (considering only recipients), n (%)
Female	101	61 (60.4)	40 (39.6)	0.018	56 (55.4)	45 (44.6)	0.001
Male	64	50 (78.1)	14 (21.9)		51 (79.7)	13 (20.3)
Educational level, n (%)§a
≤ 12 years	119	91 (76.5)	28 (23.5)	0.144	80 (67.2)	39 (32.8)	0.804
> 12 years	112	76 (67.9)	36 (32.1)		77 (68.8)	35 (31.3)
Marital status, n (%)
Married/living with partner	163	113 (69.3)	50 (30.7)	0.166	111 (68.1)	52 (31.9)	0.882
Single/divorced	73	57 (78.1)	16 (21.9)		49 (67.1)	24 (32.9)
Country of origin, n (%)§
Portugal	209	155 (74.2)	54 (25.8)	0.077	145 (69.4)	64 (30.6)	0.228
Otherb	26	15 (57.7)	11 (42.3)		15 (57.7)	11 (42.3)
Working status, n (%)§
Employed	188	137 (72.9)	51 (27.1)	0.812	131 (69.7)	57 (30.3)	0.212
Otherc	45	32 (71.1)	13 (28.9)		27 (60.0)	18 (40.0)
Perceived household income adequacy, n (%)§d
Insufficient	69	48 (69.6)	21 (30.4)	0.540	42 (60.9)	27 (39.1)	0.126
Sufficient	166	122 (73.5)	44 (26.5)		118 (71.1)	48 (28.9)
Subjective social class, n (%)§e
Low/middle-low	136	104 (76.5)	32 (23.5)	0.540	95 (69.9)	41 (30.1)	0.747
High/middle-high	54	39 (72.2)	15 (27.8)		39 (72.2)	15 (27.8)
Parental status, n (%)§
Children	29	20 (69.0)	9 (31.0)	0.664	21 (72.4)	8 (27.6)	0.593
No children	206	150 (72.8)	56 (27.2)		139 (67.5)	67 (32.5)
Previous experience on donation/treatment, n (%)
Yes	62	41 (66.1)	21 (33.9)	0.228	40 (64.5)	22 (35.5)	0.520
No	174	129 (74.1)	45 (25.9)		120 (69.0)	54 (31.0)
Type of gametes received (only recipients), n (%)§
Oocytes	65	46 (70.8)	19 (29.2)	0.466	44 (67.7)	21 (32.3)	0.562
Sperm	98	64 (65.3)	34 (34.7)		62 (63.3)	36 (36.7)
RAQ component 1 score (7 items), mean (SD)	30.3 (3.1)	30.7 (3.0)	29.3 (3.2)	0.002	30.9 (2.9)	29.0 (3.3)	< 0.001
RAQ component 2 score (3 items), mean (SD)	11.3 (2.7)	11.4 (2.7)	10.8 (2.6)	0.137	11.5 (2.7)	10.7 (2.8)	0.048

Proportions may not add up to 100% due to rounding. SD, standard deviation. *Fisher’s exact test. §In these variables, the total does not add up to 236 or 165 due to missing values. ^aEducational level was assessed using a multiple-choice question with 10 answer categories available. The answers were recoded into a dichotomous variable: ≤ 12 and > 12 years of education. ^bAngola, Australia, Brazil, Cape Verde, France, Luxembourg, Russia, the USA, or Venezuela. ^cStudent, unemployed, or retired. ^dPerceived household income adequacy was assessed using a multiple-choice question with four answer categories available. The answers were recoded into a dichotomous variable: insufficient (reported subjective economic hardship — that is, insufficient income or caution with expenses) and sufficient (household income enough to make ends meet or comfortable). ^eSubjective social class was assessed using a multiple-choice question with six answer categories available. The answers were recoded into a dichotomous variable: low/middle-low class and high/middle-high class, with the answers “none of the above” and “prefer not to say” being excluded of the analysis

Most participants were willing to donate gametes (72%) and embryos (67.8%) for research purposes. Compared with recipients, donors were willing to donate gametes more frequently (83.1% vs. 67.3%). Male recipients reported to be willing to donate gametes and embryos more frequently (78.1% and 79.7%) than female recipients (60.4% and 55.4%). Higher mean scores in the RAQ “trustworthiness of research” component were observed among those willing to donate gametes (M = 30.7, SD = 3.0 vs. M = 29.3, SD = 3.2) and embryos for research (M = 30.9, SD = 2.9 vs. M = 29.0, SD = 3.3), while higher mean scores in the “critical perspective” component were observed among those willing to donate embryos (M = 11.5, SD = 2.7 vs. M = 10.7, SD = 2.8).

