The status of preimplantation genetic testing in the UK and USA

One size does not fit all: the personal nature of completed embryo donation

PURPOSE

To assess factors associated with embryo donation among individuals interested in donation in the United States.

METHODS

An invitation to complete the 123-item survey was emailed from June to September 2022 to patients at a private practice fertility clinic with interest in donation at the time of IVF. Survey questions included disposition decision, attitudes about embryo status and genetic relatedness, donation disclosure, ideal donation arrangement, and decision satisfaction.

RESULTS

Three hundred thirty-seven completed the survey. Two hundred thirty donated to another person(s), 75 discarded embryos, 25 remained undecided, and disposition was unknown for 7 respondents. There were no demographic differences between groups based on final disposition or use of donor gametes. Few gamete recipients were interested in donation due to biological attachment to embryos. Final embryo disposition was associated with religious factors, not wanting to waste embryos, and storage fee concerns. Final disposition was also significantly associated with concern about donor-conceived children's (DCP) welfare, being denied the ability to complete donation, personal IVF outcomes, financial or legal issues, future contact with DCP, cognitive appraisal of disposition, beliefs about embryos, someone else raising their genetic child, anonymity, and beliefs about DCP not knowing genetic relationships (p < .001). Donation to others was associated with less regret and greater satisfaction with the emotional/medical aspects of donation and counseling compared to those who discarded embryos (p < .001).

CONCLUSION

The decision to donate embryos to another person(s) is complex. Counseling that considers individual circumstances, values, and evolving dynamics may facilitate informed decision-making for those navigating infertility treatment, family building, and embryo disposition.

Enhancing clinical utility: deep learning-based embryo scoring model for non-invasive aneuploidy prediction

BACKGROUND

The best method for selecting embryos ploidy is preimplantation genetic testing for aneuploidies (PGT-A). However, it takes more labour, money, and experience. As such, more approachable, non- invasive techniques were still needed. Analyses driven by artificial intelligence have been presented recently to automate and objectify picture assessments.

METHODS

In present retrospective study, a total of 3448 biopsied blastocysts from 979 Time-lapse (TL)-PGT cycles were retrospectively analyzed. The "intelligent data analysis (iDA) Score" as a deep learning algorithm was used in TL incubators and assigned each blastocyst with a score between 1.0 and 9.9.

RESULTS

Significant differences were observed in iDAScore among blastocysts with different ploidy. Additionally, multivariate logistic regression analysis showed that higher scores were significantly correlated with euploidy (p < 0.001). The Area Under the Curve (AUC) of iDAScore alone for predicting euploidy embryo is 0.612, but rose to 0.688 by adding clinical and embryonic characteristics.

CONCLUSIONS

This study provided additional information to strengthen the clinical applicability of iDAScore. This may provide a non-invasive and inexpensive alternative for patients who have no available blastocyst for biopsy or who are economically disadvantaged. However, the accuracy of embryo ploidy is still dependent on the results of next-generation sequencing technology (NGS) analysis.

Economic evaluations of assisted reproductive technologies in high-income countries: a systematic review

STUDY QUESTION

Which assited reproductive technology (ART) interventions in high-income countries are cost-effective and which are not?

SUMMARY ANSWER

Among all ART interventions assessed in economic evaluations, most high-cost interventions, including preimplantation genetic testing for aneuploidy (PGT-A) for a general population and ICSI for unexplained infertility, are unlikely to be cost-effective owing to minimal or no increase in effectiveness.

WHAT IS KNOWN ALREADY

Approaches to reduce costs in order to increase access have been identified as a research priority for future infertility research. There has been an increasing number of ART interventions implemented in routine clinical practice globally, before robust assessments of evidence on economic evaluations. The extent of clinical effectiveness of some studied comparisons has been evaluated in high-quality research, allowing more informative decision making around cost-effectiveness.

STUDY DESIGN, SIZE, DURATION

We performed a systematic review and searched seven databases (MEDLINE, PUBMED, EMBASE, COCHRANE, ECONLIT, SCOPUS, and CINAHL) for studies examining ART interventions for infertility together with an economic evaluation component (cost-effectiveness, cost-benefit, cost-utility, or cost-minimization assessment), in high-income countries, published since January 2011. The last search was 22 June 2022.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Two independent reviewers assessed publications and included those fulfilling the eligibility criteria. Studies were examined to assess the cost-effectiveness of the studied intervention, as well as the reporting quality of the study. The chosen outcome measure and payer perspective were also noted. Completeness of reporting was assessed against the Consolidated Health Economic Evaluation Reporting Standard. Results are presented and summarized based on the intervention studied.

MAIN RESULTS AND THE ROLE OF CHANCE

The review included 40 studies which were conducted in 11 high-income countries. Most studies (n = 34) included a cost-effectiveness analysis. ART interventions included medication or strategies for controlled ovarian stimulation (n = 15), IVF (n = 9), PGT-A (n = 7), single embryo transfer (n = 5), ICSI (n = 3), and freeze-all embryo transfer (n = 1). Live birth was the mostly commonly reported primary outcome (n = 27), and quality-adjusted life years was reported in three studies. The health funder perspective was used in 85% (n = 34) of studies. None of the included studies measured patient preference for treatment. It remains uncertain whether PGT-A improves pregnancy rates compared to IVF cycles managed without PGT-A, and therefore cost-effectiveness could not be demonstrated for this intervention. Similarly, ICSI in non-male factor infertility appears not to be clinically effective compared to standard fertilization in an IVF cycle and is therefore not cost-effective. Interventions such as use of biosimilars or HMG for ovarian stimulation are cheaper but compromise clinical effectiveness.

LIMITATIONS, REASONS FOR CAUTION

Lack of both preference-based and standardized outcomes limits the comparability of results across studies. The selection of efficacy evidence offered for some interventions for economic evaluations is not always based on high-quality randomized trials and systematic reviews. In addition, there is insufficient knowledge of the willingness to pay thresholds of individuals and state funders for treatment of infertility. There is variable quality of reporting scores, which might increase uncertainty around the cost-effectiveness results.

WIDER IMPLICATIONS OF THE FINDINGS

Investment in strategies to help infertile people who utilize ART is justifiable at both personal and population levels. This systematic review may assist ART funders decide how to best invest to maximize the likelihood of delivery of a healthy child.

STUDY FUNDING/COMPETING INTEREST(S)

There was no funding for this study. E.C. and R.W. receive salary support from the National Health and Medical Research Council (NHMRC) through their fellowship scheme (EC GNT1159536, RW 2021/GNT2009767). M.D.-T. reports consulting fees from King Fahad Medical School. All other authors have no competing interests to declare.

REGISTRATION NUMBER

Prospero CRD42021261537.

Preimplantation genetic testing in couples with balanced chromosome rearrangement: a four-year period real world retrospective cohort study

BACKGROUND

Couples with balanced chromosome rearrangement (BCR) are at high risk of recurrent miscarriages or birth defects due to chromosomally abnormal embryos. This study aimed to provide real-world evidence of the euploidy rate of blastocysts from couples with BCR using preimplantation genetic testing (PGT) and to guide pretesting genetic counselling.

METHODS

A continuous four-year PGT data from couples with BCR were retrospectively analyzed. Biopsied trophectoderm cells were amplified using whole genome amplification, and next-generation sequencing was performed to detect the chromosomal numerical and segmental aberrations. Clinical data and molecular genetic testing results were analyzed and compared among the subgroups.

RESULTS

A total of 1571 PGT cycles with 5942 blastocysts were performed chromosomal numerical and segmental aberrations detection during the four years. Of them, 1034 PGT cycles with 4129 blastocysts for BCR couples were included; 68.96% (713/1034) PGT cycles had transferable euploid embryos. The total euploidy rate of blastocysts in couples carrying the BCR was 35.29% (1457/4129). Couples with complex BCR had euploid blastocyst rates similar to those of couples with non-complex BCR (46.15% vs. 35.18%, P > 0.05). Chromosome inversion had the highest chance of obtaining a euploid blastocyst (57.27%), followed by Robertsonian translocation (RobT) (46.06%), and the lowest in reciprocal translocation (RecT) (30.11%) (P < 0.05). Couples with males carrying RobT had higher rates of euploid embryo both in each PGT cycles and total blastocysts than female RobT carriers did, despite the female age in male RobT is significant older than those with female RobT (P < 0.05). The proportions of non-carrier embryos were 52.78% (95/180) and 47.06% (40/85) in euploid blastocysts from couples with RecT and RobT, respectively (P > 0.05). RecT had the highest proportion of blastocysts with translocated chromosome-associated abnormalities (74.23%, 1527/2057), followed by RobT (54.60%, 273/500) and inversion (30.85%, 29/94) (P < 0.05).

CONCLUSIONS

In couples carrying BCR, the total euploidy rate of blastocysts was 35.29%, with the highest in inversion, followed by RobT and RecT. Even in couples carrying complex BCR, the probability of having a transferable blastocyst was 46.15%. Among the euploid blastocysts, the non-carrier ratios in RecT and RobT were 52.78% and 47.06%, respectively. RecT had the highest proportion of blastocysts with translocated chromosome-associated abnormalities.

Pregnancies through oocyte donation. A mini review of pathways involved in placental dysfunction

Pregnancies resulting from assisted reproductive techniques (ART) are increasingly prevalent worldwide. While most pregnancies conceived through in-vitro fertilization (IVF) progress without complications, mounting evidence suggests that these pregnancies are at a heightened risk of adverse perinatal outcomes. Specifically, IVF pregnancies involving oocyte donation have garnered attention due to numerous reports indicating an elevated risk profile for pregnancy-related complications within this subgroup of patients. The precise mechanisms contributing to this increased risk of complications remain incompletely understood. Nonetheless, it is likely that they are mediated by an abnormal immune response at the fetal-maternal interface. Additionally, these outcomes may be influenced by baseline patient characteristics, such as the etiology of infertility, absence of corpus luteum, and variations in endometrial preparation protocols, among other factors. This review aims to succinctly summarize the most widely accepted mechanisms that potentially contribute to the onset of placental dysfunction in pregnancies conceived through oocyte donation.

A comparison of morphokinetic models and morphological selection for prioritizing euploid embryos: a multicentre cohort study

STUDY QUESTION

Are morphokinetic models better at prioritizing a euploid embryo for transfer over morphological selection by an embryologist?

SUMMARY ANSWER

Morphokinetic algorithms lead to an improved prioritization of euploid embryos when compared to embryologist selection.

WHAT IS KNOWN ALREADY

PREFER (predicting euploidy for embryos in reproductive medicine) is a previously published morphokinetic model associated with live birth and miscarriage. The second model uses live birth as the target outcome (LB model).

STUDY DESIGN, SIZE, DURATION

Data for this cohort study were obtained from 1958 biopsied blastocysts at nine IVF clinics across the UK from January 2021 to December 2022.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The ability of the PREFER and LB models to prioritize a euploid embryo was compared against arbitrary selection and the prediction of four embryologists using the timelapse video, blinded to the morphokinetic time stamp. The comparisons were made using calculated percentages and normalized discounted cumulative gain (NDCG), whereby an NDCG score of 1 would equate to all euploid embryos being ranked first. In arbitrary selection, the ploidy status was randomly assigned within each cycle and the NDGC calculated, and this was then repeated 100 times and the mean obtained.

