使用D3-6胚胎培養液分析胚胎染色體(niPGT-A) vs 傳統囊胚切片PGT

niPGT-A  DNA amplification failure 機率仍然偏高 約37%

傳統囊胚切片PGT DNA amplification failure 機率為0%

Noninvasive preimplantation genetic testing for aneuploidy exhibits high rates of deoxyribonucleic acid amplification failure and poor correlation with results obtained using trophectoderm biopsy

Deoxyribonucleic acid amplification failures are high among noninvasive preimplantation genetic testing samples and correlate poorly with trophectoderm biopsies and clinical outcomes. The clinical utility of this testing modality remains low.

Fertility and Sterility Published Mar 19, 2021  VOLUME 115, ISSUE 6, P1461-1470

Objective

To validate a commercially available noninvasive preimplantation genetic testing for aneuploidy (niPGT-A) assay by investigating the following: prevalence of deoxyribonucleic acid (DNA) amplification failure with niPGT-A; factors affecting amplification failure with niPGT-A; and frequency of discordant results between niPGT-A and traditional preimplantation genetic testing for aneuploidy.

Patient(s)

One hundred sixty-six blastocysts and their surrounding culture media from couples undergoing in vitro fertilization between July 2019 and May 2020 were analyzed.

Intervention(s)

Blastocyst-stage spent culture media samples underwent niPGT-A using a commercially available kit that used whole-genome amplification with a modified multiple annealing and looping-based amplification cycle protocol followed by next-generation sequencing. Preimplantation genetic testing for aneuploidy of trophectoderm (TE) biopsies was performed using targeted next-generation sequencing.

Main Outcome Measure(s)

The primary outcome was failure to achieve an interpretable result with niPGT-A. Factors affecting DNA amplification were also assessed. Discrepancies between niPGT-A and TE biopsy results were analyzed, and clinical outcomes were evaluated.

Result(s)

Deoxyribonucleic acid amplification failures with niPGT-A were observed in 37.3% (62/166) of the samples. With TE biopsy, no embryos exhibited DNA amplification failure. Embryos with a shorter duration of exposure to the culture media and no evidence of whole-chromosome aneuploidy on the TE biopsy displayed high rates of DNA amplification failure with niPGT-A. Of 104 embryos with both niPGT-A and TE biopsy results available, whole-chromosome discordance was noted in 42 cases (40.4%). Three embryos classified as aneuploid based on the niPGT-A result progressed to successful delivery.

Conclusion(s)

The rates of DNA amplification failure were high among the niPGT-A samples, virtually precluding the clinical applicability of niPGT-A in its current form.

本篇強調胚胎有相當自我修復染色體異常之能力

PGS顯示染色體異常之胚胎只能說有高比率之染色體異常  並無法100%斷定其異常

Plasticity of the human preimplantation embryo: developmental dogmas, variations on themes and self-correction

Human Reproduction Update, dmab016, https://doi.org/10.1093/humupd/dmab016

Published:

 

15 June 2021

BACKGROUND

IVF for the treatment of infertility offers unique opportunities to observe human preimplantation development. Progress in time-lapse technology (TLT) and preimplantation genetic testing (PGT) has greatly expanded our knowledge of developmental patterns leading to a healthy pregnancy or developmental failure. These technologies have also revealed unsuspected plastic properties of the preimplantation embryo, at macromolecular, cellular and multicellular levels.

OBJECTIVE AND RATIONALE

This review focuses on the emerging concept of plasticity of the human embryo as revealed by recent evidence derived from TLT and PGT, calling for an updated and more precise redefinition of the boundaries between normal and abnormal development.

SEARCH METHODS

PubMed was used to search the MEDLINE database for peer-reviewed English-language original articles and reviews concerning human preimplantation development. Cross-searches were performed by adopting ‘fertilisation‘, ‘pronucleus’, ‘cleavage’, ‘multinucleation’, ‘compaction’, ‘embryo’, ‘preimplantation genetic testing’, ‘aneuploidy’, mosaicism’, ‘micromanipulation’, ‘time-lapse microscopy’ and ‘IVF/assisted reproduction’ as main terms. The most relevant publications, i.e. those concerning major phenomena occurring during normal and abnormal development—with a focus on the human species—were assessed and discussed critically.

OUTCOMES

Advances in TLT and PGT have revealed an astonishing plasticity and self-correction ability of the human preimplantation embryo in vitro. At fertilisation, an abnormal number of pronuclei do not always result in the formation of an aneuploid blastocyst. Animal studies and preliminary human observations indicate that combining of parental genomes may occur at the early cleavage stage, if not at fertilisation. Multinucleation occurs with much higher prevalence than previously thought and may be corrected at later cleavage stages. Irregular cleavage (multichotomous, direct, rapid and reverse cleavages) can generate chromosome segregation abnormalities that often lead to developmental arrest, but that sporadically may be confined to cells excluded from the blastocyst, and may sometimes result in viable pregnancy. Mitotic errors can generate mosaic blastocysts, but alternatively normal embryos may form from selective death or clonal depletion of aneuploid cells.

男性高齡並不明顯提高胚胎染色體異常機率

Is there an association between paternal age and aneuploidy? Evidence from young donor oocyte-derived embryos: a systematic review and individual patient data meta-analysis 

Michal Dviri, Svetlana Madjunkova, Alex Koziarz, Mitko Madjunkov, Jordana Mashiach ...