Compared with those unwilling or unsure, participants willing to donate gametes and embryos tended to strongly agree with items included in the RAQ “trustworthiness of research” component (Fig. 1). While most viewed medical research as positive (60.6% and 63.8% strongly agree with item 1) and trustworthy regarding privacy and confidentiality (60.6% and 62.5% strongly agree with item 9), fewer participants perceived medical research as safe (35.9% and 34.4% strongly agree with item 8). These participants also tended to disagree with items included in the “critical perspective” component, considering how these were originally formulated. Disagreement was low in respect of reservations and concerns towards potential harms of emphasis on medical research and scientific progress (33.5% and 34.4% strongly disagree with item 10).

Fig. 1.

Level of agreement of participants with items of the Research Attitudes Questionnaire (RAQ) considering their willingness to donate gametes and embryos for scientific purposes. The RAQ measures attitudes towards research and researchers by including items illustrating trustworthy features of research and researchers, beliefs and expectations of participation in research and its benefits (“trustworthiness of research” component), and concerns over safety of research and motivations of researchers (“critical perspective” component). Level of agreement (%) ranges between strongly agree to strongly disagree. In each RAQ item, within willingness to donate gametes (not striped) and embryos (striped), the left bar illustrates the level of agreement of participants who reported to be willing to donate (“willing”), and the right bar illustrates the level of agreement of participants who reported to be unwilling or unsure to donate (“other”)

Among those willing to donate gametes, the majority agreed that research is positive and safe (“trustworthiness of research” component, item 1: 94.1% vs. 83.1% and item 8: 73.0% vs. 61.6%). Disagreement was high with the item about potential harms of research outweighing its benefits (“critical perspective” component, item 5: 74.7% vs. 56.4%). Among those willing to donate embryos, agreement was strong concerning the overall view of research as positive, the perception of researchers as trustworthy to protect participants beyond self-interest, the need for solidarity and societal support, and the belief in the benefits of research (“trustworthiness of research” component, item 1: 91.9% vs. 89.3%; item 3: 90.0% vs. 86.7%; item 4: 90.0% vs. 76.0%; item 6: 89.4% vs. 88.0%; and item 11: 87.6% vs. 76.0%). These participants also strongly disagree with item 5 of the “critical perspective” component (75.0% vs. 58.4%).

Discussion

Our results demonstrate that those involved in third-party reproduction, particularly donors and male recipients, are willing to donate gametes and embryos for scientific purposes. A more positive attitude towards research, as measured by the RAQ “trustworthiness of research” component, was observed among those willing to donate gametes and embryos. Scores in the RAQ “critical perspective” component, representing a less critical and thus more positive attitude towards research, were higher among those willing to donate embryos.

The proportion of participants willing to donate gametes and embryos created by gamete donation (72% and 67.8%) is similar, despite gametes and embryos having distinct legal and regulatory frameworks [20, 49] and being differentiated by those involved in ART [50, 51]. Although the proportion of gamete donors and recipients willing to donate embryos for research is higher than the proportion of users of ART reported in most studies [21], it is lower when compared with a previous Portuguese study with couples undergoing homologous IVF treatments [37]. And while sociocultural differences between countries should be acknowledged, it appears that donors and recipients, when compared with users of homologous procedures, may be more willing to donate embryos for reproductive purposes than for research. This has been observed by a retrospective study in the United States of America (USA) with oocyte recipients [15] and by a more recent French study, according to which recipients either of oocytes or sperm were 10 times more likely to donate embryos to other couples [26]. However, the current transition towards non-anonymous donation for reproductive purposes in Portugal might impact on the willingness of donors and recipients to donate gametes and embryos for research, as they have reported a strong preference for anonymity before the decision of the Constitutional Court that enacted this legal and regulatory change [52].

