Abstract
Purpose
The aim of this study is to determine if donor gamete use is associated with patients’ decisions regarding disposition of supernumerary embryos.
Methods
Patients who intended to undergo an IVF cycle at a single academic center signed an embryo disposition consent form to indicate their disposition preferences for any supernumerary embryos. A retrospective chart review was performed to obtain the embryo disposition declarations and demographic information. The primary outcome was the distribution of embryo disposition choices between patients who used donor gametes compared to patients who did not use donor gametes. Fisher’s exact test was used to compare groups. Logistic regression models were created to determine the association between donor gamete use and disposition decision after adjusting for patient age, body mass index, and nulliparity.
Results
Five hundred six patients were included. Ninety-one (18.0%) patients used donor gametes [46 (9.0%) donor oocytes, 52 (10.3%) donor sperm]. Patients using donor gametes differed from those not using donor gametes when making decisions concerning death of the patient (P < 0.01), simultaneous death (P = 0.04), separation (P < 0.01), discontinuation of ART (P = 0.01), and time-limited storage (P < 0.01). Most patients, regardless of donor or autologous gamete use, awarded embryos to themselves or their partner if given the option. For patients who did not choose this option, excess embryos were generally awarded to research or discarded rather than donating to another couple. Patients using donor gametes were more likely to award embryos to research over discarding.
Conclusion
Patients using donor gametes made different choices regarding supernumerary embryo disposition compared to patients not using donor gametes.
Supplementary Information
The online version contains supplementary material available at 10.1007/s10815-022-02690-y.
Keywords: Embryo disposition, Donor gametes, Supernumerary embryos
Introduction
Over the past four decades, embryo cryopreservation has become an essential component of the in vitro fertilization (IVF) process. Embryo cryopreservation allows couples to store embryos produced from IVF and retain the opportunity for future pregnancies without having to undergo another ovarian stimulation cycle. More recently, advancements in laboratory and vitrification techniques have led to even greater accumulation of supernumerary embryos in both clinic-sponsored and commercial storage facilities [1, 2]. With these practice changes, patients and couples in possession of extra embryos are faced with an ongoing decision regarding the fate of these embryos.
As such, ASRM recommends that patients who cryopreserve embryos have a written form documenting their wishes concerning future embryo disposition [3]. Standard embryo disposition options include discarding the embryos, awarding them to research studies, donating them to another patient or couple, and giving them to a partner. The proportions of patients and couples selecting these options vary significantly with anywhere from 12 to 60% stating they would donate embryos to research while 15–29% would donate to another infertile couple [1, 4–7].
Several studies have investigated factors influencing embryo disposition decisions. White patients were more likely to donate to research than Asian patients [8]. Patients who did not have a religious preference were also more likely to donate to research [9]. On the other hand, patients who were young and expressed concern about the well-being of an embryo (e.g., concern about embryo damage while in storage, embryo usage without the patient’s knowledge, birth defects in a pregnancy from the frozen embryo, etc.) through survey data were more likely to discard embryos [6, 9]. No associations were observed between embryo disposition choices and patient age, parity, and total time in storage [6, 8, 10]. One factor in supernumerary embryo disposition decision-making that has not been evaluated thoroughly is gamete source. The objective of this study was to evaluate the differences in intended embryo disposition decisions of patients using donor gametes. We hypothesized that patients who use donor gametes would be more likely to award supernumerary embryos to research compared to patients who do not use donor gametes.
