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Born and Made
Are new reproductive and genetic technologies racing ahead of a society that is unable to establish limits to their use? Have the \"new genetics\" outpaced our ability to control their future applications? This book examines the case of preimplantation genetic diagnosis (PGD), the procedure used to prevent serious genetic disease by embryo selection, and the so-called \"designer baby\" method. Using detailed empirical evidence, the authors show that far from being a runaway technology, the regulation of PGD over the past fifteen years provides an example of precaution and restraint, as well as continual adaptation to changing social circumstances. Through interviews, media and policy analysis, and participant observation at two PGD centers in the United Kingdom,Born and Madeprovides an in-depth sociological examination of the competing moral obligations that define the experience of PGD.
Among the many novel findings of this pathbreaking ethnography of reproductive biomedicine is the prominence of uncertainty and ambivalence among PGD patients and professionals--a finding characteristic of the emerging \"biosociety,\" in which scientific progress is inherently paradoxical and contradictory. In contrast to much of the speculative futurology that defines this field,Born and Madeprovides a timely and revealing case study of the on-the-ground decision-making that shapes technological assistance to human heredity.
eBook
The 2019 PGDIS position statement on transfer of mosaic embryos within a context of new information on PGT-A
Background
A recently published Position Statement (PS) by the
Preimplantation Genetics Diagnosis International Society (PGDIS)
regarding utilization of preimplantation genetic testing for aneuploidy (PGT-A) in association with in vitro fertilization (IVF) contained inaccuracies and misrepresentations. Because opinions issued by the
PGDIS
have since 2016 determined worldwide IVF practice, corrections appear of importance.
Methods
The
International Do No Harm Group in IVF (IDNHG-IVF)
is a spontaneously coalesced body of international investigators, concerned with increasing utilization of add-ons to IVF. It is responsible for the presented consensus statement, which as a final document was reached after review of the pertinent literature and again revised after the recent publication of the STAR trial and related commentaries.
Results
In contrast to the PGDIA-PS
, we recommend restrictions to the increasing, and by IVF centers now often even mandated, utilization of PGT-A in IVF cycles. While PGT-A has been proposed as a tool for achieving enhanced singleton livebirth outcomes through embryo selection, continued false-positive rates and increasing evidence for embryonic self-correction downstream from the testing stage, has led
IDNHG-IVF
to conclude that currently available data are insufficient to impose overreaching recommendations for PGT-A utilization.
Discussion
Here presented consensus offers an alternative to the 2019
PGDIS
position statement regarding utilization of preimplantation genetic testing for aneuploidy (PGT-A) in association with in vitro fertilization (IVF). Mindful of what appears to offer best outcomes for patients, and in full consideration of patient autonomy, here presented opinion is based on best available evidence, with the goal of improving safety and efficacy of IVF and minimizing wastage of embryos with potential for healthy births.
Conclusions
As the
PGDIS
never suggested restrictions on clinical utilization of PGT-A in IVF, here presented rebuttal represents an act of self-regulation by parts of the IVF community in attempts to control increasing utilization of different unproven recent add-ons to IVF.
Journal Article
Preimplantation genetic testing in the current era, a review
Background
Preimplantation genetic testing (PGT), also referred to as preimplantation genetic diagnosis (PGD), is an advanced reproductive technology used during in vitro fertilization (IVF) cycles to identify genetic abnormalities in embryos prior to their implantation. PGT is used to screen embryos for chromosomal abnormalities, monogenic disorders, and structural rearrangements.
Development of PGT
Over the past few decades, PGT has undergone tremendous development, resulting in three primary forms: PGT-A, PGT-M, and PGT-SR. PGT-A is utilized for screening embryos for aneuploidies, PGT-M is used to detect disorders caused by a single gene, and PGT-SR is used to detect chromosomal abnormalities caused by structural rearrangements in the genome.
Purpose of Review
In this review, we thoroughly summarized and reviewed PGT and discussed its pros and cons down to the minutest aspects. Additionally, recent studies that highlight the advancements of PGT in the current era, including their future perspectives, were reviewed.
Conclusions
This comprehensive review aims to provide new insights into the understanding of techniques used in PGT, thereby contributing to the field of reproductive genetics.
Journal Article
Metabolic Profiles of Offspring Born From Biopsied Embryos from Toddlerhood to Preschool Age
Abstract
Context
Embryo biopsy, which is necessary for preimplantation genetic testing (PGT), has not been fully investigated regarding its potential influences and safety. Previous studies of children born from biopsied embryos (PGT children) have primarily centered around their growth and neuropsychological development, while there remains limited knowledge concerning their endocrine and metabolic parameters.
Objective
This study aims to examine the effect of trophectoderm (TE) biopsy on metabolic outcomes for PGT children.
