Factors associated with the disposition of frozen embryos after a live birth through IVF treatment in China

Navigating the practical challenges and ethical dilemmas of surplus cryopreserved human embryos

Cryopreservation, the use of very low temperatures to preserve structurally intact living cells and tissues, has seen exponential growth in the field of in vitro fertilization (IVF). In the last decade, cryopreservation of embryos and freeze-all protocols have become an essential aspect and a prerequisite for a successful IVF outcome. Moreover, vitrification, which is a fast and safe cryopreservation method, has proved to be an effective choice for cryopreserving gametes and embryos. The increasing number of cryopreserved embryos worldwide in cryobanks and IVF clinics is an undisputable fact that raises important physiological, ethical, and moral considerations that merit careful examination and discussion. Many couples utilizing assisted reproduction will have a surplus of cryopreserved embryos, in other words they already have completed their family without exhausting all the embryos that were created and cryopreserved during the process. Additionally, the global IVF market has also experienced significant growth due to various factors, including advancements in technology, increased awareness about infertility treatments, and changing societal norms towards delayed parenthood. Thus, for the foreseeable future the number of cryopreserved embryos, and the phenomenon of surplus embryos will likely remain unresolved. In the present review, following a description of the cryopreservation method and the physiological changes during the cryopreservation of embryos, the bioethical issues raised by the surplus cryopreserved embryos will be discussed alongside possible solutions for resolving this phenomenon.

Elective egg freezers' disposition decisions: a qualitative study

OBJECTIVE

To explore the factors that influence elective egg freezers' disposition decisions toward their surplus-frozen oocytes.

DESIGN

Qualitative.

SETTING

Not applicable.

PATIENT(S)

Thirty-one participants: 7 past; 6 current; and 18 future oocyte disposition decision-makers.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Qualitative thematic analysis of interview transcripts.

RESULTS

Six inter-related themes were identified related to the decision-making process which are as follows: decisions are dynamic; triggers for the final decision; achieving motherhood; conceptualization of oocytes; the impacts of egg donation on others; and external factors affecting the final disposition outcome. All women reported a type of trigger event for making a final decision (e.g., completing their family). Women who achieved motherhood were more open to donating their oocytes to others but were concerned about the implications for their child and felt responsibility for potential donor children. Women who did not achieve motherhood were unlikely to donate to others due to the grief of not becoming a mother, often feeling alone, misunderstood, and unsupported. Reclaiming oocytes (e.g., taking them home) and closure ceremonies helped some women process their grief. Donating to research was viewed as an altruistic option as oocytes would not be wasted and did not have the "complication" of a genetically-linked child. There was a general lack of knowledge around disposition options at all stages of the process.

CONCLUSION(S)

Oocyte disposition decisions are dynamic and complex for women, exacerbated by a general lack of understanding of these options. The final decision is framed by: whether women achieved motherhood, dealing with grief if they did not achieve motherhood, and considering the complexities of donating to others. Additional decision support through counseling, decision aids, and early consideration of disposition when eggs are initially stored may help women make informed decisions.

Disposition intentions of elective egg freezers toward their surplus frozen oocytes: a systematic review and meta-analysis

OBJECTIVE

To examine the disposition outcomes and disposition intentions of elective egg freezers (EEFs) toward their surplus frozen oocytes and the psychosocial determinants underlying these.

DESIGN

A systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Actual EEFs (women with oocytes in storage), potential EEFs (women investigating elective oocyte cryopreservation or about to freeze their oocytes), and women of reproductive age (women in the community aged ≥18 years).

INTERVENTION(S)

A systematic review was undertaken and electronically searched MEDLINE, Embase, and PsycINFO on the Ovid platform for conference abstracts and peer-reviewed articles, published in English after January 1, 2010. A search strategy combined synonyms for oocyte, cryopreservation, donation, disposition, elective, and attitude. Eligible studies assessed disposition outcomes (how an oocyte was disposed of) and disposition intentions (how women intend to dispose of an oocyte) and/or the psychosocial determinants underlying disposition outcomes and intentions. The Joanna Briggs Institute Prevalence Tool was used to assess the risk of bias. A meta-analysis using random effects was applied to pool proportions of women with similar disposition intentions toward their oocytes.

MAIN OUTCOME MEASURE(S)

Disposition outcomes and intentions toward surplus frozen oocytes: donate to research; donate to others; discard; unsure. Psychosocial determinants (beliefs, attitudes, barriers, and facilitators) of disposition outcomes and intentions.