Materials and methods
This retrospective study was determined exempt by the Duke Institutional Review Board. All patients who initiated an ART cycle at the Duke Fertility Center between September 16, 2015 and December 30, 2019 were identified using the clinic’s Society for Assisted Reproductive Technology Clinic Outcomes Reporting System (SART CORS) database. September 16, 2015 was chosen as the starting date to coincide with the revision of the embryo disposition consent form. All patients who intended to undergo an IVF cycle at the Duke Fertility Center signed this form to indicate their disposition preferences for any supernumerary embryos in specific circumstances. A retrospective chart review of the electronic medical record was then performed to obtain embryo disposition declarations and any missing demographic data. Patients were excluded if an embryo disposition consent form data was not available. Patients who were undergoing oocyte cryopreservation without the intention of creating embryos were also excluded. Each couple was only included once, even if they underwent multiple IVF cycles during the study interval. The data were collected and stored through Duke Research Electronic Data Capture (Vanderbilt University, Nashville, TN) [11, 12].
The declaration of intent for disposition of embryos (Supplementary File 1) is a form adapted from the SART consent form for Cryopreservation, Storage, and Disposition of Embryos. It is completed by patients prior to the start of the IVF cycle. This form addresses the following specific circumstances: (1) death of the patient, (2) death of the spouse or partner, (3) simultaneous death of patient and spouse or partner, (4) divorce or dissolution of relationship, (5) mutually agreed upon discontinuation of IVF, (6) time-limited storage of embryos (the clinic will only maintain cryopreserved embryos for a period of 10 years), and (7) age-limited storage of embryos (the clinic will not transfer embryos into any woman to produce a pregnancy after the woman’s 52nd birthday). In each of these scenarios, there were different options that patients could chose for the disposition of cryopreserved embryos. Patients were instructed to identify only one option for desired embryo disposition in each scenario. These disposition options include award to patient, award to partner, award for research, discard embryos, donate to a designated couple or individual for reproductive purposes, transfer embryos to a gestational carrier, transfer to a different storage facility, and disposition per court decree and/or settlement agreement. The clinic did not have the infrastructure for anonymous embryo donation and therefore did not allow for embryo donation to an unnamed couple or general embryo bank. Every option was not applicable to every scenario (e.g., “Award to patient” is not an option for the “death of patient” scenario). In addition, not every scenario was applicable for every patient (e.g., “Death of partner” scenario was not applicable for single females).
The primary outcome for this analysis was the distribution of embryo disposition choices by scenario. Patients who used donor gametes were compared to patients who did not use donor gametes. Responses from single women were not included in the analysis for the death of partner, simultaneous death, and separation scenarios. The distribution of disposition decisions was compared between groups using Fisher’s exact test. Subsequently, logistic regression models were created to determine the independent association between donor gamete use and disposition decision adjusting for patient age, body mass index (BMI), and nulliparity, which were demographic variables identified in bivariate analyses as significantly different between the donor and non-donor groups. BMI was included in the logistic regression models due to its potential as a surrogate marker for other unmeasured demographic confounders that impacts disposition decision. Subgroup analysis was then performed to determine the extent to which single relationship status, use of donor oocytes, and use of donor sperm modified the association between donor gamete use and embryo disposition decisions. All analyses were performed in STATA 17.0 (StataCorp 2021, College Station, TX).
Results
A total of 619 patients initiated an ART cycle between September 16, 2015 and December 30, 2019. After excluding 79 for blank responses and an additional 34 for oocyte cryopreservation cycles, a total of 506 patients were included in the analysis (Table 1). Further, 415 (82.0%) patients created embryos composed of autologous gametes while 91 (18.0%) patients used donor gametes. Of the patients using donor gametes, 46 (9.0%) used donor oocytes and 52 (10.3%) used donor sperm. The mean patient age was 35.6 years and the mean partner age was 37.2 years. Most patients were female-male couples (90.9%) followed by female-female couples (4.7%), single females (4.0%), and male-male couples (0.4%). The average patient BMI was 27.2 kg/m2. Patient and partner self-identified race were white (60.9%, 62.2%), Asian (12.9%, 10.9%), black or African American (12.1%, 9.8%), Hispanic or Latino (5.7%, 4.3%), and other (1.2%, 1.5%), respectively. Patient race did not affect disposition choices for death of patient (P = 0.12) or death of partner (P = 0.11) scenarios. In all the other scenarios, patients who identified as white were less likely to discard and more likely to donate to research.