Altruistic motivations have been reported as one of the main reasons for donation of oocytes and sperm for third-party reproduction [53] and also seem to be behind the donation of other bodily material for scientific purposes [54, 55], which might explain donors being more willing to donate gametes for research than recipients. Perhaps for some recipients it may also have been difficult to imagine that they would have the necessary conditions to donate their gametes. Although specific schemes of donation for research were developed for female users of ART [19], and while previous studies [22–24] and calls for engagement in the discussion about MRT and HGGE [3, 10] have focused on female donors, our results reinforce the need to include the perspectives of male donors and recipients. Future studies should explore the reasoning behind distinct gendered positions towards gamete and embryo donation for research among donors and recipients.

A more positive attitude towards research, as measured by the “trustworthiness of research” component of RAQ’s Portuguese version, was observed among those willing to donate gametes and embryos for scientific purposes. The “critical perspective” component was also relevant among those willing to donate embryos. Previous studies have explored aspects such as distinct moral concerns [38], the use of blanket consent [39], or the purposes, the potential outcomes [23–25, 29], and the perceived relevance [37] of gamete and embryo research. Yet, our results suggest that overall attitudes towards research may be the underlying reason for the willingness to donate distinct bodily material for scientific purposes, regardless of its differences [49, 51]. Further research is needed regarding values and beliefs associated with each type of bodily material, as the moral status of sperm, oocytes [23], and embryos [21] or embryo representations [26] have also been associated with willingness to donate gametes and embryos. Since information on research purposes should be provided during informed consent processes [14, 56] and the engagement of research participants in decision-making about the use of donated bodily material is being increasingly advocated [57], an in-depth understanding of the views of donors and recipients towards distinct consent processes and research priorities and purposes would also help to raise awareness of potential misconceptions about gamete and embryo research [9, 58] and anticipate their preferences [5].

Respect for privacy and confidentiality (RAQ “trustworthiness of research” component, item 9) was perceived as one of the most trustworthy features of participation in research, notwithstanding researchers and ethicists voicing growing concerns over privacy and confidentiality associated with the sequencing and the storage of genomic data in gamete and embryo research [5, 56]. Gamete donors and recipients who took part in this study might not be aware of these concerns, hence the need to inform them in the consent process, as also recommended by international ethical guidelines [14, 56]. In a previous study using a version equivalent to RAQ “trustworthiness of research” component, the best predictor of the willingness to participate in a clinical trial was the perception of research as safe [59]. Although gamete donors and recipients tended to perceive safety as the least trustworthy characteristic of research participation, those willing to donate gametes for scientific purposes viewed medical research as positive, safe, and potentially harmless. Those willing to donate embryos also tended to perceive researchers as trustworthy to protect participants beyond self-interest and to believe in the need for solidarity and societal support and in the benefits of research. These findings align with the previously observed importance of societal benefits as one of the main reasons in favor of embryo donation for research [21]. This sustains the need to further explore motivations for gamete and embryo donation and the potential role of altruistic- and solidarity-based willingness to donate [57], in different sociocultural settings and under distinct legal and regulatory frameworks on anonymity/non-anonymity. To our knowledge, this study is the first to simultaneously analyze the willingness of male and female gamete donors and recipients to donate, to use a Portuguese cultural and linguistic adaptation of RAQ, and to use it in the context of gamete and embryo donation for research. Our results might be overestimated as we measured hypothetical and not effective willingness to donate. We also evaluated donors and recipients who accepted to participate in this cross-sectional study and thus might have a more positive view of research. Future studies, particularly with longitudinal designs, should examine if previous participation in research, diagnosis of infertility, stage, and success of donation/treatment(s) might impact the attitudes towards research and the willingness to donate.

Item 7, which states that “Medical research needs to be closely regulated to prevent harm to research participants”, was removed from RAQ’s Portuguese version. Despite the common perception of regulation and oversight as the answer to concerns about trust [33], donors and recipients might have a positive attitude towards research while still considering that it needs to be closely regulated. Our results suggest a 10-item version with two components: a seven-item component equivalent to a previously recommended version [41] and a three-item component providing additional information on reservations and concerns. An analysis of public attitudes towards science and technology in Canada, the USA, the European Union, and Japan found that beliefs in their benefits and concerns about their negative impact were separate factors and were not mutually exclusive [60], which might explain their coexistence. Internal consistency of the seven-item component is considered good, while the three-item version needs improvement, which might have been due to the limited sample size and number of items [43].