Human Reproduction Update, Volume 27, Issue 3, May-June 2021, Pages 486–500, https://doi.org/10.1093/humupd/dmaa052

• Abstract 
  BACKGROUND

  Delayed parenthood, by both women and men, has become more common in developed countries. The adverse effect of advanced maternal age on embryo aneuploidy and reproductive outcomes is well known. However, whether there is an association between paternal age (PA) and embryonic chromosomal aberrations remains controversial. Oocyte donation (OD) is often utilized to minimize maternal age effects on oocyte and embryo aneuploidy, thus providing an optimal model to assess the effect of PA. Several studies have revealed a higher than expected rate of aneuploidy in embryos derived from young oocyte donors, which warrants examination as to whether this may be attributed to advanced PA (APA).

  OBJECTIVE AND RATIONALE

  The objective of this systematic review and individual patient data (IPD) meta-analysis is to evaluate existing evidence regarding an association between PA and chromosomal aberrations in an OD model.

  SEARCH METHODS

  This review was conducted according to PRISMA guidelines for systematic reviews and meta-analyses. Medline, Embase and Cochrane databases were searched from inception through March 2020 using the (MeSH) terms: chromosome aberrations, preimplantation genetic screening and IVF. Original research articles, reporting on the types and/or frequency of chromosomal aberrations in embryos derived from donor oocytes, including data regarding PA, were included. Studies reporting results of IVF cycles using only autologous oocytes were excluded. Quality appraisal of included studies was conducted independently by two reviewers using a modified Newcastle-Ottawa Assessment Scale. A one-stage IPD meta-analysis was performed to evaluate whether an association exists between PA and aneuploidy. Meta-analysis was performed using a generalized linear mixed model to account for clustering of embryos within patients and clustering of patients within studies.

  OUTCOMES

  The search identified 13 032 references, independently screened by 2 reviewers, yielding 6 studies encompassing a total of 2637 IVF-OD cycles (n = 20 024 embryos). Two ‘low’ quality studies using FISH to screen 12 chromosomes on Day 3 embryos (n = 649) reported higher total aneuploidy rates and specifically higher rates of trisomy 21, 18 and 13 in men ≥50 years. One ‘moderate’ and three ‘high’ quality studies, which used 24-chromosome screening, found no association between PA and aneuploidy in Day 5/6 embryos (n = 12 559). The IPD meta-analysis, which included three ‘high’ quality studies (n = 10 830 Day 5/6 embryos), found no significant effect of PA on the rate of aneuploidy (odds ratio (OR) 0.97 per decade of age, 95% CI 0.91–1.03), which was robust to sensitivity analyses. There was no association between PA and individual chromosome aneuploidy or segmental aberrations, including for chromosomes X and Y (OR 1.06 per decade of age, 95% CI 0.92–1.21). Monosomy was most frequent for chromosome 16 (217/10802, 2.01%, 95% CI 1.76–2.29%) and trisomy was also most frequent for chromosome 16 (194/10802, 1.80%, 95% CI 1.56–2.06%).

COH+OPU 使用GnRHantagonist  vs 黃體素防止LH上升 對於囊胚之染色體影響無差異 (正常染色體囊胚比率約 42 vs 39% )

Comparison of euploidy rates of blastocysts in women treated with progestins or GnRH antagonist to prevent the luteinizing hormone surge during ovarian stimulation 

Human Reproduction, Volume 35, Issue 6, June 2020, Pages 1325–1331,

STUDY QUESTION

Does the prevalence of euploid blastocysts differ between patients treated with progestin primed ovarian stimulation (PPOS) and those treated with conventional ovarian stimulation?

SUMMARY ANSWER

The numbers of blastocysts and euploid blastocysts per patient and the number of euploid embryos per injected oocyte are similar for patients undergoing progestin-primed ovarian stimulation and for those undergoing conventional ovarian stimulation with GnRH antagonist.

WHAT IS KNOWN ALREADY

New approaches to ovarian stimulation have been developed based on the use of drugs administrable by mouth instead of via injections. Attention has been dedicated to progestins to block the LH surge. Previous data regarding the number of oocytes retrieved and the number of good-quality embryos generated in PPOS have demonstrated similar outcomes when compared to conventional ovarian stimulation, even if some concerns regarding the quality of embryos have been advanced.

STUDY DESIGN, SIZE, DURATION

This is a prospective non-inferiority age-matched case–control study. In a period of 6 months, a total of 785 blastocysts from 1867 injected oocytes obtained from 192 patients were available for analysis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Infertile women undergoing IVF and preimplanation genetic testing (PGT) cycles were included. Forty-eight patients were treated with PPOS, and for each of them three age-matched historical controls (n = 144) treated with a GnRH antagonist protocol were selected. PGT was performed according to next-generation sequencing technology.

MAIN RESULTS AND THE ROLE OF CHANCE

Basal characteristics were similar in the two groups; a substantial similarity of the main outcome measures in the two treatment groups has also been found. The rate of formation of euploid blastocysts per oocyte was 21% in both the two treatment groups. The percentage of patients with euploid embryos and the total number of euploid blastocysts per patient (median and interquartile range, IQR) in the PPOS group were 38.7 (25.5–52.9) and 2 (1.3–3.1), respectively. These figures were not significantly different in women treated with the GnRH antagonist protocol i.e. 42 (28–53.8) and 2.1 (1.3–2.9), respectively.