Table 1.
Demographic characteristics among patients using donor gametes vs. no donor gametes
| Demographic characteristic | No Donor gamete use (N = 415) | Donor gamete use (N = 91) |
Total (N = 506) | P |
|---|---|---|---|---|
| Age, Mean ± SD (Range) | 34.9 ± 4.2 (21, 43) | 38.6 ± 4.6 (28, 47) | 35.6 ± 4.5 (21, 47) | < 0.01 |
| BMI, Mean ± SD | 26.8 ± 6.1 | 28.9 ± 6.6 | 27.2 ± 6.3 | < 0.01 |
| Nulliparous | 344 (76.8%) | 78 (87.6%) | 422 (78.6%) | 0.02 |
| Patient Race | 0.31 | |||
| White | 249 (60.0%) | 59 (64.8%) | 308 (60.9%) | |
| Asian | 60 (14.5%) | 5 (5.5%) | 65 (12.9%) | |
| Black/African American | 47 (11.3%) | 14 (15.4%) | 61 (12.1%) | |
| Hispanic/Latino | 24 (5.8%) | 5 (5.5%) | 29 (5.7%) | |
| Other | 5 (1.2%) | 1 (1.1%) | 6 (1.2%) | |
| Unknown | 30 (7.2%) | 7 (7.7%) | 37 (7.3%) | |
| Sex of patient and partner | < 0.01 | |||
| Female-Male | 415 (100%) | 45 (49.5%) | 460 (90.9%) | |
| Female-Female | 0 | 24 (26.4%) | 24 (4.7%) | |
| Male-Male | 0 | 2 (2.2%) | 2 (0.4%) | |
| Single female | 0 | 20 (22.0%) | 20 (4.0%) |
As expected, the patients who used donor gametes were older than those who did not use donor gametes (38.6 ± 4.6 vs. 34.9 ± 4.2 years, P < 0.01). The patients who used donor gametes also had a slightly higher BMI (28.9 ± 6.6 vs. 26.8 ± 6.1, P < 0.01) and were more likely to be nulliparous (87.6% vs. 76.8%, P = 0.02). There were no differences between prior IVF attempts (P = 0.06) and the distribution of race (P = 0.31) between the patients who had autologous gametes compared to patients who used donor gametes.
In regards to embryo disposition decisions, the majority of patients in both the donor gamete and autologous gamete groups opted to award embryos to the patient or partner when given the opportunity—a situation that was applicable when considering patient death, partner death, and discontinuation of ART (Table 2). When couples did not opt to award their excess embryos to the patient or partner, the majority awarded the embryos to research or discarded them rather than donating to another couple.
Table 2.