MAIN RESULTS AND THE ROLE OF CHANCE

Arbitrary embryo selection would rank a euploid embryo first 37% of the time, embryologist selection 39%, and the LB and PREFER ploidy morphokinetic models 46% and 47% of the time, respectively. The AUC for LB and PREFER model was 0.62 and 0.63, respectively. Morphological selection did not significantly improve the performance of both morphokinetic models when used in combination. There was a significant difference between the NDGC metric of the PREFER model versus embryologist selection at 0.96 and 0.87, respectively (t = 14.1, P < 0.001). Similarly, there was a significant difference between the LB model and embryologist selection with an NDGC metric of 0.95 and 0.87, respectively (t = 12.0, P < 0.001). All four embryologists ranked embryos similarly, with an intraclass coefficient of 0.91 (95% CI 0.82-0.95, P < 0.001).

LIMITATIONS, REASONS FOR CAUTION

Aside from the retrospective study design, limitations include allowing the embryologist to watch the time lapse video, potentially providing more information than a truly static morphological assessment. Furthermore, the embryologists at the participating centres were familiar with the significant variables in time lapse, which could bias the results.

WIDER IMPLICATIONS OF THE FINDINGS

The present study shows that the use of morphokinetic models, namely PREFER and LB, translates into improved euploid embryo selection.

STUDY FUNDING/COMPETING INTEREST(S)

This study received no specific grant funding from any funding agency in the public, commercial or not-for-profit sectors. Dr Alison Campbell is minor share holder of Care Fertility. All other authors have no conflicts of interest to declare. Time lapse is a technology for which patients are charged extra at participating centres.

TRIAL REGISTRATION NUMBER

N/A.

Association between a morphokinetic ploidy prediction model risk score and miscarriage and live birth: a multicentre cohort study

OBJECTIVE

To determine whether the aneuploidy risk score from a morphokinetic ploidy prediction model, Predicting Euploidy for Embryos in Reproductive Medicine (PREFER), is associated with miscarriage and live birth outcomes.

DESIGN

Multicentre cohort study.

SETTING

Nine in vitro fertilization clinics in the United Kingdom.

PATIENTS

Data were obtained from the treatment of patients from 2016-2019. A total of 3587 fresh single embryo transfers were included; preimplantation genetic testing for aneuploidy) cycles were excluded.

INTERVENTION

PREFER is a model developed using 8,147 biopsied blastocyst specimens to predict ploidy status using morphokinetic and clinical biodata. A second model using only morphokinetic (MK) predictors was developed, P PREFER-MK. The models will categorize embryos into the following three risk score categories for aneuploidy: "high risk," "medium risk," and "low risk."

MAIN OUTCOME MEASURES

The primary outcomes are miscarriage and live birth. Secondary outcomes include biochemical clinical pregnancy per single embryo transfer.

RESULTS

When applying PREFER, the miscarriage rates were 12%, 14%, and 22% in the "low risk," "moderate risk," and "high risk" categories, respectively. Those embryos deemed "high risk" had a significantly higher egg provider age compared with "low risk," and there was little variation in risk categories in patients of the same age. The trend in miscarriage rate was not seen when using PREFER-MK; however, there was an association with live birth, increasing from 38%-49% and 50% in the "high risk," "moderate risk," and "low risk" groups, respectively. An adjusted logistic regression analysis demonstrated that PREFER-MK was not associated with miscarriage when comparing "high risk" to "moderate risk" embryos (odds ratio [OR], 0.87; 95% confidence interval [CI], 0.63-1.63) or "high risk" to "low risk" embryos (OR, 1.07; 95% CI, 0.79-1.46). An embryo deemed "low risk" by PREFER-MK was significantly more likely to result in a live birth than those embryos graded "high risk" (OR, 1.95; 95% CI, 1.65-2.25).

CONCLUSION

The PREFER model's risk scores were significantly associated with live births and miscarriages. Importantly, this study also found that this model applied too much weight to clinical factors, such that it could no longer rank a patient's embryos effectively. Therefore, a model including only MKs would be preferred; this was similarly associated with live birth but not miscarriage.

Making a good egg: human oocyte health, aging, and in vitro development

Mammalian eggs (oocytes) are formed during fetal life and establish associations with somatic cells to form primordial follicles that create a store of germ cells (the primordial pool). The size of this pool is influenced by key events during the formation of germ cells and by factors that influence the subsequent activation of follicle growth. These regulatory pathways must ensure that the reserve of oocytes within primordial follicles in humans lasts for up to 50 years, yet only approximately 0.1% will ever be ovulated with the rest undergoing degeneration. This review outlines the mechanisms and regulatory pathways that govern the processes of oocyte and follicle formation and later growth, within the ovarian stroma, through to ovulation with particular reference to human oocytes/follicles. In addition, the effects of aging on female reproductive capacity through changes in oocyte number and quality are emphasized, with both the cellular mechanisms and clinical implications discussed. Finally, the details of current developments in culture systems that support all stages of follicle growth to generate mature oocytes in vitro and emerging prospects for making new oocytes from stem cells are outlined.

Establishment of linkage phase, using Oxford Nanopore Technologies, for preimplantation genetic testing of Coffin-Lowry syndrome with a de novo RPS6KA3 mutation

Background: This study aimed to perform preimplantation genetic testing (PGT) for a female Coffin-Lowry Syndrome (CLS) patient with a de novo mutation (DNM) in RPS6KA3. It was challenging to establish the haplotype in this family because of the lack of information from affected family members. Hence, we explored a new and reliable strategy for the detection of the DNM in PGT, using Oxford Nanopore Technologies (ONT) and the MARSALA platform. Methods: We performed whole-exome sequencing (WES) on the proband and confirmed the pathogenic mutation by Sanger sequencing. The proband then underwent PGT to prevent the transmission of the pathogenic mutation to her offspring. We diverged from the conventional methods and used long-read sequencing (LRS) on the ONT platform to directly detect the mutation and nearby SNPs, for construction of the haplotype in the preclinical phase of PGT. In the clinical phase of embryo diagnosis, the MARSALA method was used to detect both the SNP-based haplotype and chromosome copy number variations (CNVs), in each blastocyst. Finally, a normal embryo was selected by comparison to the haplotype of the proband and transferred into the uterus. Sanger sequencing and karyotyping were performed by amniocentesis, at 17 weeks of gestation, to confirm the accuracy of PGT. Results: Using WES, we found the novel, heterozygous, pathogenic c.1496delG (p.Gly499Valfs*25) mutation of RPS6KA3 in the proband. The SNP-based haplotype that was linked to the pathogenic mutation site was successfully established in the proband, without the need for other family members to be tested with ONT. Eight blastocysts were biopsied to perform PGT and were assessed with a haplotype linkage analysis (30 SNP sites selected), to give results that were consistent with direct mutation detection using Sanger sequencing. The results of PGT showed that three of the eight blastocysts were normal, without the DNM. Moreover, the patient had a successful pregnancy, after transfer of a normal blastocyst into the uterus, and delivered a healthy baby. Conclusion: The ONT platform, combined with the MARSALA method, can be used to perform PGT for DNM patients without the need for other samples as a reference.

The nature of embryonic mosaicism across female age spectrum: an analysis of 21,345 preimplantation genetic testing for aneuploidy cycles

Objective

To understand how mosaicism varies across patient-specific variables and clinics.

Design

Cross-sectional cohort.

Setting

Genetic testing laboratory.

Patients

A total of 86,208 embryos from 17,366 patients underwent preimplantation genetic testing for aneuploidy using next-generation sequencing.

Interventions

Mosaic embryos were classified as either low-level (20%-40%) or high-level (40%-80%) and by type of mosaic error: single segmental, complex segmental, single chromosome, or complex abnormal mosaic. The rate of mosaicism was stratified by the Society for Assisted Reproductive Technology age categories: <35 years, 35-37 years, 38-40 years, 41-42 years, and >42 years.

Main Outcome Measures

Distribution of chromosomal findings and prevalence of mosaicism type by age. Probability of creating mosaic embryos in a subsequent cycle.

Results

Among all embryos, 44% were euploid, 40.2% were aneuploid, and 15.8% were mosaic. Both low-level and high-level mosaicism were more prevalent among younger patients. Of all mosaic embryos, the youngest age cohort <35 years had the highest proportions of single and complex segmental mosaicism (37.9% and 6.8%, respectively), whereas those aged >42 years had the highest single whole chromosome and complex abnormal mosaicism (37.1% and 34.0%, respectively). Although there was variability in mosaic rates across clinics, the median mosaic rate over 3 years ranged from 14.48% to 17.72%. A diagnosis of a mosaic embryo in a previous cycle did not increase a patient's odds for having a mosaic embryo in a subsequent cycle.

Conclusions

Mosaicism is overall higher in younger patients, but the complexity of mosaic errors increases with age. A history of mosaicism was not associated with mosaicism in subsequent cycles. Additional research is needed to understand the etiologies of the various subtypes of mosaic embryos and clinical outcomes associated with their transfer.

Preimplantation genetic testing for aneuploidy helps to achieve a live birth with fewer transfer cycles for the blastocyst FET patients with unexplained recurrent implantation failure

PURPOSE

This retrospective cohort study aimed to investigate the value of preimplantation genetic testing for aneuploidy (PGT-A) as a screening test for patients suffering from unexplained recurrent implantation failure (RIF).

METHODS

After screening patients in one reproductive medicine center, twenty-nine, forty-nine and thirty-eight women (< 40 years old) who had suffered unexplained RIF with PGT-A, or RIF without PGT-A, or no RIF with PGT-A were included. The clinical pregnancy rate and live birth rate per transfer, the conservative and optimal cumulative clinical pregnancy rates (CCPR) and live birth rates (CLBR) after three blastocyst FETs were analyzed.

RESULTS

The live birth rate per transfer was significantly higher in the RIF + PGT-A group than that in the RIF + NO PGT-A group (47.6% vs. 24.6%, p = 0.014). After 3 cycles of FET, RIF + PGT-A group had significantly higher conservative CLBR and optimal CLBR compared to the RIF + NO PGT-A group (69.0% vs. 32.7%, p = 0.002 and 73.7% vs. 57.5%, p = 0.016), but had similar conservative and optimal CLBRs compared to the NO RIF + PGT-A group. The number of FET cycles required when half women achieved a live birth was 1 in the PGT-A group and 3 in RIF + NO PGT-A group. The miscarriage rates were not different between the RIF + PGT-A and RIF + NO PGT-A, RIF + PGT-A and NO RIF + PGT-A groups.

CONCLUSION

PGT-A did be superior in reducing the number of transfer cycles required to achieve a similar live birth rate. Further studies to identify the RIF patients who would benefit most from PGT-A are necessary.

Preimplantation genetic testing for aneuploidy is not related to adverse obstetric and neonatal outcomes in singleton pregnancies

STUDY QUESTION

What is the potential impact of preimplantation genetic testing for aneuploidy (PGT-A) on obstetric and neonatal outcomes?

SUMMARY ANSWER

PGT-A is not associated with increased rates of adverse maternal and neonatal outcomes in singleton pregnancies following IVF/ICSI cycles.

WHAT IS KNOWN ALREADY

PGT-A pregnancies may be associated with increased risks of lower birthweight, preterm delivery, and hypertensive disorders compared with natural pregnancies. In a recent meta-analysis, the overall obstetric and neonatal outcomes of PGT-A pregnancies were favorable compared with those of IVF/ICSI pregnancies, although PGT-A pregnancies were associated with a higher risk of hypertensive disorders.

STUDY DESIGN, SIZE, DURATION

A multicenter retrospective cohort study was performed in University-affiliated infertility centers. Single live births following IVF/ICSI between October 2016 and January 2021 were included in the study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 7146 live births after single embryo transfers with (n = 3296) or without (n = 3850) PGT-A were included. The primary outcome was pre-eclampsia and secondary outcomes included gestational diabetes, low birthweight and very low birthweight, cesarean section delivery, emergency cesarean section, as well as preterm birth, birthweight, congenital abnormalities, neonatal sex, Apgar score at 5 min, and neonatal intensive care unit admission. In a subgroup analysis, were included only blastocysts screened with next-generation sequencing (NGS).