Methods
A total of 1267 children from the Center for Reproductive Medicine, Shandong University, who were conceived through in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) with and without PGT, were analyzed in this study. Three sets of measurements pertaining to growth and metabolism were taken at each predetermined follow-up time point. The linear regression models within a generalized estimating equation were employed to examine the associations between the PGT and each outcome measure and the approach of false discovery rate was used to correct for multiple comparisons.
Results
After controlling for confounding factors and correcting for multiple comparisons, no statistically significant difference was identified in any of the measured variables between the PGT children and children conceived by IVF alone (IVF children) and children conceived through IVF using ICSI (ICSI children). The same is true also for age- or sex-based subgroup analyses.
Conclusion
Between the ages of 1 and 5 years, there are no clinically adverse metabolic outcomes observed in PGT children, and their metabolic profiles are essentially identical to those of IVF children and ICSI children.
Journal Article
Recurrent Implantation Failure-update overview on etiology, diagnosis, treatment and future directions
Recurrent implantation failure (RIF) refers to cases in which women have had three failed in vitro fertilization (IVF) attempts with good quality embryos. The definition should also take advanced maternal age and embryo stage into consideration. The failure of embryo implantation can be a consequence of uterine, male, or embryo factors, or the specific type of IVF protocol. These cases should be investigated to determine the most likely etiologies of the condition, as this is a complex problem with several variables. There are multiple risk factors for recurrent implantation failure including advanced maternal age, smoking status of both parents, elevated body mass index, and stress levels. Immunological factors such as cytokine levels and presence of specific autoantibodies should be examined, as well as any infectious organisms in the uterus leading to chronic endometritis. Uterine pathologies such as polyps and myomas as well as congenital anatomical anomalies should be ruled out. Sperm analysis, pre-implantation genetic screening and endometrial receptivity should be considered and evaluated, and IVF protocols should be tailored to specific patients or patient populations. Treatment approaches should be directed toward individual patient cases. In addition, we suggest considering a new initial step in approach to patients with RIF, individualized planned activities to activate the brain's reward system in attempt to improve immunological balance in the body.
Journal Article
Noninvasive preimplantation genetic testing for aneuploidy in spent medium may be more reliable than trophectoderm biopsy
Preimplantation genetic testing for aneuploidy (PGT-A) with trophectoderm (TE) biopsy is widely applied in in vitro fertilization (IVF) to identify aneuploid embryos. However, potential safety concerns regarding biopsy and restrictions to only those embryos suitable for biopsy pose limitations. In addition, embryo mosaicism gives rise to false positives and false negatives in PGT-A because the inner cell mass (ICM) cells, which give rise to the fetus, are not tested. Here, we report a critical examination of the efficacy of noninvasive preimplantation genetic testing for aneuploidy (niPGT-A) in the spent culture media of human blastocysts by analyzing the cell-free DNA, which reflects ploidy of both the TE and ICM. Fifty-two frozen donated blastocysts with TE biopsy results were thawed; each of their spent culture medium was collected after 24-h culture and analyzed by next-generation sequencing (NGS). niPGT-A and TE-biopsy PGT-A results were compared with the sequencing results of the corresponding embryos, which were taken as true results for aneuploidy reporting. With removal of all corona-cumulus cells, the false-negative rate (FNR) for niPGT-A was found to be zero. By applying an appropriate threshold for mosaicism, both the positive predictive value (PPV) and specificity for niPGT-A were much higher than TE-biopsy PGT-A. Furthermore, the concordance rates for both embryo ploidy and chromosome copy numbers were higher for niPGT-A than TE-biopsy PGT-A. These results suggest that niPGT-A is less prone to errors associated with embryo mosaicism and is more reliable than TE-biopsy PGT-A.
Journal Article
What is the clinical impact of the endometrial receptivity array in PGT-A and oocyte donation cycles?
PurposeTo evaluate the influence of the endometrial receptivity array (ERA) test on the implantation rate (IR) and pregnancy rate (PR) in patients with previous failed euploid embryo transfers (Euploid-ET) or oocyte donation embryo transfers (Donor-ET).MethodsSingle-center retrospective study of patients with ≥ 1 previous failed Euploi-ET (n = 24) or ≥ 2 failed Donor-ET (n = 32) who underwent an ERA test and a post-ERA Euploid-ET/Donor-ET between 2012 and 2018. Controls were patients with ≥ 1 previously failed Euploid-ET (n = 119) or ≥ 2 failed Donor-ET (n = 158) who underwent Euploid-ET/Donor-ET during the same period without performing an ERA test. Only blastocyst stage embryos were included. IR/PR was compared between the post-ERA ET and the last ET in the control group.ResultsThere was no statistically significant difference regarding IR [55.6% (34.6–76.5%) vs. 65.0% (56.9–73.1%)] nor PR (58.3% vs.70.6%, p = 0.238) in the Euploid-ET ERA vs. Euploid-ET control groups. In the Donor-ET arm, both IR [26.8% (12.3–41.4%) vs. 57.2% (50.1–64.3%)] and PR (34.4% vs. 65.2%, p = 0.001) were significantly lower in the ERA group. Multivariate analysis confirmed that performing an ERA test did not influence the PR in the Euploid-ET arm and was associated with a diminished PR in the Donor-ET arm. In the ERA group, 41.1% patients were non-receptive (NR). No significant difference was found regarding IR/PR in NR vs. receptive patients in both Euploid-ET/Donor-ET arms.ConclusionsIn our sample, the performance of an ERA test did not improve pregnancy outcomes. Future prospective studies in larger samples are needed to confirm the role of the ERA test in Euploid-ET/Donor-ET.