Disposition preferences among patients using donor gametes vs. no donor gametes
| Scenario | Donor gamete use | Disposition Preference | P* | P** | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Award to patient or partner | Research | Discard | Donate | Transfer to carrier | Transfer to storage | Court | Multiple | ||||
|
Death of patient N = 506 |
No N = 415 |
326 (78.6%) | 27 (6.5%) | 39 (9.4%) | 8 (1.9%) | – | – | – | 15 (3.6%) | < 0.01 | < 0.01 |
|
Yes N = 91 |
59 (64.8%) | 18 (19.8%) | 8 (8.8%) | 5 (5.5%) | – | – | – | 1 (1.1%) | |||
|
Death of partner N = 483 |
No N = 412 |
361 (87.6%) | 13 (3.2%) | 23 (5.6%) | 3 (0.7%) | – | – | – | 12 (2.9%) | 0.83 | 0.41 |
|
Yes N = 71 |
65 (91.6%) | 3 (4.2%) | 2 (2.8%) | 0 (0%) | – | – | – | 1 (1.4%) | |||
|
Simultaneous death N = 482 |
No N = 412 |
– | 216 (52.4%) | 139 (33.7%) | 54 (13.1%) | – | – | – | 3 (0.7%) | 0.05 | 0.04 |
|
Yes N = 70 |
– | 46 (65.7%) | 13 (18.6%) | 10 (14.3%) | – | – | – | 1 (1.4%) | |||
|
Separation N = 482 |
No N = 411 |
– | 102 (24.8%) | 100 (24.3%) | – | – | – | 209 (50.8%) | – | < 0.01 | < 0.01 |
|
Yes N = 71 |
– | 13 (18.3%) | 7 (9.9%) | – | – | – | 51 (71.8%) | – | |||
|
Discontinue ART N = 415 |
No N = 342 |
258 (75.4%) | 36 (10.5%) | 41 (12.0%) | 2 (0.6%) | – | – | – | 5 (1.5%) | 0.11 | 0.01 |
|
Yes N = 73 |
51 (69.9%) | 16 (21.9%) | 6 (8.2%) | 0 (0%) | – | – | – | 0 (0%) | |||
|
Time-limited storage N = 496 |
No N = 407 |
– | 155 (38.1%) | 102 (25.1%) | – | – | 150 (36.9%) | – | – | < 0.01 | < 0.01 |
|
Yes N = 89 |
– | 53 (59.6%) | 13 (14.6%) | – | – | 23 (25.8%) | – | – | |||
|
Age-limited storage N = 497 |
No N = 408 |
– | 181 (44.4%) | 116 (28.4%) | 19 (4.7%) | 28 (6.9%) | 61 (15.0%) | – | 3 (0.7%) | 0.02 | 0.09 |
|
Yes N = 89 |
– | 51 (57.3%) | 12 (13.5%) | 5 (5.6%) | 10 (11.2%) | 10 (11.2%) | – | 1 (1.1%) | |||
*Fisher’s exact test
**Logistic regression model adjusting for patient age, BMI, and nulliparity
After adjusting for age, BMI, and nulliparity, patients using donor gametes differed from those not using donor gametes when making decisions concerning death of the patient (P < 0.01), simultaneous death (P = 0.04), separation (P < 0.01), discontinue ART (P = 0.01), and time-limited storage (P < 0.01) scenarios. No significant differences were observed for the death of partner (P = 0.41) and age-limited storage (P = 0.09) scenarios.
When considering death of the patient and discontinuation of ART, the majority of patients with embryos composed of donor gametes as well as patients with embryos composed of autologous gametes both preferred to award the embryo to the patient or partner (death of patient: 64.8%, 78.6%, discontinuation of ART: 69.9%, 75.4%). However, when couples did not opt to award their excess embryos to the patient or partner, patients with embryos containing donor gametes preferred awarding the embryos to research over discarding and donating (death of patient: 19.8% for research, 8.8% for discard, 5.5% for donate, P < 0.01, discontinuation of ART: 21.9% for research, 8.2% for discard, 0% for donate, P = 0.07). In contrast, patients with embryos from autologous gametes preferred discarding embryos over research and donating (death of patient: 9.4% for discard, 6.5% for research, 1.9% for donate, P < 0.01, discontinuation of ART: 12.0% for discard, 10.5% for research, 0.6% for donate, P = 0.07). When considering separation (i.e., divorce or dissolution of the relationship), patients preferred to determine custody of the embryo through court decree or settlement agreement; patients using donor gametes preferred this option to a larger degree (71.8% for those using donor gametes, 50.8% for those not using donor gametes, P < 0.01). When considering simultaneous death and time-limited storage, more patients in both the donor gamete and autologous gamete groups selected the research option compared to any other option. However, those with embryos composed of donor gametes selected the research option to a greater extent than those with embryos composed of autologous gametes, and those with embryos composed of autologous gametes selected the discard option to a greater extent than those with embryos composed of donor gametes.
