The cleavage stage embryo

Prados, Fernando; Debrock, Sophie; Lemmen, Josephine G.; Agerholm, Inge

doi:10.1093/humrep/des224

Cited by 69 publications

(56 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…1). In particular, the complete exclusion of large fragments and blastomeres has been observed in both compact morulas and blastocysts from several mammalian species, including humans, rhesus macaques, cattle, and mice homozygous for the yellow allele (A y ) of the agouti locus (Calarco and Pedersen 1976; Lindner and Wright 1983; Alikani et al 1999, 2002; Hardy 1999; Van Soom et al 2003; Prados et al 2012; Chavez et al 2014). Although the frequency of blastomere exclusion is unknown since it is not a well-documented process, pre-implantation embryos are generally thought to tolerate the loss of one or more blastomeres based on blastomere biopsy for PGS.…”

Section: Aneuploidy Tolerance and Rescuementioning

confidence: 99%

Chromosomal instability in mammalian pre-implantation embryos: potential causes, detection methods, and clinical consequences

Daughtry

Chavez

2015

Cell Tissue Res

View full text Add to dashboard Cite

Formation of a totipotent blastocyst capable of implantation is one of the first major milestones in early mammalian embryogenesis, but less than half of in vitro fertilized embryos from most mammals will progress to this stage of development. Whole chromosomal abnormalities, or aneuploidy, are key determinants of whether human embryos will arrest or reach the blastocyst stage. Depending on the type of chromosomal abnormality, however, certain embryos still form blastocysts and may be morphologically indistinguishable from chromosomally normal embryos. Despite the implementation of pre-implantation genetic screening and other advanced in vitro fertilization (IVF) techniques, the identification of aneuploid embryos remains complicated by high rates of mosaicism, atypical cell division, cellular fragmentation, sub-chromosomal instability, and micro-/multi-nucleation. Moreover, several of these processes occur in vivo following natural human conception, suggesting that they are not simply a consequence of culture conditions. Recent technological achievements in genetic, epigenetic, chromosomal, and non-invasive imaging have provided additional embryo assessment approaches, particularly at the single-cell level, and clinical trials investigating their efficacy are continuing to emerge. In this review, we summarize the potential mechanisms by which aneuploidy may arise, the various detection methods, and the technical advances (such as time-lapse imaging, “-omic” profiling, and next-generation sequencing) that have assisted in obtaining this data. We also discuss the possibility of aneuploidy resolution in embryos via various corrective mechanisms, including multi-polar divisions, fragment resorption, endoreduplication, and blastomere exclusion, and conclude by examining the potential implications of these findings for IVF success and human fecundity.

show abstract

Section: Aneuploidy Tolerance and Rescuementioning

confidence: 99%

Chromosomal instability in mammalian pre-implantation embryos: potential causes, detection methods, and clinical consequences

Daughtry

Chavez

2015

Cell Tissue Res

View full text Add to dashboard Cite

show abstract

“…Generally, embryo assessment is limited to static microscopic evaluations [17][18][19]. Alternative selection methods include genetic screening [20][21][22], morphokinetics [23], metabolomics [24,25], proteomics, oxygen consumption measurement and birefringence imaging [26].…”

Section: Introductionmentioning

confidence: 99%

Developmental capacity and pregnancy rate of tetrahedral- versus non-tetrahedral-shaped 4-cell stage human embryos