MAIN RESULTS AND THE ROLE OF CHANCE

Univariate analysis showed that pre-eclampsia, cesarean section incidence, and low Apgar score were higher in women undergoing PGT-A. However, after performing multivariate logistic and linear regression models accounting for many possible confounders, pregnancies that had been conceived after embryo biopsy showed no increase in adverse obstetric and neonatal outcomes. The subgroup analysis including patients with blastocysts screened by NGS showed a decreased risk of preterm birth in the group undergoing PGT-A.

LIMITATIONS, REASONS FOR CAUTION

Caution should be used when interpreting the data because of its limitations, mainly related to its retrospective design. Although this is a large multicenter study, data acquisition included self-reporting questionnaires, and the deliveries occurred in different institutions with distinct protocols.

WIDER IMPLICATIONS OF THE FINDINGS

The current study does not show any major adverse clinical outcomes after PGT-A. Efforts should be made to promote good quality research on embryo biopsy in terms of neonatal and obstetric outcomes, as well as its long-term consequences.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was obtained for this study. The authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Automation in ART: Paving the Way for the Future of Infertility Treatment

In vitro fertilisation (IVF) is estimated to account for the birth of more than nine million babies worldwide, perhaps making it one of the most intriguing as well as commoditised and industrialised modern medical interventions. Nevertheless, most IVF procedures are currently limited by accessibility, affordability and most importantly multistep, labour-intensive, technically challenging processes undertaken by skilled professionals. Therefore, in order to sustain the exponential demand for IVF on one hand, and streamline existing processes on the other, innovation is essential. This may not only effectively manage clinical time but also reduce cost, thereby increasing accessibility, affordability and efficiency. Recent years have seen a diverse range of technologies, some integrated with artificial intelligence, throughout the IVF pathway, which promise personalisation and, at least, partial automation in the not-so-distant future. This review aims to summarise the rapidly evolving state of these innovations in automation, with or without the integration of artificial intelligence, encompassing the patient treatment pathway, gamete/embryo selection, endometrial evaluation and cryopreservation of gametes/embryos. Additionally, it shall highlight the resulting prospective change in the role of IVF professionals and challenges of implementation of some of these technologies, thereby aiming to motivate continued research in this field.

Does PGT-A affect cumulative live birth rate?

PURPOSE OF REVIEW

Preimplantation genetic testing for the purpose of aneuploidy screening (PGT-A) has increased in use over the last decade.

RECENT FINDINGS

Whether PGT-A benefits all of the patients that choose to employ it has been a concern, as recent studies have highlighted a potential decrease in cumulative live birth rate (CLBR) for younger patients undergoing embryo transfer. However, there are limitations to many of these studies and the intended benefit of PGT-A, which is to aid as a selection tool, thus increasing the live birth rate per transfer, must not be ignored.

SUMMARY

PGT-A was never intended to increase CLBR. The purpose of PGT-A is to maximize the chance at live birth per transfer while minimizing the risk of clinical miscarriage, ongoing aneuploid pregnancy and futile transfers. However, if it harms CLBR in the process that has to be taken into consideration. This review will discuss PGT-A in terms of its benefits, risks, and how it has been shown to affect the cumulative live birth rate within in-vitro fertilization cycles.

Identifying parental and cell-division origins of aneuploidy in the human blastocyst

Preimplantation genetic testing commonly employs simplistic copy-number analyses to screen for aneuploidy in blastocyst trophectoderm biopsies. Interpreting intermediate copy number alone as evidence of mosaicism has led to suboptimal estimation of its prevalence. Because mosaicism originates from mitotic nondisjunction, utilizing SNP microarray technology to identify the cell-division origins of aneuploidy might provide a more accurate estimation of its prevalence. The present study develops and validates a method of determining the cell-division origin of aneuploidy in the human blastocyst by using both genotyping and copy-number data in parallel. The concordance of predicted origins with expected results was demonstrated in a series of truth models (99%-100%). This included determination of X chromosome origins from a subset of normal male embryos, determination of the origins of translocation chromosome-related imbalances via embryos from couples with structural rearrangements, and prediction of either mitotic or meiotic origins via multiple rebiopsies of embryos with aneuploidy. In a cohort of blastocysts with parental DNA (n = 2,277), 71% were euploid, 27% were meiotic aneuploid, and 2% were mitotic aneuploid, indicating a low frequency of bona fide mosaicism in the human blastocyst (mean maternal age: 34.4). Chromosome-specific trisomies in the blastocyst were also consistent with observations previously established in products of conception. The ability to accurately identify mitotic-origin aneuploidy in the blastocyst could benefit and better inform individuals whose IVF cycle results in all aneuploid embryos. Clinical trials with this methodology might also help provide a definitive answer regarding the reproductive potential of bona fide mosaic embryos.

Reproductive options in mitochondrial disease

Mitochondrial diseases require customized approaches for reproductive counseling, addressing differences in recurrence risks and reproductive options. The majority of mitochondrial diseases is caused by mutations in nuclear genes and segregate in a Mendelian way. Prenatal diagnosis (PND) or preimplantation genetic testing (PGT) are available to prevent the birth of another severely affected child. In at least 15%-25% of cases, mitochondrial diseases are caused by mitochondrial DNA (mtDNA) mutations, which can occur de novo (25%) or be maternally inherited. For de novo mtDNA mutations, the recurrence risk is low and PND can be offered for reassurance. For maternally inherited, heteroplasmic mtDNA mutations, the recurrence risk is often unpredictable, due to the mitochondrial bottleneck. PND for mtDNA mutations is technically possible, but often not applicable given limitations in predicting the phenotype. Another option for preventing the transmission of mtDNA diseases is PGT. Embryos with mutant load below the expression threshold are being transferred. Oocyte donation is another safe option to prevent the transmission of mtDNA disease to a future child for couples who reject PGT. Recently, mitochondrial replacement therapy (MRT) became available for clinical application as an alternative to prevent the transmission of heteroplasmic and homoplasmic mtDNA mutations.

Preimplantation genetic testing for aneuploidy: helpful but not a first choice

PURPOSE

This retrospective cohort study aimed to assess and compare the outcomes between cumulative live birth of patients with and without PGT-A and also between prior unsuccessful IVF cycles and PGT-A cycles among patients who experienced IVF but without live birth delivery, and to clarify the effective usage of PGT-A as an in vitro fertilization (IVF) add-on.

METHODS

A total of 2113 females undergoing IVF with at least one blastocyst were reviewed. Patients in the PGT-A and non-PGT-A groups were further categorized into first-time IVF and prior unsuccessful IVF groups (previous IVF experience but without live birth delivery).

RESULTS

In the PGT-A group, there were additional oocyte retrieval cycles, fewer transfer cycles per patient, higher clinical pregnancy rates per embryo transfer, and lower miscarriage rates per clinical pregnancy as compared to the non-PGT-A group, all showing significant differences. However, the first-time IVF group with PGT-A had a significantly longer duration from the first oocyte retrieval to the first live birth delivery (LBD) and a significantly lower LBD rate per patient than the non-PGT-A group. The cumulative probability for a first LBD with PGT-A was inferior in the first-time IVF group for women < 35 years, marginally superior in the prior unsuccessful IVF group of women aged 38-40 years, and similar for other groups.

CONCLUSION

PGT-A should not be recommended to all patients; however, if the first IVF treatment failed, PGT-A may reduce the patient's burden regardless of age.

Fatty acid supplementation into warming solutions improves pregnancy outcomes after single vitrified-warmed cleavage stage embryo transfers

Purpose

This study aimed to examine the embryonic development of human 4-cell stage embryos after warming with fatty acids (FAs) and to assess the pregnancy outcomes after single vitrified-warmed cleavage stage embryo transfers (SVCTs).

Methods

Experimental study: A total of 217 discarded, vitrified human 4-cell stage embryos donated for research by consenting couples were used. The embryos were warmed using the fatty acid (FA)-supplemented solutions (FA group) or nonsupplemented solutions (control group). The developmental rate, morphokinetics, and outgrowth competence were analyzed. Clinical study: The treatment records of women undergoing SVCT in natural cycles between April and September 2022 were retrospectively analyzed (April-June 2022, control group; July-September 2022, FA group).

Results

Experimental study: The rate of morphologically good blastocysts was significantly higher in the FA group than in the control group (p = 0.0302). The morphokinetics during cleavage, morula, and blastocyst stages were comparable between the groups. The outgrowth was significantly increased in the FA group (p = 0.0438). Clinical study: The rates of implantation, clinical pregnancy, and ongoing pregnancy after SVCTs were significantly increased in the FA group (p = 0.0223-0.0281).

Conclusions

Fatty acid-supplemented warming solutions effectively improve embryo development to the blastocyst stage and pregnancy outcomes after SVCTs.

Preimplantation genetic testing for aneuploidy: challenges in clinical practice

Preimplantation genetic testing for aneuploidy (PGT-A) has been used widely during in vitro fertilization procedures in assisted reproductive centers throughout the world. Despite its wide use, concerns arise from the use of PGT-A technology in clinical decision-making. We address knowledge gaps in PGT-A, summarizing major challenges and current professional guidelines. First, PGT-A is a screening test and not a diagnostic test. Second, mosaicism is much higher in the blastocyst stage from PGT-A than had been recognized previously and a mosaic embryo may not accurately represent the genetic disease risk for future fetal disorders. Third, PGT-A was not validated clinically before use in patients; the best use of this technology for selected age-groups remains uncertain. Given these gaps, we believe that current professional policies relying on industry-self-regulation are insufficient. In the USA, the Food and Drug Administration may be the most appropriate agency to provide more definitive guidelines and regulations that are needed for better practice.

Comment on the recent PGDIS Position Statement on the Transfer of Mosaic Embryos 2021

The worldwide demand of preimplantation genetic testing for aneuploidy (PGT-A) is still growing. However, chromosomal mosaic results greatly challenge the clinical practice. The recently published PGDIS Position Statement on the Transfer of Mosaic Embryos is the third PGDIS position statement on how to deal with embryos diagnosed as chromosomal mosaics (CM) and, one of many attempts of different societies and working groups to provide a guideline for clinicians, laboratories, clinics, and genetic counselors. But still, as in previous statements, many issues remained unresolved. Moreover, from our point of view, the question how to deal with embryos diagnosed as CM, consisting of two or more karyological cell lines cannot be separated from all the other aspects of PGT-A including its accuracy. The paucity of clearcut indications for PGT-A and evidence of benefit as well as an overall cost-benefit assessment is given below.

A SART data cost-effectiveness analysis of planned oocyte cryopreservation versus in vitro fertilization with preimplantation genetic testing for aneuploidy considering ideal family size

OBJECTIVE

To determine the cost-effectiveness of planned oocyte cryopreservation (OC) as a strategy for delayed childbearing to achieve 1 or 2 live births (LB) compared with in vitro fertilization (IVF) and preimplantation genetic testing for aneuploidy (PGT-A) at advanced reproductive age.

DESIGN

Decision tree model with sensitivity analyses using data from the Society for Assisted Reproductive Technology Clinical Outcome Reporting System and other clinical sources.

SETTING

Not applicable.

PATIENT(S)

A data-driven simulated cohort of patients desiring delayed childbearing with an ideal family size of 1 or 2 LB.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Probability of achieving ≥1 or 2 LB, average and maximum cost per patient, cost per percentage point increase in chance of LB, and population-level cost/LB.