RESULT(S)

A total of 3,560 records were identified, of which 22 (17 studies) met the inclusion criteria (8 studies from Europe, 7 from North America, and 2 from Asia). No studies reported on past oocyte disposition outcomes. Seventeen studies reported on the future disposition intentions of 5,446 women. Only 2 of the 17 studies reported on the psychosocial determinants of oocyte disposition intentions. There was substantial heterogeneity in the pooled results, which was likely a result of the significant variation in methodology. Actual EEFs were included in eight studies (n = 873), of whom 53% (95% confidence interval [CI], 44-63; I², 87%) would donate surplus oocytes to research, 31% (95% CI, 23-40; I², 72%) were unsure, 26% (95% CI, 17-38; I², 92%) would donate to others, and 12% (95% CI, 6-21; I², 88%) would discard their eggs. Psychosocial determinants: One study reported that 50% of these women were aware of friends and/or family having difficulty conceiving, which may have contributed to their willingness to donate to others. Potential EEFs were included in 4 studies (n = 645), of whom 38% (95% CI, 28-50; I², 84%) would donate to research, 32% (95% CI, 17-51; I², 91%) would donate to others, 29% (95% CI, 17-44; I², 89%) would discard, and 7% (95% CI, 1-27; I², 77%) were unsure. Psychosocial determinants: No studies. Women of reproductive age were included in 5 studies (n = 3,933), of whom 59% (95% CI, 48-70; I², 97%) would donate to research and 46% (95% CI, 35-57; I², 98%) would donate to others. "Unsure" and "discard" were not provided as response options. Psychosocial determinants: One study reported that the facilitators for donation to others included a family member or friend in need, to help others create a family, financial gain, to further science, and control or input over the selection of recipients. Barriers for donation included fear of having a biological child they do not know or who is raised by someone they know.

CONCLUSION(S)

No studies reported on the disposition outcomes of past EEFs. Disposition intentions varied across the three groups; however, "donating to research" was the most common disposition preference. Notably, the second disposition preference for one-third of actual EEFs was "unsure" and for one-third of potential EEFs was "donate to others." There were limited studies for actual and potential EEFs, and only two studies that explored the psychosocial determinants of oocyte disposition intentions. Additionally, these data suggest that disposition decisions change as women progress on their egg freezing journey, highlighting the importance of ongoing contact with the fertility team as intentions may change over time. More research is needed to understand the psychosocial determinants of oocyte disposition decisions so fertility clinics can provide EEFs with the support and information they need to make informed decisions about their stored eggs and reduce the level of uncertainty reported among EEFs and the potential risk of psychological distress and regret.

CLINICAL TRIAL REGISTRATION NUMBER

PROSPERO 2020: CRD42020202733.

Evaluation of the effect of the elective blastocyst-stage embryo transfer and freezing strategy on the abandonment of frozen embryos under the Taiwan National Assisted Reproduction Act

Purpose

To evaluate the relationship between elective blastocyst transfer, freezing strategy, and the abandonment of frozen embryos with a storage time limit of 10 years as specified in the National Assisted Reproduction Act of Taiwan.

Methods

This two-phase retrospective cohort study was conducted at a single tertiary center, Kaohsiung Chang Gung Memorial Hospital (KCGMH), in 2019. Participants were selected from a data registry containing 4167 fresh IVF cycles, including phase 1 cycles from 1999 to 2009 and phase 2 cycles from 2010 to 2014, at KCGMH.

Results

In phase 1, embryo abandonment was associated with the production of more mature oocytes and embryos, the freezing of more embryos, young female age, blastocyst transfer, and positive pregnancy results. After adjustment for confounding factors, only positive pregnancy results (adjusted odds ratio [aOR] 4.38, 95% confidence interval [CI] 3.17, 6.04), the freezing of ≥ 2 embryos (aOR 3.68, 95% CI 3.10, 4.38), the production of ≥ 6 embryos (aOR 1.68, 95% CI 1.03, 2.73), and the use blastocyst transfer (aOR 2.46, 95% CI 1.64, 3.69) remained significantly associated with embryo abandonment. The factors associated with embryo abandonment or possible abandonment were similar in phase 2.

Conclusion

For elective blastocyst stage transfer and a freezing strategy performed according to the Taiwan National Assisted Reproduction Act, a young female age ≤ 35 with positive pregnancy status due to the original IVF treatment, the production of ≥ 6 embryos, and the cryopreservation of ≥ 2 blastocysts may increase the likelihood of abandoning embryos in the future.