P–148 Effect of additional laser assisted drilling (LAD) during trophectoderm (TE) biopsy on mosaicism rate

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Z Q Tee ◽  
C W Chan ◽  
A Y X Lim ◽  
C S S Lee
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Pulse Length ◽  
Oocyte Retrieval ◽  
Assisted Hatching ◽  
Biopsy Site ◽  
Extra Step ◽  
Registration Number ◽  
Group A ◽  
The Mean

Abstract Study question Does applying additional LAD during TE biopsy cause higher mosaicism rate in blastocysts? Summary answer Applying LAD during TE biopsy to create additional zona opening will produce more mosaic blastocysts. What is known already In Alpha IVF, laser assisted hatching (LAH) was done on day3 after ICSI for all pre-implantation genetic testing for aneuploidy (PGT-A) cycles. TE biopsy techniques used were laser+pulling (L+P), laser+flicking (L+F) and flicking only (F). At the time of biopsy, an extra step of creating additinonal artificial opening by LAD may be required when (a) blastocyst has very little herniated cells; (b) inner cell mass (ICM) is at the hatching point or biopsy site. Our internal study showed that biopsy using different techniques (L+P, L+F and F) does not affect mosaicism rate. Study design, size, duration This prospective study was designed to evaluate the effect of additional LAD during TE biopsy on the mosaicism rate. This study was conducted between 11th March–19th August 2019. Four hundred forty-three (443) patients had undergone oocyte retrieval and blastocyst culture after intracytoplasmic injection (ICSI) was done. A total of 824 hatching blastocyst (BG5) and fully hatched blastocyst (BG6) with at least a Grade A or Grade B TE (Gardner’s grading) were included in this study. Participants/materials, setting, methods LAH was done on day3 post-ICSI while biopsy was done on day5 and/or day6 for PGT-A. Laser pulse length used during LAH and biopsy was fixed at 400ms. The biopsied blastocysts were classified into 3 groups: (A) BG6 (n = 79), (B) BG5 without additional LAD during biopsy (n = 713) and (C) BG5 with additional LAD (n = 32). The number of biopsied cells ranged from 5–10 cells. Biopsied cells were tested using Next Generation Sequencing (Ion Torrent, USA). Main results and the role of chance The mosaicism rates for Group A, B and C were 19.0% (15/79), 23.4% (167/713) and 39.5% (15/38) respectively. Mosaicism rates of Group A and B were comparable (p = 0.4807), whilst Group C had significant higher mosaicism rate compared to Group A and B (p = 0.0238 and p = 0.0319 respectively). The mean age of Group A, B and C were 31.1, 31.4 and 27.1 respectively. The mean age between these 3 groups were not statistically significant (A vs B, p = 0.0713; A vs C, p = 0.06727; and B vs C, p = 0.4408). Limitations, reasons for caution Additional LAD during TE biopsy maybe be a confounding variable which affects the mosaicism rate. Moreover, the increase in mosaicism rate could be due to other unknown factors. A larger sample size is needed to confirm the results. Wider implications of the findings: Based on our study, additional LAD during TE biopsy is not recommended as this may increase mosaicism rate. Biopsy should be done when the blastocyst has more herniated cell or when the ICM leaves the hatching point/biopsy site. Trial registration number Not applicable

P–158 Assisted Hatching on D + 3 in order to facilitate trophectoderm biopsy in blastocyst for PGT-A is not advisable in all patients

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
P Belchin ◽  
Y Cabello ◽  
M Sanche. d. Burgos ◽  
J Guerrero ◽  
M D Riva ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Time Lapse ◽  
Fertilization Rate ◽  
Blastocyst Stage ◽  
Assisted Hatching ◽  
Culture Dish ◽  
Key Factor ◽  
Registration Number ◽  
Number Of Cycles