RESULT(S)

For those desiring 1 LB, planned OC at age 33 with warming at age 43 decreased the average total cost per patient from $62,308 to $30,333 and increased the likelihood of LB from 50% to 73% when compared with no OC with up to 3 cycles of IVF/PGT-A at age 43. For those desiring 2 LB, 2 cycles of OC at age 33 and warming at age 40 yielded the lowest cost per patient and highest likelihood of achieving 2 LB ($51,250 and 77%, respectively) when compared withpursuing only 1 cycle of OC ($75,373 and 61%, respectively), no OC and IVF/PGT-A with embryo banking ($79,728 and 48%, respectively), or no OC and IVF/PGT-A without embryo banking ($79,057 and 19%, respectively). Sensitivity analyses showed that OC remained cost-effective across a wide range of ages at cryopreservation. For 1 LB, OC achieved the highest likelihood of success when pursued before age 32 and remained more effective than IVF/PGT-A when pursued before age 39, and for 2 LB, 2 cycles of OC achieved the highest likelihood of success when pursued before age 31 and remained more effective than IVF/PGT-A when pursued before age 39.

CONCLUSION(S)

Among patients planning to postpone childbearing, OC is cost-effective and increases the odds of achieving 1 or 2 LB when compared with IVF/PGT-A at a more advanced reproductive age.

Clinical Outcome, Socioeconomic Status and Psychological Constrains of Patients Undergoing Preimplantation Genetic Testing (PGT) in Northern Greece

Background and objectives: Preimplantation genetic testing (PGT) offers patients the possibility of having a healthy baby free of chromosomal or genetic disorders. The present study focuses on the application of PGT for patients located in Northern Greece, investigating their clinical outcomes, their motives, and their overall physical and emotional experience during the treatment, in association with their socioeconomic background. Materials and Methods: Couples who underwent PGT for a monogenic condition (PGT-M, n = 19 cycles) or aneuploidy (PGT-A, n = 22 cycles) participated in the study. Fertilization, implantation, and pregnancy rates were recorded for all cycles. The couples were asked to fill in a questionnaire about the consultation they had received prior to treatment, their sociodemographic information, and the psychological impact PGT had on both the female and male partner. Results: The fertilization, implantation, and ongoing pregnancy rates for the PGT-M and PGT-A cycles were 81.3%, 70.6%, and 52.9%, and 78.2%, 64.3%, and 57.1%, respectively. Females experienced more intense physical pain than their male partners while psychological pain was encountered by both partners and occasionally in higher instances in males. No typical socioeconomic background of the patients referred for PGT in Northern Greece was noticed. Conclusion: PGT is an attractive alternative to prenatal diagnosis (PND), aiming to establisha healthy pregnancy by identifying and avoiding the transfer of chromosomally or genetically abnormal embryos to the uterus. Although the benefits of PGT were well-received by all patients undergoing the procedure, psychological pain was evident and especially prominent in patients with a previous affected child or no normal embryos for transfer. Holistic counseling is of utmost importance in order to make patients' experience during their journey to have a healthy baby less emotionally demanding and help them make the right choices for the future.

ESHRE survey results and good practice recommendations on managing chromosomal mosaicism

STUDY QUESTION

How should ART/preimplantation genetic testing (PGT) centres manage the detection of chromosomal mosaicism following PGT?

SUMMARY ANSWER

Thirty good practice recommendations were formulated that can be used by ART/PGT centres as a basis for their own policy with regards to the management of ‘mosaic’ embryos.

WHAT IS KNOWN ALREADY

The use of comprehensive chromosome screening technologies has provided a variety of data on the incidence of chromosomal mosaicism at the preimplantation stage of development and evidence is accumulating that clarifies the clinical outcomes after transfer of embryos with putative mosaic results, with regards to implantation, miscarriage and live birth rates, and neonatal outcomes.

STUDY DESIGN, SIZE, DURATION

This document was developed according to a predefined methodology for ESHRE good practice recommendations. Recommendations are supported by data from the literature, a large survey evaluating current practice and published guidance documents. The literature search was performed using PubMed and focused on studies published between 2010 and 2022. The survey was performed through a web-based questionnaire distributed to members of the ESHRE special interest groups (SIG) Reproductive Genetics and Embryology, and the ESHRE PGT Consortium members. It included questions on ART and PGT, reporting, embryo transfer policy and follow-up of transfers. The final dataset represents 239 centres.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The working group (WG) included 16 members with expertise on the ART/PGT process and chromosomal mosaicism. The recommendations for clinical practice were formulated based on the expert opinion of the WG, while taking into consideration the published data and results of the survey.

MAIN RESULTS AND THE ROLE OF CHANCE

Eighty percent of centres that biopsy three or more cells report mosaicism, even though only 66.9% of all centres have validated their technology and only 61.8% of these have validated specifically for the calling of chromosomal mosaicism. The criteria for designating mosaicism, reporting and transfer policies vary significantly across the centres replying to the survey. The WG formulated recommendations on how to manage the detection of chromosomal mosaicism in clinical practice, considering validation, risk assessment, designating and reporting mosaicism, embryo transfer policies, prenatal testing and follow-up. Guidance is also provided on the essential elements that should constitute the consent forms and the genetic report, and that should be covered in genetic counselling. As there are several unknowns in chromosomal mosaicism, it is recommended that PGT centres monitor emerging data on the topic and adapt or refine their policy whenever new insights are available from evidence.

LIMITATIONS, REASONS FOR CAUTION

Rather than providing instant standardized advice, the recommendations should help ART/PGT centres in developing their own policy towards the management of putative mosaic embryos in clinical practice.

WIDER IMPLICATIONS OF THE FINDINGS

This document will help facilitate a more knowledge-based approach for dealing with chromosomal mosaicism in different centres. In addition to recommendations for clinical practice, recommendations for future research were formulated. Following up on these will direct research towards existing research gaps with direct translation to clinical practice. Emerging data will help in improving guidance, and a more evidence-based approach of managing chromosomal mosaicism.

STUDY FUNDING/COMPETING INTEREST(S)

The WG received technical support from ESHRE. M.D.R. participated in the EQA special advisory group, outside the submitted work, and is the chair of the PGT WG of the Belgian society for human genetics. D.W. declared receiving salary from Juno Genetics, UK. A.C. is an employee of Igenomix, Italy and C.R. is an employee of Igenomix, Spain. C.S. received a research grant from FWO, Belgium, not related to the submitted work. I.S. declared being a Co-founder of IVFvision Ltd, UK. J.R.V. declared patents related to ‘Methods for haplotyping single-cells’ and ‘Haplotyping and copy number typing using polymorphic variant allelic frequencies’, and being a board member of Preimplantation Genetic Diagnosis International Society (PGDIS) and International Society for Prenatal Diagnosis (ISPD). K.S. reported being Chair-elect of ESHRE. The other authors had nothing to disclose.

DISCLAIMER

This Good Practice Recommendations (GPR) document represents the views of ESHRE, which are the result of consensus between the relevant ESHRE stakeholders and are based on the scientific evidence available at the time of preparation. 

ESHRE GPRs should be used for information and educational purposes. They should not be interpreted as setting a standard of care or be deemed inclusive of all proper methods of care, or be exclusive of other methods of care reasonably directed to obtaining the same results. They do not replace the need for application of clinical judgement to each individual presentation, or variations based on locality and facility type. 

Furthermore, ESHRE GPRs do not constitute or imply the endorsement, or favouring, of any of the included technologies by ESHRE. 

Morphological and morphokinetic associations with aneuploidy: a systematic review and meta-analysis

BACKGROUND

A time lapse system (TLS) is utilized in some fertility clinics with the aim of predicting embryo viability and chance of live birth during IVF. It has been hypothesized that aneuploid embryos display altered morphokinetics as a consequence of their abnormal chromosome complement. Since aneuploidy is one of the fundamental reasons for IVF failure and miscarriage, attention has focused on utilizing morphokinetics to develop models to non-invasively risk stratify embryos for ploidy status. This could avoid or reduce the costs associated with pre-implantation genetic testing for aneuploidy (PGT-A). Furthermore, TLS have provided an understanding of the true prevalence of other dysmorphisms. Hypothetically, the incorporation of morphological features into a model could act synergistically, improving a model's discriminative ability to predict ploidy status.

OBJECTIVE AND RATIONALE

The aim of this systematic review and meta-analysis was to investigate associations between ploidy status and morphokinetic or morphological features commonly denoted on a TLS. This will determine the feasibility of a prediction model for euploidy and summarize the most useful prognostic markers to be included in model development.

SEARCH METHODS

Five separate searches were conducted in Medline, Embase, PubMed and Cinahl from inception to 1 July 2021. Search terms and word variants included, among others, PGT-A, ploidy, morphokinetics and time lapse, and the latter were successively substituted for the following morphological parameters: fragmentation, multinucleation, abnormal cleavage and contraction. Studies were limited to human studies.

OUTCOMES

Overall, 58 studies were included incorporating over 40 000 embryos. All except one study had a moderate risk of bias in at least one domain when assessed by the quality in prognostic studies tool. Ten morphokinetic variables were significantly delayed in aneuploid embryos. When excluding studies using less reliable genetic technologies, the most notable variables were: time to eight cells (t8, 1.13 h, 95% CI: 0.21-2.05; three studies; n = 742; I2 = 0%), t9 (2.27 h, 95% CI: 0.5-4.03; two studies; n = 671; I2 = 33%), time to formation of a full blastocyst (tB, 1.99 h, 95% CI 0.15-3.81; four studies; n = 1640; I2 = 76%) and time to expanded blastocyst (tEB, 2.35 h, 95% CI: 0.06-4.63; four studies; n = 1640; I2 = 83%). There is potentially some prognostic potential in the degree of fragmentation, multinucleation persisting to the four-cell stage and frequency of embryo contractions. Reverse cleavage was associated with euploidy in this meta-analysis; however, this article argues that these are likely spurious results requiring further investigation. There was no association with direct unequal cleavage in an embryo that progressed to a blastocyst, or with multinucleation assessed on Day 2 or at the two-cell stage. However, owing to heterogeneous results and poor-quality evidence, associations between these morphological components needs to be investigated further before conclusions can be reliably drawn.

WIDER IMPLICATIONS

This first systematic review and meta-analysis of morphological and morphokinetic associations with ploidy status demonstrates the most useful morphokinetic variables, namely t8, t9 and tEB to be included in future model development. There is considerable variability within aneuploid and euploid embryos making definitively classifying them impossible; however, it is feasible that embryos could be prioritized for biopsy. Furthermore, these results support the mechanism by which algorithms for live birth may have predictive ability, suggesting aneuploidy causes delayed cytokinesis. We highlight significant heterogeneity in our results secondary to local conditions and diverse patient populations, therefore calling for future models to be robustly developed and tested in-house. If successful, such a model would constitute a meaningful breakthrough when accessing PGT-A is unsuitable for couples.

Disrupting the biological clock: Fertility benefits, egg freezing and proactive fertility management

In the last decade, the in-vitro fertilization (IVF) sector has witnessed a shift from so-called 'reactive IVF' to a new model of proactive fertility care. Whereas IVF was traditionally developed to treat people who found they were unable to conceive, the indication for IVF has broadened significantly to include a much wider group of potential patients through a new focus on proactive treatment of future (in)fertilities. This shift combines a number of new trends pertaining to preservation, prediction, private equity and platformization, all of which have gained influence in contemporary assisted reproduction. This article focuses on the emergence of company-sponsored fertility benefits, which combines each of these trends. Whereas fertility benefits - especially egg freezing insurance - have primarily been discussed in terms of women's empowerment or disenfranchisement, this article instead calls attention to the discursive, clinical and infrastructural shifts in contemporary assisted reproduction that have emerged with the rising popularity of these benefits. The analysis addresses these underdiscussed aspects of fertility benefits by focusing on the dynamics of demand; the shifts in the rationalization of intensified treatment pathways in the face of new reimbursement practices; and the online, platform-based infrastructures that are built to provide these treatments. In doing so, it analyses how this remaking of fertility towards an ethos of proactive fertility management reflects broader capitalist tailwinds.