Subgroup analyses were then performed to evaluate whether embryo disposition decisions differed by single status (Table 3) and donor oocyte or donor sperm recipient statuses (Table 4). The relationship between donor gamete use and disposition decision by single status was assessed only among the time-limited and age-limited storage scenarios as the other scenarios were not uniformly applicable to both single and not-single patients. In these two scenarios, single women using donor gametes were more likely to discard supernumerary embryos rather than transfer to storage or donating to a designated individual, though these findings were not statistically significant (time-limited storage: P = 0.23, age-limited storage: P = 0.27). Nonetheless, since the combined group of patients using donor gametes showed a different trend toward discarding less and donating to research more, single status does not appear to explain the observed disposition preferences in the couples using donor gametes.
Table 3.
Disposition preferences among patients using donor gametes by single relationship status
| Scenario | Single status | Disposition preference | P* | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Award to patient or partner | Research | Discard | Donate | Transfer to carrier | Transfer to storage | Court | Multiple | |||
|
Time-limited storage N = 89 |
No N = 70 |
– | 42 (60.0%) | 8 (11.4%) | – | – | 20 (28.6%) | – | – | 0.23 |
|
Yes N = 19 |
– | 11 (57.9%) | 5 (26.3%) | – | – | 3 (15.8%) | – | – | ||
|
Age-limited storage N = 89 |
No N = 70 |
– | 39 (55.7%) | 8 (11.4%) | 3 (4.3%) | 10 (14.3%) | 9 (12.9%) | – | 1 (1.4%) | 0.27 |
|
Yes N = 19 |
– | 12 (63.2%) | 4 (21.1%) | 2 (10.5%) | 0 (0%) | 1 (5.3%) | – | 0 (0%) | ||
*Fisher’s exact test
Table 4.
Disposition preferences among patients using donor oocyte or donor sperm vs. no donor gametes
| Scenario | Gamete Source | Disposition Preference | P* | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Award to patient or partner | Research | Discard | Donate | Transfer to carrier | Transfer to storage | Court | Multiple | |||
|
Death of patient N = 499** |
Autologous N = 415 |
326 (78.6%) | 27 (6.5%) | 39 (9.4%) | 8 (1.9%) | – | – | – | 15 (3.6%) | – |
|
Donor oocyte N = 39 |
29 (74.4%) | 6 (15.4%) | 3 (7.7%) | 0 (0%) | – | – | – | 1 (2.6%) | 0.38 | |
|
Donor sperm N = 45 |
26 (57.8%) | 11 (24.4%) | 5 (11.1%) | 3 (6.7%) | – | – | – | 0 (0.0%) | < 0.01 | |
|
Death of partner N = 479 |
Autologous N = 412 |
361 (87.6%) | 13 (3.2%) | 23 (5.6%) | 3 (0.7%) | – | – | – | 12 (2.9%) | – |
|
Donor oocyte N = 39 |
33 (84.6%) | 3 (7.7%) | 2 (5.1%) | 0 (0%) | – | – | – | 1 (2.6%) | 0.58 | |
|
Donor sperm N = 28 |
28 (100.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | – | – | – | 0 (0.0%) | 0.64 | |
|
Simultaneous death N = 478 |
Autologous N = 412 |
– | 216 (52.4%) | 139 (33.7%) | 54 (13.1%) | – | – | – | 3 (0.7%) | – |
|
Donor oocyte N = 38 |
– | 23 (60.5%) | 8 (21.1%) | 6 (15.8%) | – | – | – | 1 (2.6%) | 0.20 | |
|
Donor sperm N = 28 |
– | 21 (75.0%) | 4 (14.3%) | 3 (10.7%) | – | – | – | 0 (0.0%) | 0.10 | |
|
Separation N = 478 |
Autologous N = 411 |
– | 102 (24.8%) | 100 (24.3%) | - | – | – | 209 (50.9%) | – | – |
|
Donor oocyte N = 39 |
– | 8 (20.5%) | 5 (12.8%) | - | – | – | 26 (66.7%) | – | 0.14 | |
|
Donor sperm N = 28 |
– | 4 (14.3%) | 1 (3.6%) | - | – | – | 23 (82.1%) | – | < 0.01 | |
|
Discontinue ART N = 412 |
Autologous N = 342 |