Cauffman

Verheyen

Tournaye

2014

J Assist Reprod Genet

View full text Add to dashboard Cite

Purpose The arrangement of the blastomeres within the 4-cell stage embryo reflects the orientation of the cleavage planes during the second division. To examine their relevance, the developmental capacity and the pregnancy rate were compared between tetrahedral-shaped and non-tetrahedralshaped 4-cell stage human embryos. Methods The study included 3,546 4-cell stage embryos. The arrangement of the blastomeres at the 4-cell stage was annotated as being tetrahedral or non-tetrahedral on day 2 of preimplantation development. Embryo quality was compared on day 3 and day 5. Pregnancy rates were calculated per single embryo transfer on day 3 or day 5. Results In total, 2,803 4-cell stage embryos (79 %) displayed a tetrahedral arrangement and 743 (21 %) displayed a non-tetrahedral arrangement. Tetrahedralshaped embryos developed more into high-quality embryos on day 3 (p<0.001) and day 5 (p=0.036) and had a higher blastulation rate (p=0.009). Though, the number of high-quality embryos selected for transfer did not differ between both groups on day 3 (p=0.167) and day 5 (p~1). Three hundred thirty single embryo transfers were analysed. No significant difference in clinical pregnancy was found between both groups after transfer on day 3 (p=0.209) and day 5 (p=0.653). Conclusions The arrangement of the blastomeres according to their previous cleavage planes was correlated to the developmental potential of the 4-cell stage embryo up to the blastocyst stage. If embryo transfers are performed on day 3 and day 5 of development using embryos of adequate quality, the blastomere arrangement at the 4-cell stage had no predictable value regarding pregnancy success.

show abstract

“…Furthermore, we analyzed the correlation between sperm chromatin status in patients' ejaculates, i.e., maturity and integrity, and the two parameters of zygote development, i.e., embryo development defined as the percentage of oocyte that can develop into a zygote within 72 hours compared to the total sperm-injected oocyte and the cleavage rate defined as the percentage of zygotes divided into more than 8 blastomeres within 72 hours [Prados et al 2012]. The analysis of the overall samples showed that there was no significant correlation between sperm chromatin maturity and either embryo formation (p=0.415) or cleavage rate (p=0.282).…”

Section: Resultsmentioning

confidence: 99%

Sperm chromatin maturity and integrity correlated to zygote development in ICSI program

Asmarinah

Syauqy

Umar

et al. 2016

Systems Biology in Reproductive Medicine

View full text Add to dashboard Cite

This study aimed to evaluate sperm chromatin maturity and integrity of that injected into goodquality oocytes in an in vitro fertilization-intra cytoplasmic sperm injection (IVF-ICSI) program. A cut-off value of sperm chromatin maturity and integrity was developed as a function of their correlation to the zygote development, i.e., embryo formation and cleavage rate. The study assessed sperm chromatin maturity using aniline blue (AB) staining, whereas toluidine blue (TB) staining was used to assess sperm chromatin integrity. Ejaculates from 59 patients undergoing ICSI and 46 fertile normozoospermic donors for determination of normal values of sperm chromatin status were used in this study. Embryo formation and cleavage rates were observed for the period of 3 days after ICSI. There was a significant difference in the percentage of sperm with mature chromatin between ejaculate from ICSI patients and fertile donor (p=0.020); while there was no significant difference in sperm chromatin integrity of both samples (p=0.120). There was no significant correlation between sperm chromatin maturity and either embryo formation or cleavage rate; as well as sperm chromatin integrity to both parameters of zygote development (p>0.05). Furthermore, we found that the cut-off value of sperm chromatin maturity and integrity of the fertile normozoospermic ejaculates were 87.2% and 80.2%, respectively. Using the cut-offs, we found that low sperm chromatin maturity at the level of <87% correlated significantly with the cleavage rate of the zygote (p=0.022; r=0.371); whereas poor sperm chromatin integrity at the level of <80% correlated with embryo formation (p=0.048; r=0,485). In conclusion, this study showed that poor maturity and integrity of sperm chromatin (AB<87% and TB<80%, respectively), could affect zygote development following ICSI.

show abstract

The cleavage stage embryo

Cited by 69 publications

References 63 publications

Chromosomal instability in mammalian pre-implantation embryos: potential causes, detection methods, and clinical consequences

Chromosomal instability in mammalian pre-implantation embryos: potential causes, detection methods, and clinical consequences

Developmental capacity and pregnancy rate of tetrahedral- versus non-tetrahedral-shaped 4-cell stage human embryos

Sperm chromatin maturity and integrity correlated to zygote development in ICSI program

Contact Info

Product

Resources

About