The changing world of IVF: the pros and cons of new business models offering assisted reproductive technologies

This analysis contrasts traditional not-for-profit academic with new corporate practices of reproductive medicine and offers an assessment of risks to quality of patient care with investors entering the for-profit reproductive medicine market. Large corporate enterprises may have a global impact on access to care while at the same time is putting at risk the training of the next generation of reproductive medicine specialists.

Non-Assisted Hatching Trophectoderm Biopsy Does Not Increase The Risks of Most Adverse Maternal and Neonatal Outcome and May Be More Practical for Busy Clinics: Evidence From China

OBJECTIVE

This study was conducted in order to investigate whether non-assisted hatching trophectoderm (TE) biopsy increases the risks of adverse perinatal outcomes in livebirths following elective single cryopreserved-thawed blastocyst transfer.

PATIENTS AND METHODS

A total of 5,412 cycles from 4,908 women who achieved singleton livebirths between 2013 and 2019 were included in this retrospective cohort study. All embryos in this study were fertilized by intracytoplasmic sperm injection (ICSI) and cryopreserved through vitrification. The main intervention is to open the zona pellucida (ZP) of day 5/6 blastocyst immediately for biopsy without pre-assisted hatching. The main outcome measures are the common maternal and neonatal outcomes, including hypertensive disorders of pregnancy (HDPs), gestational diabetes mellitus (GDM), abnormal placentation, abnormalities in umbilical cord and amniotic fluid, preterm birth, cesarean section, low birth weight, postpartum hemorrhage, and prolonged hospital stay (both mothers and infants). The generalized estimation equation (GEE) was used to control the effects of repeated measurements. The non-conditional logistic regression model was used to examine the associations between embryo biopsy status and each adverse perinatal event. Given that the selection bias and changes in learning curve might affect the results, we selected 1,086 similar (matching tolerance = 0.01) cycles from the ICSI group via propensity score matching (PSM) for second comparisons and adjustment (conditional logistic regression).

RESULTS

After adjusting for confounders, we confirmed that the non-assisted hatching protocol did not increase the risks of most adverse maternal and neonatal outcomes. Despite this, there were increased risks of GDM (aOR: 1.522, 95% CI: 1.141-2.031) and umbilical cord abnormalities (aOR: 11.539, 95% CI: 1.199-111.067) in the biopsy group. In the second comparisons after PSM, GDM incidence in the biopsy group was still higher (7.26% vs. 5.16%, P = 0.042), yet all measurement outcomes were equally likely to occur in both groups after the second adjustment.

CONCLUSIONS

The non-assisted hatching TE biopsy does not increase the risks of most adverse perinatal outcomes. However, there is a higher GDM incidence in the biopsy group, and this association warrants further study. Considering its safety and simplicity, the non-assisted hatching protocol has the potential to become the preferred option for TE biopsy, especially in busy clinics and IVF laboratories.

Analysis of IVF live birth outcomes with and without preimplantation genetic testing for aneuploidy (PGT-A): UK Human Fertilisation and Embryology Authority data collection 2016-2018

Purpose

To examine the live birth and other outcomes reported with and without preimplantation genetic testing for aneuploidy (PGT-A) in the United Kingdom (UK) Human Embryology and Fertilization Authority (HFEA) data collection.

Methods

A retrospective cohort analysis was conducted following freedom of information (FoI) requests to the HFEA for the PGT-A and non-PGT-A cycle outcomes for 2016–2018. Statistical analysis of differences between PGT-A and non-PGT-A cycles was performed. Other than grouping by maternal age, no further confounders were controlled for; fresh and frozen transfers were included.

Results

Outcomes collected between 2016 and 2018 included total number of cycles, cycles with no embryo transfer, total number of embryos transferred, live birth rate (LBR) per embryo transferred and live birth rate per treatment cycle. Data was available for 2464 PGT-A out of a total 190,010 cycles. LBR per embryo transferred and LBR per treatment cycle (including cycles with no transfer) were significantly higher for all PGT-A vs non-PGT-A age groups (including under 35), with nearly all single embryo transfers (SET) after PGT-A (significantly more in non-PGT-A) and a reduced number of transfers per live birth particularly for cycles with maternal age over 40 years.

Conclusion

The retrospective study provides strong evidence for the benefits of PGT-A in terms of live births per embryo transferred and per cycle started but is limited in terms of matching PGT-A and non-PGT-A cohorts (e.g. in future studies, other confounders could be controlled for). This data challenges the HFEA “red traffic light” guidance that states there is “no evidence that PGT-A is effective or safe” and hence suggests the statement be revisited in the light of this and other new data.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10815-021-02349-0.

Antifreeze proteins for low-temperature preservation in reproductive medicine: A systematic review over the last three decades

Antifreeze proteins (AFPs) are synthesized by diverse non-mammalian species, allowing them to survive in severely cold environments. Since the 1990s, the scientific literature reports their use for low-temperature preservation of germplasm. The aim of this systematic review was to compile available scientific evidence regarding the use of AFP for low-temperature preservation of several reproductive specimens. Internet databases were consulted using the terms: "antifreeze protein" OR "AFP" OR "antifreeze glycoprotein" OR "AFGP" OR "ice-binding protein" OR "IBP" OR "thermal hysteresis protein" AND "cryopreservation". From 56 articles, 87 experiments testing AFPs in low-temperature preservation of gametes, embryos or reproductive tissues/cells were fully analyzed and outcomes were annotated. A positive outcome was considered as a statistically significant improvement on any parameter evaluated after low-temperature preservation with AFP, whereas a negative outcome included worsening of any evaluated parameter, in comparison to untreated groups or groups treated with a lower concentration of AFP. The findings indicated that research on the use of AFP as a cryoprotectant for reproductive specimens has increased markedly over the past decade. Some experiments reported both positive and negative results, which depended, on AFP concentration in the preservation media. Variation in the outcomes associated with species was also observed. Among the 66 experiments conducted in mammals, 77.3% resulted in positive, and 28.8% in negative outcomes after the use of AFP. In fishes, positive and negative outcomes were observed in 71.4% and 33.3% of 21 experiments, respectively. Most positive outcomes included preserving cell post-warming survival. The beneficial effect of AFP supports its use in cryobiological approaches used in human and veterinary medicines and animal protein industry. Moreover, combination of different AFP types, or AFP with antioxidants, or even the use of AFP-biosimilar, comprise some promising approaches to be further explored in cryopreservation.

The impact of estradiol on pregnancy outcomes in letrozole-stimulated frozen embryo transfer cycles

Objective

To assess the impact of low estradiol (E2) levels in letrozole-stimulated frozen embryo transfer (FET) cycles on pregnancy and neonatal outcomes.

Design

Retrospective cohort.

Setting

University-affiliated fertility center.

Patients

All patients who underwent letrozole-stimulated FET cycles from January 2017 to April 2020 (n = 217). The "Low E2" group was defined as those with E2 serum levels on the day of trigger <10th percentile level (E2 <91.16 pg/mL, n = 22) and the "Normal E2" group was defined as those with E2 serum levels ≥10th percentile level (E2 ≥91.16 pg/mL, n = 195).

Interventions

None.

Main Outcome Measures

Pregnancy outcomes including rates of clinical pregnancy, clinical miscarriage, and live birth. Neonatal outcomes including gestational age at delivery, birth weight, and Apgar score.

Results

The mean ± SD estradiol level was 66.8 ± 14.8 pg/mL for the "Low E2" group compared with 366.3 ± 322.1 pg/mL for the "Normal E2" group. There were otherwise no substantial differences in cycle characteristics such as endometrial thickness on the day of ovulation trigger and progesterone levels in early pregnancy. The "Low E2" group had a significantly higher clinical miscarriage rate (36.4% vs. 8.8%, adjusted odds ratio 8.06) and lower live birth rate (31.8% vs. 57.9%, adjusted odds ratio 0.28). Neonatal outcomes such as gestational age at delivery, mean birth weight, Apgar scores, and incidence of newborn complications were not clinically different between the groups.

Conclusion

Low E2 levels were associated with a significantly higher miscarriage rate and lower live birth rate, suggesting that E2 levels in the follicular phase may have an effect on cycle outcomes. Given the rise in use of FET, further studies are needed to confirm our findings and understand the mechanisms.

The clinical application of single-sperm-based single-nucleotide polymorphism haplotyping for PGT of patients with genetic diseases

RESEARCH QUESTION

Is there a simple and effective method for male patients with genetic disorders in families with no identified haplotype and with Robertsonian translocations to avoid the transfer of embryos carrying translocated chromosomes?

DESIGN

Single spermatozoa were separated to identify by next-generation sequencing (NGS) those that were genetically abnormal, to establish a sperm-based single-nucleotide polymorphism (SNP) haplotype. Blastocysts that developed to day 5 or 6 were then biopsied for whole genome amplification and screening for chromosomal aneuploidy. Normal embryos were selected by comparison with a single-sperm-based SNP haplotype and were transferred. The results were verified by second trimester amniocentesis.

RESULTS

Two blastocysts obtained from patients with neurofibroma type 1 (NF1) were found to be normal after NGS according to single-sperm-based SNP haplotype analysis (13 SNP sites). Three and one blastocysts, respectively, were obtained from the patients with Robertsonian translocation. Blastocysts B9 and B7 were found to be normal after NGS according to the single-sperm-based SNP haplotype analysis (12 and 13 SNP sites selected on chromosomes 14 and 22 for the first patient; 12 and 9 SNP sites selected on chromosomes 13 and 14 for the second patient). Successful pregnancies after blastocyst transfer occurred in all three patients. The identification of embryos was verified by mid-trimester amniocentesis. All three patient couples successfully delivered healthy babies.

CONCLUSION

This study preliminarily summarized the process of single-sperm-based SNP haplotyping, which could be applied as preimplantation genetic testing for male patients without identified disease-causing haplotypes and with Robertsonian translocations.

Embryo biopsy and maternal and neonatal outcomes following cryopreserved-thawed single embryo transfer

BACKGROUND

Contemporary embryo biopsy in the United States involves the removal of several cells from a blastocyst that would become the placenta for preimplantation genetic testing. Embryos are then cryopreserved while patients await biopsy results, with transfers occurring in a subsequent cycle as a single frozen-thawed embryo transfer, if euploid.

OBJECTIVE

We sought to determine if removal of these cells for preimplantation genetic testing was associated with adverse obstetrical or neonatal outcomes after frozen-thawed single embryo transfer.

STUDY DESIGN

We linked assisted reproductive technology surveillance data from the Society for Assisted Reproductive Technology Clinic Outcome Reporting System to birth certificates and maternal and neonatal hospitalization discharge diagnoses in Massachusetts from 2014 to 2017, considering only singleton births after frozen-thawed single embryo transfers. We compared outcomes of cycles having embryo biopsy (n=585) to those having no biopsy (n=2191) using chi-square for categorical and binary variables and logistic regression for adjusted odds ratios and 95% confidence intervals, adjusting for mother's age, race, education, parity, body mass index, birth year, insurance, and all infertility diagnoses.