258 (75.4%) | 36 (10.5%) | 41 (12.0%) | 2 (0.6%) | – | – | – | 5 (1.5%) | – |
|
Donor oocyte N = 35 |
25 (71.4%) | 6 (17.1%) | 4 (11.4%) | 0 (0%) | – | – | – | 0 (0%) | 0.72 | |
|
Donor sperm N = 35 |
24 (68.6%) | 9 (25.7%) | 2 (5.7%) | 0 (0.0%) | – | - | – | 0 (0.0%) | 0.13 | |
|
Time-limited storage N = 489 |
Autologous N = 407 |
– | 155 (38.1%) | 102 (25.1%) | – | – | 150 (36.9%) | – | – | – |
|
Donor oocyte N = 38 |
– | 19 (50.0%) | 6 (15.8%) | – | – | 13 (34.2%) | – | – | 0.29 | |
|
Donor sperm N = 44 |
– | 29 (66.0%) | 5 (11.4%) | – | – | 10 (22.7%) | – | – | < 0.01 | |
|
Age-limited storage N = 491 |
Autologous N = 408 |
– | 181 (44.4%) | 116 (28.4%) | 19 (4.7%) | 28 (6.9%) | 61 (15.0%) | – | 3 (0.7%) | – |
|
Donor oocyte N = 38 |
– | 18 (47.4%) | 6 (15.8%) | 1 (2.6%) | 7 (18.4%) | 6 (15.8%) | – | 0 (0%) | 0.16 | |
|
Donor sperm N = 45 |
– | 29 (64.4%) | 5 (11.1%) | 3 (6.7%) | 3 (6.7%) | 4 (8.9%) | – | 1 (2.2%) | 0.03 | |
*Fisher’s exact test with comparison of donor to autologous gamete use
**Excludes couples that used both donor sperm and donor oocyte (N = 6)
When considering donor oocyte and donor sperm recipient status, the distribution of disposition preferences displays similar trends as when the donor recipient population is viewed as a collective. However, these differences are more pronounced in those using donor sperm than those using donor oocytes. For example, as previously discussed in the death of patient scenario, patients using any donor gamete material were more likely to prefer donating to research compared to those not using donor gametes (19.8% vs. 6.5%). The preference for research was more evident in patients using donor sperm only (24.4%) compared to patients using donor oocyte only (15.4%). Similar findings were observed in the simultaneous death, discontinue ART, time-limited storage, and age-limited storage scenarios. Regarding the separation scenario, patients using only donor oocyte or only donor sperm were also more likely to determine custody of the embryo through court decree or settlement agreement, but those using only donor sperm did so to a larger extent (50.9% for autologous gametes vs. 66.7% for donor oocytes only [P = 0.14] and 82.1% for donor sperm only [P < 0.01]).
Discussion
This study characterized patients’ initial embryo disposition decisions. In general, most patients opted to award embryos to the patient or partner when given the opportunity, regardless of donor or autologous gamete use. When patients did not choose this option, they were more likely to award excess embryos to research or discard rather than donating to another couple. Only a few patients decided to donate surplus embryos to a designated couple. After controlling for age, BMI, and nulliparity, significant differences between selected disposition decisions among couples using donor gametes compared to those not using donor gametes were observed in all the scenarios except the death of partner and age-limited storage scenarios. Specifically, patients who used donor gametes were more likely to award excess embryos to research. Subgroup analyses showed that single relationship status did not drive these findings. Couples using donor sperm were more likely to award supernumerary embryos to research than those using donor oocytes. This finding suggests possible gender differences with regard to future disposition of genetically related or non-genetically related offspring.