Journal Article
Preimplantation genetic testing for aneuploidy versus no genetic testing in couples undergoing intracytoplasmic sperm injection for severe male infertility: multicentre, open label, randomised controlled trial
AbstractObjectiveTo assess the efficacy of preimplantation genetic testing for aneuploidies (PGT-A) compared to intracytoplasmic sperm injection (ICSI) alone in couples undergoing ICSI treatment because of severe male infertility.DesignMulticentre, open label, randomised controlled trial.SettingFour reproductive medicine centres across China.Participants450 couples with severe male factor infertility scheduled for ICSI were randomly assigned (1:1) to undergo PGT-A or not (225 couples in each group).InterventionsICSI with genetic testing of blastocysts before transfer in the PGT-A group, and ICSI without genetic testing for the no PGT-A group.Main outcome measuresPrimary outcomes were live birth after the first embryo transfer and cumulative live birth (up to three transfer cycles) within 12 months after randomisation. Primary analysis was based on intention-to-treat principle.ResultsBetween 15 July 2018 and 6 January 2023, 450 of 1347 screened couples gave informed consent and were randomised to the intervention, ICSI with PGT-A (n=225), or ICSI with no additional genetic testing (n=225). In total, 109 couples in the PGT-A group (48.4%) and 104 couples in the no PGT-A group (46.2%) had a live birth after the first embryo transfer (odds ratio 1.09 (95% confidence interval (CI) 0.76 to 1.58), P=0.64). The cumulative live birth rates per woman were 60.4% (136/225) and 60.9% (137/225) in the PGT-A and no PGT-A groups, respectively (0.98 (0.67 to 1.43), P=0.92). The PGT-A group had significantly lower rates of pregnancy loss after the first embryo transfer (13 (5.8%) PGT-A group v 43 (19.1%) no PGT-A group, 0.26 (0.14 to 0.50), P<0.001) and cumulative pregnancy loss (25 (11.1%) v 51 (22.7%), 0.43 (0.25 to 0.72), P=0.001) than the no PGT-A group.ConclusionPGT-A did not improve live birth rates in ICSI for severe male infertility compared to ICSI alone, but reduced rates of pregnancy loss.Trial registrationClinicalTrials.gov NCT02941965.
Journal Article
Comparison of the euploidy rate in preimplantation genetic testing for aneuploidy cycles following progestin-primed versus gonadotropin-releasing hormone antagonist protocol: a randomized controlled study
Background
Progestins can block endogenous luteinizing hormone secretion from the pituitary gland and have shown similar efficacy in terms of collecting competent oocytes and embryos; however, some inconsistencies have been proposed by the previous papers regarding the quality of oocytes and embryos obtained with the use of progestins. This study aimed to compare the euploidy rate between women treated with progestin-primed ovarian stimulation (PPOS) and the gonadotropin-releasing hormone (GnRH) antagonist protocol.
Methods
This is a prospective randomized study of 240 infertile women undergoing PGT-A between August 2021 and July 2023. Infertile women with advanced maternal age (38–45 years), recurrent pregnancy loss (≥ 2 or 3 consecutive miscarriages), and repeated implantation failure (≥ 4 embryos replaced or ≥ 2 blastocysts replaced without success) undergoing PGT-A cycles were included. Women were randomly assigned into the PPOS group (
n
= 120) or the antagonist group (
n
= 120) according to a computer-generated randomization list. Dydrogesterone 20 mg per day was given from the start of ovarian stimulation until the trigger day in the PPOS group. In the antagonist group, an antagonist 0.25 mg was given daily from the sixth day of ovarian stimulation until the trigger day. The primary outcome measure was the euploidy rate, defined as the number of euploid blastocysts per injected oocyte.
Results
No significant differences were observed in the demographic and ovarian stimulation characteristics between the two groups. The euploidy rate was comparable between the PPOS and antagonist group (12.5% vs. 16.0% respectively,
P
> 0.05). No significant differences were observed between the two groups in positive pregnancy test, clinical pregnancy, miscarriage, ectopic pregnancy, or live birth rates per transfer in the first frozen embryo transfer cycles.
Conclusion
Both PPOS and antagonist protocols had similar euploidy rates in PGT-A cycles.
Trial registration
Clinicaltrials. gov identifier: NCT04989348 (
https://www.clinicaltrials.gov/
). Trial registration date: Clinicaltrials. gov: 30 July 2021.
Journal Article