RESULTS

Considering no biopsy as the reference, there was no difference between groups with respect to preeclampsia (adjusted odds ratio, 0.82; 95% confidence interval, 0.42-1.61; P=.5685); pregnancy-induced hypertension (adjusted odds ratio, 0.85; 95% confidence interval, 0.46-1.59; P=.6146); placental disorders, including placental abruption, placenta previa, placenta accreta, placenta increta, and placenta percreta (adjusted odds ratio, 1.16; 95% confidence interval, 0.60-2.24; P=.6675); preterm birth (adjusted odds ratio, 1.22; 95% confidence interval 0.73-2.03; P=.4418); low birthweight (adjusted odds ratio, 1.12; 95% confidence interval, 0.58-2.15; P=.7355); cesarean delivery (adjusted odds ratio, 1.04; 95% confidence interval, 0.79-1.38; P=.7762); or gestational diabetes mellitus (adjusted odds ratio, 0.83; 95% confidence interval, 0.50-1.38; P=.4734). In addition, there was no difference between the groups for prolonged hospital stay for mothers (adjusted odds ratio, 1.23; 95% confidence interval, 0.83-1.80; P=.3014) or for infants (95% confidence interval, 1.29; 95% confidence interval, 0.72-2.29; P=.3923).

CONCLUSION

Embryo biopsy for preimplantation genetic testing does not increase the odds for diagnoses related to placentation (preeclampsia, pregnancy-related hypertension, placental disorders, preterm delivery, or low birthweight), maternal conditions (gestational diabetes mellitus), or maternal or infant length of stay after delivery.

The role of preimplantation genetic testing for aneuploidy in a good prognosis IVF population across different age groups

Preimplantation genetic testing for aneuploidy is associated with increased pregnancy success and reduced miscarriage in women 35 years and older when embryos are available for transfer. In this retrospective cohort study our objective was to evaluate if this holds true in good prognosis patients and across all age groups. Data were obtained from the Society for Assisted Reproductive Technology between 2014-2015. We included only the first single frozen embryo transfer where indication for corresponding 'stimulation/freeze-all cycle' was for reducing risk of ovarian hyperstimulation syndrome and performance of PGT-A for selecting euploid embryos. Our main outcomes were live birth and miscarriage rates. Among <35 age group, no difference in LBR was observed between cycles who underwent single embryo FET using non-PGT-A tested vs. tested embryos (51.7% vs. 50.9%, aOR 1.03, 95% CI 0.87-1.21). Additionally, the miscarriage rates (8.7% vs. 8.8%, aOR 0.97, 95% CI 0.72-1.30) were not different. Among 35-37 years old, no difference was observed between non-PGT-A tested and tested groups in LBR (50.4% vs. 54.7%, aOR 1.26, 95% CI 0.96-1.67) or miscarriage rates (8.3% vs. 10%; aOR 1.11, 95% CI 0.68-1.82). Similarly, among > 37 year old, no difference was observed between non-PGT-A tested and tested groups in LBR (48.1% vs. 53.2%, aOR 1.27, 95% CI 0.8-2.02) and miscarriage rates (6.2% vs. 8.5%, aOR1.34, 95% CI 0.52-3.43). To conclude, PGT-A tested embryos did not improve LBR and miscarriage rates in a good prognosis IVF population across all age groups.Abbreviations: PGT-A: preimplantation genetic testing for aneuploidy; FET: frozen embryo transfer; LBR: live birth rate; OHSS: ovarian hyperstimulation syndrome; SART: society for assisted reproductive technology.

Impact of preimplantation genetic testing on obstetric and neonatal outcomes: a systematic review and meta-analysis

OBJECTIVE

To investigate whether preimplantation genetic testing (PGT) increases the risk of adverse obstetric and neonatal outcomes.

DESIGN

Systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Pregnancies achieved after PGT or in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI).

INTERVENTION(S)

Systematic search of databases until December 2020 with cross-checking of references from relevant articles in English.

MAIN OUTCOME MEASURE(S)

Obstetric and neonatal outcomes after PGT and IVF/ICSI, including mean birth weight, low birth weight, very low birth weight (VLBW), mean gestational age at birth, preterm birth, very preterm birth, birth defects, intrauterine growth retardation (IUGR), sex ratio, cesarean section, hypertensive disorders of pregnancy, gestational diabetes mellitus, placenta disorder (placenta previa, placenta abruption, placenta accreta), and preterm premature rupture of membranes.

RESULT(S)

Ultimately, a total of 785,445 participants were enrolled in this meta-analysis, and these participants were divided into a PGT group (n = 54,294) and an IVF/ICSI group (n = 731,151). The PGT pregnancies had lower rates of low birth weight (risk ratio [RR] 0.85, 95% confidence interval [CI] 0.75 to 0.98), VLBW (RR 0.52, 95% CI 0.33 to 0.81), and very preterm births (RR 0.55, 95% CI 0.42 to 0.70) than those of IVF/ICSI pregnancies. However, the PGT group had a higher rate of the obstetric outcome of hypertensive disorders of pregnancy (RR 1.30, 95% CI 1.08 to 1.57). The PGT did not increase the risk of other adverse obstetric and neonatal outcomes, such as those associated with mean birth weight, mean gestational age at birth, birth defects, IUGR, sex ratio, cesarean section, gestational diabetes mellitus, placental disorder (placenta previa, placenta abruption, placenta accreta), or preterm premature rupture of membranes. We performed subgroup analysis with only blastocyst biopsies and found that PGT with blastocyst biopsies was associated with a lower rate of VLBW (RR 0.55, 95% CI 0.31 to 0.95). The PGT with blastocyst biopsies did not increase the risk of other adverse obstetric and neonatal outcomes. Additionally, we performed subgroup analysis with only frozen-thawed embryo transfer cycles, and we found that PGT pregnancies were associated with a lower rate of VLBW (RR 0.55, 95% CI 0.31 to 0.97), a lower rate of cesarean birth (RR 0.90, 95% CI 0.82 to 0.99), a higher rate of preterm birth (RR 1.10, 95% CI 1.02 to 1.18), and a higher rate of IUGR (RR 1.21, 95% CI 1.06 to 1.38) than those of IVF/ICSI pregnancies. The PGT with frozen-thawed embryo transfer did not increase the risk of other adverse obstetric and neonatal outcomes.

CONCLUSION(S)

The pooled analysis suggested that PGT did not increase the risk of adverse obstetric outcomes. The association between PGT and a higher risk of IUGR requires further investigation.

Maternal and neonatal outcomes following blastocyst biopsy for PGT in single vitrified-warmed embryo transfer cycles

RESEARCH QUESTION

Does blastocyst biopsy for preimplantation genetic testing (PGT) increase the risk of adverse maternal and neonatal outcomes?

STUDY DESIGN

Retrospective cohort study of 5097 single vitrified-warmed blastocyst transfer cycles from January 2016 to December 2018, with 2061 cycles in the biopsied group and 3036 cycles in the unbiopsied group enrolled in the analyses. Maternal and neonatal outcomes were compared between the two groups.

RESULTS

The live birth rate in the biopsied group (41.1%) was significantly higher than that in the unbiopsied group (35.6%, adjusted odds ratio [aOR] 1.27, 95% confidence interval [CI] 1.05-1.54, P = 0.012) after adjusting for maternal age, maternal body mass index, gravidity, parity, infertility diagnosis, timing of blastocyst transfer, blastocyst quality, regimen of endometrial preparation, endometrial thickness before transfer and treatment year. The rates of total pregnancy loss (25.4% versus 32.2%, aOR 0.69, 95% CI 0.52-0.91, P = 0.008) and early miscarriage (12.1% versus 17.3%, aOR 0.56, 95% CI 0.38-0.83, P = 0.004) were significantly lower in the biopsied group than in the unbiopsied group. No significant differences were found in sex ratio or the risks of hypertensive disorders in pregnancy, diabetes in pregnancy, placenta previa, preterm premature rupture of membranes, low birthweight, very low birthweight, macrosomia, small for gestational age, large for gestational age or birth defects between the two groups. When the subgroup analyses were conducted based on different types of PGT, similar patterns were found for all types.

CONCLUSION

Blastocyst biopsy might not increase the risks of adverse maternal and neonatal outcomes in the short term.

Preimplantation Genetic Testing for Aneuploidy: A Review of the Evidence

Preimplantation genetic testing for aneuploidy was developed as an invasive embryo-selection technique and is extensively used in in vitro fertilization (IVF) cycles. Around 95,000 preimplantation genetic testing cycles were carried out in the United States between 2014 and 2016, the majority of which were performed for aneuploidy. The objective of preimplantation genetic testing for aneuploidy is to select for transfer a euploid embryo, after embryo biopsy and cytogenetic analysis. The current technique consists of applying comprehensive chromosome screening on trophectoderm cells after blastocyst-stage embryo biopsy. This article reviews all the published randomized controlled trials on preimplantation genetic testing for aneuploidy with comprehensive chromosome screening and comments on the subject of embryo mosaicism detected by this technique. Most of these trials have been criticized because they only included good prognosis patients having normal ovarian reserve producing a high number of embryos available for biopsy. Preimplantation genetic testing for aneuploidy does not improve ongoing pregnancy rates per cycle started when routinely applied on the general IVF population but seems to be a good tool of embryo selection for a selected category of patients with normal ovarian reserve, yet should be only practiced by experienced IVF clinics. If no euploid embryo is available after preimplantation genetic testing for aneuploidy, a low-level mosaic embryo can be considered and prioritized for transfer after appropriate genetic counseling.

The cost-effectiveness of preimplantation genetic testing for aneuploidy in the United States: an analysis of cost and birth outcomes from 158,665 in vitro fertilization cycles

BACKGROUND

A controversial and unresolved question in reproductive medicine is the utility of preimplantation genetic testing for aneuploidy as an adjunct to in vitro fertilization. Infertility is prevalent, but its treatment is notoriously expensive and typically not covered by insurance. Therefore, cost-effectiveness is critical to consider in this context.

OBJECTIVE

This study aimed to analyze the cost-effectiveness of preimplantation genetic testing for aneuploidy for the treatment of infertility in the United States.

STUDY DESIGN

As reported to the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System, a national data registry, in vitro fertilization cycles occurring between 2014 and 2016 in the United States were analyzed. A probabilistic decision tree was developed using empirical outputs to simulate the events and outcomes associated with in vitro fertilization with and without preimplantation genetic testing for aneuploidy. The treatment strategies were (1) in vitro fertilization with intended preimplantation genetic testing for aneuploidy and (2) in vitro fertilization with transfers of untested embryos. Patients progressed through the treatment model until they achieved a live birth or 12 months after ovarian stimulation. Clinical costs related to both treatment strategies were extracted from the literature and considered from both the patient and payer perspectives. Outcome metrics included incremental cost (measured in 2018 US dollars), live birth outcomes, incremental cost-effectiveness ratio, and incremental cost per live birth between treatment strategies.

RESULTS

The study population included 114,157 first fresh in vitro fertilization stimulations and 44,508 linked frozen embryo transfer cycles. Of the fresh stimulations, 16.2% intended preimplantation genetic testing for aneuploidy and 83.8% did not. In patients younger than 35 years old, preimplantation genetic testing for aneuploidy was associated with worse clinical outcomes and higher costs. At age 35 years and older, preimplantation genetic testing for aneuploidy led to more cumulative births but was associated with higher costs from both perspectives. From a patient perspective, the incremental cost per live birth favored the no preimplantation genetic testing for aneuploidy strategy from the <35 years age group to the 38 years age group and beginning at age 39 years favored preimplantation genetic testing for aneuploidy. From a payer perspective, the incremental cost per live birth favored preimplantation genetic testing for aneuploidy regardless of patient age.