Only one prior study (Hill and Freeman 2011) has evaluated embryo disposition decisions based on the source of the gametes, comparing autologous and use of donor oocytes [13]. This study at a single IVF center in the USA evaluated the final disposition decision of 1262 couples who used autologous oocytes versus 272 couples who used donor oocytes. Among couples using donor oocytes, 56% donated to another couple, 6% awarded to research, and 38% discarded. Among couples not using donor oocytes, 21% donated to another couple, 11% awarded to research, and 68% discarded. Our findings are considerably different from those of Hill and Freeman. While our study similarly showed greater proportions of patients with autologous embryos preferring to discard, Hill and Freeman observed a large proportion of couples deciding to donate supernumerary embryos to another couple. In most of our scenarios, very few patients (0.0–14.3%) opted to donate to another couple. One possible explanation for this finding is our clinic’s requirement to designate a specific couple or individual for donation. Anonymous embryo donation was not an option at our clinic for embryo disposition. Instead, couples using donor oocytes were more likely to donate their embryos to research. Overall, these findings suggest that couples using donor gametes are more likely to “donate” their embryos, whether this is to research or to another couple. Additionally, longitudinal cultural, political, and societal changes may have influenced our patients’ decisions compared to the patients in Hill and Freeman’s study between 1998 and 2008. Lastly, Hill and Freeman evaluated final actual disposition decisions whereas we focused on initial disposition decisions. Additional studies are needed to evaluate whether significant changes occur between initial and final embryo disposition decisions.
Although this study does not directly investigate factors contributing to a couple’s disposition decisions, one hypothesis for the differing disposition decisions among couples with donor and non-donor embryo compositions relates to conceptualizations of their embryos. Provoost et al. [14] conducted interviews of infertility patients to describe the narratives used by patients to talk about their embryos. One of the themes that emerged was the value placed on an embryo based on genetic linkage. Couples who brought up themes of a genetic link during their narrative were less likely to want to donate excess embryos to another couple. The other component that played a role in patients’ decision making was confidence in medical science, which was linked to decisions to award surplus embryos to research. While the Provoost study did not include couples that used donor gametes, the values placed on genetic linkage may potentially influence varying conceptualizations of an embryo between patients using autologous versus donor gametes.
Another factor that appeared to contribute to a couple’s disposition decisions was the specific scenario under consideration. Significant disparities were found in the disposition decisions of couples using donor gametes compared to autologous gametes when considering death of the patient that were not observed when considering death of the partner. Somewhat intuitively, in death of the partner scenarios, the overwhelming majority opted to award the embryo to the still living patient, regardless of gamete status. Usability of the embryos might play a role. As our cohort was predominantly composed of female-male couples, in the scenario when the male partner dies, the female patient can still undergo implantation of the embryo in the future. By contrast, when the patient dies, the male partner is not able to directly use the embryo without assistance of a gestational carrier or other female partner. Female-female couples, all of which are in the cohort using donor gametes, may also have different disposition preferences compared female-male couples. Future qualitative studies investigating the reasons underlying disposition choices in different populations would elucidate a better understanding of patient decision making processes.
One of the strengths of the study is the evaluation of disposition decisions in accordance with the initial consent form documented by patients. This time point in the process of embryo disposition is particularly important as it is often the first time a couple has deliberated on this complicated and uniquely personal matter. As time passes, the clinic often relies on this documentation when patients prolong deferral of final embryo disposition decisions and are subsequently lost to follow-up. In addition, the submitted declaration includes several hypothetical situations for the patients to take into consideration. Our findings showed similar trends in all the scenarios and statistically significant differences between patients using donor material compared to those not using donor material in all scenarios except death of partner and age-limited storage scenarios.