Race and ethnicity have been linked with the willingness to participate in research and to donate embryos for scientific purposes [27, 61], with the acceptance of embryonic research [62], and with attitudes towards research [63, 64], but these variables were not addressed in our study. Data on religion were also not collected, despite previous association with acceptance of embryonic research [62] and with willingness to donate embryos for scientific purposes among Portuguese male users of homologous IVF treatments [37]. Further research is needed to clarify the role of these variables.

The number of participants involved in third-party reproduction as recipients is higher than the number of those involved as donors. In Portugal, access to ART was expanded to all women (regardless of an infertility diagnosis, marital status, or sexual orientation) in June 2016, but the shortage of donors and the existence of long waiting lists for donated gametes in the public healthcare system have been consistently reported [31]. As recipients were expected to be more frequently married or living with a partner and to attend medical appointments with a spouse or partner, a ratio of approximately one donor to two recipients was expected and observed in our sample. The consecutive recruitment of donors and recipients took place in the only Portuguese Public Bank of Gametes, accounting for the generalization of the views of those using the public healthcare system and contributing to overcome selection bias. Nevertheless, a multicentric study based on distinct recruitment strategies, settings (e.g., private centers, outside healthcare settings), and sociocultural contexts [34] is needed to explore the relation between the willingness to donate and participate in distinct research designs and procedures [40, 64]; the attitudes towards research and towards publicly and/or privately funded scientific and medical organizations, medical doctors, and nonprofit or for-profit researchers [21, 65]; and the features and practices demonstrating, fostering, or decreasing trustworthiness.

Conclusion

This study sheds light on the seldom-explored willingness of donors and recipients to donate gametes and embryos for scientific purposes and on the underlying role of attitudes towards research, gender, and relationship with gamete donation. Our empirical findings on beliefs and concerns towards research and researchers of gamete donors and recipients enrich the discussion on the importance of trust and trustworthiness for participation in research [33–35] and might promote inclusivity and diversity [32]. Simultaneously, it helps design and implement responsive science communication strategies, scientific practices, and codes of conduct, which in turn might also foster trust and willingness to donate gametes and embryos. Within a rapidly evolving scientific and technological landscape that has resulted in contentious achievements and increasing demand for donated oocytes, sperm, and embryos [3–5], our results call for the timely assessment of the views of male and female donors and recipients and for their upstream engagement in inclusive and equitable deliberative processes about ethical, legal, regulatory, and social issues associated with research using donated gametes and embryos and its clinical application [3, 7–10]. These findings might help boost a trustworthy, anticipatory, democratic, and people-centered approach to policies, regulations, and practices [8, 66, 67], which also upholds justice, fairness, and equal respect [68–70]. It will hopefully be relevant to build long-term trusting and sustainable relationships between researchers and reproductive and third-party donors [35] and to develop sustainable human gamete and embryo research.

Supplementary Information

Below is the link to the electronic supplementary material.

Author contribution

SS and SPS designed the study. SPS collaborated in data collection. SPS and MS analyzed data. SPS drafted the manuscript. CdF, MS, and SS critically reviewed the manuscript and approved its final version.

Funding

This study was supported by national funding from the FCT — Foundation for Science and Technology (Portuguese Ministry of Science, Technology, and Higher Education), the Operational Programmes Competitiveness and Internationalization (COMPETE 2020) and Human Capital (POPH), Portugal 2020, and the European Union, through the European Regional Development Fund and the European Social Fund, under the project ENGAgED — Bionetworking and citizenship in gamete donation (POCI-01–0145-FEDER-016762; Ref. FCT PTDC/IVC-ESCT/6294/2014), the Unidade de Investigação em Epidemiologia — Instituto de Saúde Pública da Universidade do Porto (EPIUnit) (POCI-01–0145-FEDER-006862; Ref. FCT UIDB/04750/2020), the PhD grant SFRH/BD/122603/2016 (Pinto da Silva S), the contract Ref. DL57/2016/CP1336/CT0001 (de Freitas C), and the FCT investigator contract IF/01674/2015 (Silva S).

Data availability

Data are available from the corresponding author on reasonable request.

Code availability

Not applicable.

Declarations

Ethics approval

Ethical approval was obtained from the Ethics Committee for Health of the Centro Hospitalar Universitário do Porto and the Portuguese Data Protection Authority. This study was conducted in accordance with the ethical standards mentioned in the 1964 Declaration of Helsinki and its later amendments.

Consent to participate

Informed consent was obtained from all participants included in this study.

Consent for publication

Not applicable.

Conflict of interest

The authors declare no competing interests.