CONCLUSION

The cost-effectiveness of preimplantation genetic testing for aneuploidy is dependent on patient age and perspective. From an economic perspective, routine preimplantation genetic testing for aneuploidy should not be universally adopted; however, it may be cost-effective in certain scenarios.

A major increase in oocyte cryopreservation cycles in the USA, Australia and New Zealand since 2010 is highlighted by younger women but a need for standardized data collection

STUDY QUESTION

What are the cohort trends of women undergoing oocyte cryopreservation (OC)?

SUMMARY ANSWER

There has been a dramatic increase in OC cycles undertaken each year since 2010, and the demographics of women accessing OC has shifted to a younger age group, but so far very few women have returned to use their cryopreserved oocytes in treatments.

WHAT IS KNOWN ALREADY

Although OC, as a method of fertility preservation, is offered around the world, global data are lacking on who is accessing OC, who is returning to thaw oocytes and whether these trends are changing.

STUDY DESIGN, SIZE, DURATION

A trinational retrospective cohort study was performed of 31 191 OC cycles and 972 oocyte thaw (OT) cycles undertaken in the USA (2010-2016) and 3673 OC and 517 OT cycles undertaken in Australia/New Zealand (Aus/NZ; 2010-2015).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Data were obtained from the USA Society for Assisted Reproductive Technology (SART) national registry and the Australian and New Zealand Assisted Reproduction Database (ANZARD). De-identified data were requested on all autologous oocyte freeze-all cycles and all cycles where autologous oocytes were thawed to be used in a treatment cycle for the time periods of interest.

MAIN RESULTS AND THE ROLE OF CHANCE

In both the USA and Aus/NZ, there has been a dramatic rise in the number of OC cycles performed each year (+880% in the USA from 2010 to 2016 and +311% in Aus/NZ from 2010 to 2015). Across both regions, most women undergoing OC were aged in their late 30s, but the average age decreased over time (USA: 36.7 years vs 34.7 years in 2010 and 2016, respectively). The number of women returning for thaw cycles was low (USA: 413 in 2016, Aus/NZ: 141 in 2015) and most thaw cycles (47%) across both regions involved oocytes that were frozen for <6 months. In the USA, a higher proportion of cycles resulted in a live birth when only thawed oocytes were used, compared to cycles that combined thawed oocytes with fresh oocytes (25% vs 11%, respectively; P < 0.001). Age at retrieval influenced live birth rate in the USA; 38% of thaw cycles started in women who stored oocytes when aged ≤35 years resulted in a live birth, whereas only 16% resulted in a live birth for women who stored oocytes when aged ≥36 years. Similar data were unobtainable from Aus/NZ.

LIMITATIONS, REASONS FOR CAUTION

There were limitations associated with both the SART and ANZARD data outputs received. The format in which the ANZARD data were provided, and the inconsistencies seen amongst cycle reporting in the SART dataset, restricted data interpretation. For example, both datasets did not provide a clear indication as to why women were undergoing OC and it was not possible to accurately calculate duration of storage for thaw cycles in the USA. We also did not obtain details on embryo quality from either database and acknowledge that embryo quality and subsequent outcome (embryo freezing or discard) would be of interest, especially when considering the efficacy of OC.

WIDER IMPLICATIONS OF THE FINDINGS

The data show that there is widespread demand for OC, and it is increasingly undertaken by younger women; however, the limitations encountered in the dataset support the need for a shift to a more uniform approach to data collection and presentation by large databases, worldwide.

STUDY FUNDING/COMPETING INTEREST(S)

This study received funding from the Fertility Society of Australia to support the ANZARD data extraction. M.J. is supported by an Australian Government Research Training Program Scholarship stipend. The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Definition, diagnostic and therapeutic options in recurrent implantation failure: an international survey of clinicians and embryologists

STUDY QUESTION

What is the global variability in recurrent implantation failure (RIF) definition, investigation and therapy, currently offered to patients undergoing IVF?

SUMAMRY ANSWER

Definitions, diagnostic investigations and treatments offered to RIF patients differ widely amongst assisted reproduction healthcare professionals and clinical guidelines on RIF are urgently needed.

WHAT IS KNOWN ALREADY

RIF affects around 10% of patients undergoing IVF worldwide. There is no consensus on the definition of RIF, its diagnostic investigations or the therapeutic options, which leads to inconsistencies in clinical practice.

STUDY DESIGN, SIZE, DURATION

A cross-sectional study of clinicians and embryologists was conducted between May and June 2020. The survey included 43 questions aimed at understanding participants' background and their current practice with regards to defining, investigating and managing RIF. The questions were designed by the European Society of Human Reproduction and Embryology (ESHRE) Special Interest Group (SIG) on implantation and early pregnancy following three consensus meetings.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 8579 ESHRE members from 6916 IVF centers were invited to participate using two global email calls based on their pre-specified interest in implantation and early pregnancy. SurveyMonkey and SPSS were used for data collection and analysis, respectively. Furthermore, differences were reported in the answers of European and non-European professionals, as well as between public and private settings and among clinicians clustered according to the average number of RIF patients treated per year.

MAIN RESULTS AND THE ROLE OF CHANCE

The final data set included 735 clinicians and 300 embryologist or IVF-biologists. The majority defines RIF based on the number of failed embryo transfers (ETs) with the most common threshold adopted being three ETs both fresh and frozen. More than two-thirds take lifestyle factors into account, mainly drugs, smoking and BMI. The highest consensus on which diagnostic investigations should be performed was reached for anatomical malformations and gynecological aspects focusing on hydrosalpinx, Asherman's syndrome, endometrial thickness and endometriosis. Concerning treatment of RIF patients, the highest consensus was reached for preconceptional therapies, including BMI adjustment, smoking and endometritis followed by therapies during IVF procedures.

LIMITATIONS, REASONS FOR CAUTION

The response rate was relatively low, but comparable to other surveys.

WIDER IMPLICATIONS OF THE FINDINGS

A consensus on definition, diagnosis and treatment of RIF would help to reduce costly, time-consuming and poorly validated approaches.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used. B.T. received support from Bayer for Clinical trials concerning endometriosis and Ferring for clinical trials concerning ovarian stimulation. She received reimbursement for travel expenses from Astropharm, Ferring. Dr Kade and is a shareholder of Reprognostics. She is a board member of the Austrian Society for Obstetrics and Gynecology (OEGGG), the associate head of the 'Reproduktionsmedizinische Zentren Baden-Württemberg' (RZBW), a member of guideline group of the German Society for Obstetrics and Gynecology (DGGG) and an editorial board member of the following journals: American Journal of Reproductive Immunology (AJRI), Archives of Gynecology and Obstetrics. All the other authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

International Committee for Monitoring Assisted Reproductive Technologies (ICMART): world report on assisted reproductive technologies, 2013

OBJECTIVE

To report the utilization, effectiveness, and safety of practices in assisted reproductive technology (ART) globally in 2013 and assess global trends over time.

DESIGN

Retrospective, cross-sectional survey on the utilization, effectiveness, and safety of ART procedures performed globally during 2013.

SETTING

Seventy-five countries and 2,639 ART clinics.

PATIENT(S)

Women and men undergoing ART procedures.

INTERVENTION(S)

All ART.

MAIN OUTCOME MEASURE(S)

The ART cycles and outcomes on country-by-country, regional, and global levels. Aggregate country data were processed and analyzed based on methods developed by the International Committee for Monitoring Assisted Reproductive Technology (ICMART).

RESULT(S)

A total of 1,858,500 ART cycles were conducted for the treatment year 2013 across 2,639 clinics in 75 participating countries with a global participation rate of 73.6%. Reported and estimated data suggest 1,160,474 embryo transfers (ETs) were performed resulting in >344,317 babies. From 2012 to 2013, the number of reported aspiration and frozen ET cycles increased by 3% and 16.4%, respectively. The proportion of women aged >40 years undergoing nondonor ART increased from 25.2% in 2012 to 26.3% in 2013. As a percentage of nondonor aspiration cycles, intracytoplasmic sperm injection (ICSI) was similar to results for 2012. The in vitro fertilization (IVF)/ICSI combined delivery rates per fresh aspiration and frozen ET cycles were 24.2% and 22.8%, respectively. In fresh nondonor cycles, single ET increased from 33.7% in 2012 to 36.5% in 2013, whereas the average number of transferred embryos was 1.81-again with wide country variation. The rate of twin deliveries after fresh nondonor transfers was 17.9%; the triplet rate was 0.7%. In frozen ET cycles performed in 2013, single ET was used in 57.6%, with an average of 1.49 embryos transferred and twin and triplet rates of 10.8% and 0.4%, respectively. The cumulative delivery rate per aspiration was 30.4%, similar to that in 2012. Perinatal mortality rate per 1,000 births was 22.2% after fresh IVF/ICSI and 16.8% after frozen ET. The data presented depended on the quality and completeness of the data submitted by individual countries. This report covers approximately two-thirds of world ART activity. Continued efforts to improve the quality and consistency of reporting ART data by registries are still needed.

CONCLUSION(S)

Reported ART cycles, effectiveness, and safety increased between 2012 and 2013 with adoption of a better method for estimating unreported cycles.

Multiple vitrification-warming and biopsy procedures on human embryos: clinical outcome and neonatal follow-up of children

STUDY QUESTION

Does double vitrification and warming of human blastocysts having undergone biopsy once or twice have an impact on the clinical outcome?

SUMMARY ANSWER

The clinical pregnancy rate obtained with double vitrification single biopsy blastocysts was comparable to that obtained with single vitrification single biopsy blastocysts in our center in the same time period (46%; 2016-2018), whereas that obtained with double-vitrified double-biopsied blastocysts seemed lower and will need further study.

WHAT IS KNOWN ALREADY

Genetic testing on cryopreserved unbiopsied embryos involves two cryopreservation procedures. Retesting of failed/inconclusive-diagnosed blastocysts inevitably involves a second round of biopsy and a second round of vitrification as well. To what extent this practice impacts on the developmental potential of blastocysts has been studied to a limited extent so far and holds controversy. Additionally, the obstetrical/perinatal outcome after the transfer of double-vitrified/single or double-biopsied blastocysts is poorly documented.

STUDY DESIGN, SIZE, DURATION

This retrospective observational study included 97 cycles of trophectoderm biopsy and preimplantation genetic testing (PGT) on vitrified-warmed embryos followed by a second round of vitrification between March 2015 and December 2019.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In 36 warming cycles, no biopsy was performed on the embryos before the first vitrification (single biopsy group). In 61 warming cycles, the embryos had been biopsied on Day 3 (n = 4) or on Day 5/6 (n = 57) before the first vitrification (double biopsy group). A second biopsy was mostly indicated in cycles of failed or inconclusive diagnosis at the first biopsy. Two cycles involved a more specific mutation test for X-linked diseases on male embryos and one cycle involved testing for a second monogenic indication supplementary to a previously tested reciprocal translocation. Post-warming suitability for biopsy, availability of genetically transferable embryos and clinical outcome of subsequent frozen-thawed embryo transfer (FET) cycles were reported. Neonatal follow-up of the children was included.