Nonetheless, it is important to understand decisions surrounding embryo disposition as a dynamic process that unfolds as couples start, undergo, and complete the IVF process. During the early stages when patients are initially confronted with embryo disposition decisions, they are often more focused on having a child and are not fully prepared to make decisions about their future hypothetical embryos [15]. As they go through the IVF process, the idea of having surplus embryos may become less abstract. At our clinic, all patients undergoing IVF are required to fill out an initial embryo disposition form prior to starting ovarian stimulation, and they are subsequently asked to confirm their decision prior to final embryo disposition. It is important to address any alterations in embryo disposition decisions as patients’ reproductive goals change [16]. IVF clinics should consider counseling patients with easily comprehensible informational materials about disposition options both prior to embryo cryopreservation as well as checking in at regular intervals to assess patients’ evolving preferences. Further studies are needed to better characterize the optimal materials and intervals to facilitate patient embryo disposition decisions.
One of the limitations of the study is the female-focused approach to fertility care that may result in an unintended bias toward the female voice. While the embryo disposition forms are meant to represent a couple’s joint choice, it is possible that one party plays a larger role in the decision making process. In addition, our data did not contain additional information on the couple’s personal beliefs and religious affiliation, which may be potential confounders. Further studies are also needed to evaluate whether knowledge of cycle information, such as plans for preimplantation genetic testing, influences initial embryo disposition decisions.
Another limitation is incomplete embryo disposition forms. All of the 506 patients included in this study indicated a disposition decision for the death of patient scenario. However, 2–18% of participants omitted decisions in other scenarios, and 0.7–3.6% of participants chose multiple options for certain disposition decisions. A further select few chose to write their own disposition option (e.g., choosing to donate to an unspecified couple when the clinic only allowed for directed donation to a designated person). These blank and inconsistent declarations complicate final embryo disposition determinations by clinics, especially when patients are lost to follow-up. In addition, these conflicting responses may be indicative of a patient’s desire to defer disposition decisions or finding the current options inadequate. It may therefore be important to explore better options for the consenting process for embryo disposition throughout a patient’s reproductive journey in order to avoid accumulation of embryos with unclear disposition. Lastly, IVF clinics should maintain a stable infrastructure that will allow them to carry out the embryo disposition options offered, whether it be discarding, awarding to research, or donating to another couple. In particular, our study exemplifies how patients using donor gametes were more likely to award excess embryos to research—a disposition option that fertility clinics should consider having readily available when final embryo disposition choices are carried out.
Conclusions
Supernumerary embryo disposition decisions are influenced by the unique lived experiences of each patient and their partner. This study provides insight into initial embryo disposition decisions of patients undergoing ART and the differences seen in disposition preferences when donor gametes are used during the creation of embryos. Patients should be educated about their options for embryo disposition throughout the IVF process and beyond. When discussing these choices, physicians must acknowledge the complexity of these decisions, recognize their own biases, and provide counseling with sensitivity and compassion. Finally, it is important to maintain capability to execute final embryo disposition decisions.
Supplementary Information
Below is the link to the electronic supplementary material.
Author contribution
All authors contributed to the study conception and design. The research design was developed by Shelun Tsai, Jenna Hynes, Douglas Raburn, and Anne Stiner. Data collection was performed by Nicole Zanolli. The statistical analysis was performed by Shelun Tsai and Anne Steiner. The first draft of the manuscript was written by Shelun Tsai and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.
Funding
The authors did not receive support from any organization for the submitted work.
Data availability
The datasets generated during the study are available from the corresponding author on reasonable request.
Code availability
Not applicable.
Declarations
Ethics approval
This study was granted exempt status by the Institutional Review Board of Duke University because no identifiable private information was collected.
Consent to participate
This was a retrospective cohort study and additional consents were not applicable. No identifiable private information was collected.
Consent for publication
Not applicable.
Conflict of interest
The authors declare no conflict of interest.
Footnotes
Publisher's note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Data Availability Statement
The datasets generated during the study are available from the corresponding author on reasonable request.
Not applicable.