MAIN RESULTS AND THE ROLE OF CHANCE

In total, 91 cleavage-stage embryos and 154 blastocysts were warmed, of which 34 (37.4%) and 126 (81.8%), respectively, were of sufficient quality to undergo trophectoderm biopsy and were subsequently vitrified for a second time. Out of these, 92 underwent biopsy for the first time (single biopsy), whereas 68 underwent a second biopsy (double biopsy). After diagnosis, 77 blastocysts (48.1%) were revealed to be genetically transferable (44 in the single biopsy group and 33 in the double biopsy group). In 46 warming cycles, 51 blastocysts were warmed and 49 survived this second warming procedure (96.0%). Subsequently, there were 45 FET cycles resulting in 27 biochemical pregnancies and 18 clinical pregnancies with fetal heartbeat (40.0% per FET cycle: 44.0% in the single biopsy group and 35.0% in the double biopsy group, P = 0.54). Thirteen singletons were born (eight in the single biopsy group and five in the double biopsy group), while three pregnancies were ongoing. A total of 26 embryos (13 in each group) remain vitrified and have the potential to increase the final clinical pregnancy rate. The neonatal follow-up of the children born so far is reassuring.

LIMITATIONS, REASONS FOR CAUTION

This is a small retrospective cohort, thus, the implantation potential of double vitrification double biopsy blastocysts, as compared to double vitrification single biopsy blastocysts and standard PGT (single vitrification, single biopsy), certainly needs further investigation. Although one could speculate on birthweight being affected by the number of biopsies performed, the numbers in this study are too small to compare birthweight standard deviation scores in singletons born after single or double biopsy.

WIDER IMPLICATIONS OF THE FINDINGS

PGT on vitrified-warmed embryos, including a second vitrification-warming step, results in healthy live birth deliveries, for both single- and double-biopsied embryos. The neonatal follow-up of the 13 children born so far did not indicate any adverse effect. The present study is important in order to provide proper counseling to couples on their chance of a live birth per initial warming cycle planned and concerning the safety issue of rebiopsy and double vitrification.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

N/A.

Utilization of preimplantation genetic testing in the USA

PURPOSE

To evaluate the use of preimplantation genetic testing (PGT) and live birth rates (LBR) in the USA from 2014 to 2017 and to understand how PGT is being used at a clinic and state level.

METHODS

This study accessed SART data for 2014 to 2017 to determine LBR and the CDC for years 2016 and 2017 to identify PGT usage. Primary cycles included only the first embryo transfer within 1 year of an oocyte retrieval; subsequent cycles included transfers occurring after the first transfer or beyond 1 year of oocyte retrieval.

RESULTS

In the SART data, the number of primary PGT cycles showed a significant monotonic annual increase from 18,805 in 2014 to 54,442 in 2017 (P = 0.042) and subsequent PGT cycles in these years increased from 2946 to 14,361 (P = 0.01). There was a significant difference in primary PGT cycle use by age, where younger women had a greater percentage of PGT treatment cycles than older women. In both PGT and non-PGT cycles, the LBR per oocyte retrieval decreased significantly from 2014 to 2017 (P<0001) and younger women had a significantly higher LBR per oocyte retrieval compared to older women (P < 0.001). The CDC data revealed that in 2016, just 53 (11.4%) clinics used PGT for more than 50% of their cycles, which increased to 99 (21.4%) clinics in 2017 (P< 0.001).

CONCLUSIONS

A growing number of US clinics are offering PGT to their patients. These findings support re-evaluation of the application for PGT.

Specialist physicians' referral behavior regarding preimplantation genetic testing for single-gene disorders: Is there room to grow?

Objective

To assess whether primary care specialists’ demographics, specialty, and knowledge of preimplantation genetic testing for monogenic disorders (PGT-M) influence their practice patterns.

Design

Cross-sectional survey study.

Setting

Academic medical center.

Patient(s)

Not applicable.

Intervention(s)

None.

Main Outcome Measure(s)

Objective PGT-M knowledge, subjective comfort with PGT-related topics, PGT care practices (discussions/referrals), and PGT-M implementation barriers.

Result(s)

Our survey had 145 respondents: 65 obstetrician/gynecologists, 36 internists, and 44 pediatricians. Overall, 88% believed that patients at a risk of passing on genetic disorders should be provided PGT-M information. However, few discussed PGT-M with their patients (24%) or referred them for testing (23%). Over half (63%) believed that the lack of physician knowledge was a barrier to PGT use. In terms of subjective comfort with PGT, only 1 in 5 physicians felt familiar enough with the topic to answer patient questions. There were higher odds of discussing (odds ratio, 3.21; 95% confidence interval, 1.75–5.87) or referring for PGT (odds ratio, 2.52; 95% confidence interval, 1.41–4.51) for each additional 0.5 correct answers to PGT knowledge-related questions. The odds of referring patients for PGT-M were the highest among obstetrician/gynecologists compared with those among the internists and pediatricians.

Conclusion(s)

Physician specialty and PGT knowledge were associated with PGT-M care delivery practices. Although most specialists believed in equipping at-risk patients with PGT-M information, <1 in 4 discussed or referred patients for PGT. The low levels of PGT-related care among providers may be owed to inadequate knowledge of and comfort with the topic. An opportunity to promote greater understanding of PGT-M among primary care specialists exists and can in turn improve the use of referrals to PGT-M services.

Preimplantation Genetic Testing for Aneuploidy - a Castle Built on Sand

Preimplantation genetic testing for aneuploidy (PGT-A) has become a routine add-on for in vitro fertilization (IVF) to determine whether human embryos are to be clinically utilized or disposed of. Studies claiming IVF outcome improvements following PGT-A, however, used highly selected patient populations or inappropriate statistical methodologies. PGT-A was never clinically validated in its ability to define a human embryo as chromosomal normal, mosaic, or aneuploid, nor certified by a regulatory body, or an authoritative professional organization. Because of a high false-positive rate, PGT-A, actually reduces live IVF birth chances for many patients. Furthermore, in recent studies the PGT-A hypothesis was demonstrated to be mistaken for biological, mathematical and technical reasons. PGT-A, therefore, should clinically only be offered within experimental study frameworks.

Is Day-4 morula biopsy a feasible alternative for preimplantation genetic testing?

Objective

To assess the efficacy and clinical outcome of PGT-M undertaken on Day-3, Day-4 and Day-4 “delayed” embryos that were unsuitable for biopsy on Day-3.

Design and setting

Cohort-historical study of all consecutive patients admitted to the IVF-PGT-M program in a large tertiary center.

Main outcome measure(s)

The pregnancy rates and the percentages of complete, incomplete diagnosis, PCR failure, abnormal embryos in PGT of Day-3 cleavage-stage, Day-4 and Day-4 “delayed” embryos.

Patients and methods

We reviewed the medical files of all consecutive patients admitted to our IVF for a fresh IVF-PGT-M cycle. Patients were divided into 3 groups according to the day of blastomere biopsy: Day 3 cleavage-stage, Day-4 morula and Day-4 “delayed” embryos. The laboratory data, genetic diagnostic and clinical results were collected and compared between the different study groups.

Results

Nine hundred and six patients underwent PGT-M cycles in our PGT program: 747, 127 and 32 in the Day-3, Day- 4 and Day-4 “delayed” groups, respectively. Ongoing pregnancy rates per transfer and per patient (15.8% and 9.4%, respectively) were non-significantly lower in the Day-4 “delayed”, compared to Day-3 (21.4% and 17.5%, respectively) and Day-4 (24.3% and 19.7%, respectively). When comparing ALL morulas (Day-4 and Day-4 “delayed”) to ALL cleavage-stage embryos (Day-3, Day-4 and Day-4 “delayed”), a significantly higher ongoing pregnancy rate was demonstrated following the transfer of embryos derived from morula biopsy, as compared to biopsy at the cleavage-stage (33.3% vs 20.5%, p<0.03, respectively).

Conclusion

Day-4 embryo biopsy is feasible and yields comparable and even higher ongoing pregnancy rate if undertaken at the morula stage. Further studies evaluating the cumulative live-birth rate per started cycles in Day-3 vs Day-4 embryo biopsy for PGT-M are warranted.

Strategies to reduce multiple pregnancies during medically assisted reproduction

Multiple birth rates after fertility treatment are still high in many countries. Multiple births are associated with increased rates of preterm birth and low birth weight babies, in turn increasing the risk of severe morbidity for the children. The multiple birth rates vary in different countries between 2% and 3% and up to 30% in some settings. Elective single-embryo transfer, particularly in combination with frozen-embryo transfer and milder stimulation in ovulation induction/intrauterine insemination, to avoid multifollicular development is an effective strategy to decrease the multiple birth rates while still achieving acceptable live-birth rates. Although this procedure is used successfully in many countries, it ought to be implemented broadly to improve the health of the children. One at a time should be the normal routine.

Timing day-3 vitrification for PGT-M embryos: pre- or post-blastomere biopsy?

PURPOSE

To assess the efficacy and clinical outcomes of preimplantation genetic testing for monogenic diseases (PGT-M), following blastomere biopsy prior or following vitrification.

METHODS

A cohort-historical study of all consecutive patients admitted to IVF in a large tertiary center for PGT-M and PCR cycle from September 2016 to March 2020. Patients were divided into 4 groups: Group A1 consisted of patients undergoing day-3 embryos biopsy followed by a fresh transfer of unaffected embryos. Group A2 consisted of Group A1 patients that their surplus unaffected embryos were vitrified, thawed, and transferred in a subsequent FET cycle. Group B1 consisted of patients that their day-3 embryos were vitrified intact (without biopsy) for a subsequent FET cycle. Later embryos were thawed and underwent blastomere biopsies, and the unaffected embryos were transferred, while the surplus unaffected embryos were re-vitrified for a subsequent FET cycle. Group B2 consisted of Group B1 patients that their surplus unaffected embryos were re-vitrified, thawed, and transferred in a subsequent FET cycle. The laboratory data and clinical results were collected and compared between groups.

RESULTS

A total of 368 patients underwent 529 PGT-M cycles in our center: 347 with day-3 embryos biopsied before undergoing vitrification (Group A1) and 182 following vitrification and thawing (Group B1). There were no between group differences in embryo survival rate post-thawing, nor the ongoing implantation and pregnancy rates.

CONCLUSION

In PGT-M cycles, the timing of embryos vitrification, whether prior or following blastomere biopsy, has no detrimental effect on post-thawing embryo survival rate, nor their potential ongoing implantation and pregnancy rates.

Preimplantation Genetic Testing for Chromosomal Abnormalities: Aneuploidy, Mosaicism, and Structural Rearrangements

There is a high incidence of chromosomal abnormalities in early human embryos, whether they are generated by natural conception or by assisted reproductive technologies (ART). Cells with chromosomal copy number deviations or chromosome structural rearrangements can compromise the viability of embryos; much of the naturally low human fecundity as well as low success rates of ART can be ascribed to these cytogenetic defects. Chromosomal anomalies are also responsible for a large proportion of miscarriages and congenital disorders. There is therefore tremendous value in methods that identify embryos containing chromosomal abnormalities before intrauterine transfer to a patient being treated for infertility—the goal being the exclusion of affected embryos in order to improve clinical outcomes. This is the rationale behind preimplantation genetic testing for aneuploidy (PGT-A) and structural rearrangements (-SR). Contemporary methods are capable of much more than detecting whole chromosome abnormalities (e.g., monosomy/trisomy). Technical enhancements and increased resolution and sensitivity permit the identification of chromosomal mosaicism (embryos containing a mix of normal and abnormal cells), as well as the detection of sub-chromosomal abnormalities such as segmental deletions and duplications. Earlier approaches to screening for chromosomal abnormalities yielded a binary result of normal versus abnormal, but the new refinements in the system call for new categories, each with specific clinical outcomes and nuances for clinical management. This review intends to give an overview of PGT-A and -SR, emphasizing recent advances and areas of active development.