Abstract Study question Is it useful or beneficial to perform Assisted Hatching (AH) on D + 3 previously to biopsy for PGT-A on blastocyst stage on D + 5? Summary answer The routine use of AH on D + 3 to facilitate the embryo biopsy on D + 5 could negatively influence the development of the embryos to blastocyst stage. What is known already The blastocyst stage is the optimal stage for performing biopsies for PGT-A, which has been reported as a key factor determining the growing clinical application of this strategy worldwide. For trophectoderm (TE) biopsy, laser-assisted drilling is used to create a zona opening on D + 3 or D + 5 of development. The method of zona opening on D + 3 allows some of the TE cells to herniate during blastocyst formation and expansion, which facilitates the biopsy process. However, this method may result in herniation of inner cell mass cells instead of TE or maybe could affect the development of the embryo to blastocyst stage. Study design, size, duration A total of 100 PGT-A cycles were performed in 2019 and 2020. In 78 of them laser-assisted drilling was used to create a zona opening on D + 5 only in those embryos which arrived to blastocyst stage for TE biopsy (Group No-AH). In 22 cycles the same drilling was achieved on D + 3 in all embryos, independently of their quality (Group AH). The average of embryos per cycle in each group was 5 and 4.3 respectively. Participants/materials, setting, methods A total of 100 PGT-A cycles coming from 65 patients were studied. The average of the age of the patients was 40.83 (SD 3.45) in the group No-AH vs 42.18 (SD 3.42) in the Group AH (p = 0.108), so the age was not a determining factor for the development of the embryos. We analyzed by χ 2 test differences between groups on fertilization rates, number of embryos, development to blastocyst stage, euploidy and pregnancy rates. Main results and the role of chance The fertilization rate was 74.79% (No-AH group) and 68.53% (AH group) with no significative statistical differences (p = 0.12). In the No-AH group, the TE biopsy was performed on D + 5 in 63 cycles (81%). In the AH group, 41% of cycles didn’t reach the blastocyst stage, obtaining statistical differences between groups (p = 0.035). We found also significant differences in the number of cycles with biopsied blastocyst when we had 1 to 6 embryos/cycle on D + 3 between groups (p = 0.002), without obtaining any blastocyst to be diagnosed in 53% of the cycles in AH group vs 27% in No-AH group. When the number of embryos on D + 3 per cycle was > 6, at least 1 embryo reached the blastocyst stage in both groups, although this number was higher in No-AH group. The rate of biopsied blastocysts was significantly higher in the No-AH group compared to the AH group (46.61 vs 34.69) with a p = 0.031. The rate of euploid embryos analyzed was 23.30% in the No-AH group compared to 29.41% in the AH group, although no significant differences were found (p = 0.44) between groups. In the No-AH group, a clinical pregnancy rate of 52.94% was obtained (n = 34) vs 50% in the AH group (n = 4) (p = 0.91). Limitations, reasons for caution We have recently started to perform AH on D + 3, so the number of cases is smaller than No-AH group. We use a time lapse incubator in all cases, so in the No-AH the culture dish is changed, disturbing the stable incubation environment, while in the other group it is not. Wider implications of the findings: The use of AH on D + 3 in order to facilitate the TE biopsy on D + 5 could affect negatively the development of the embryos to blastocyst stage. Its routine use should be avoided based on laboratory workload, mainly if the patient has less than 7 embryos at D + 3. Trial registration number Not applicable

P–516 Evidence for self-correction in preimplantation embryos by comparative molecular karyotyping of blastocoele fluid, trophectoderm and inner cell mass

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
D Zhigalina ◽  
N Skryabin ◽  
O Kanbekova ◽  
V Artyukhova ◽  
A Svetlakov ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Morphological Characteristics ◽  
Preimplantation Embryos ◽  
Molecular Karyotyping ◽  
Embryonic Cells ◽  
Developmental Potential ◽  
Positive Correlation ◽  
Registration Number ◽  
Molecular Karyotype

Abstract Study question Does the molecular karyotype of the cell-free DNA (cfDNA) from the blastocyst fluid (BF) can predict the efficiency of self-correction of karyotype of preimplantation embryo? Summary answer Detection of aneuploidies in the BF potentially can point out on effective self-correction of blastocyst karyotype and consequently on high developmental potential of mosaic embryos. What is known already Correction of aneuploidies in the preimplantation embryos can be provided by several mechanisms, including apoptosis. The predominant death of aneuploid cells was demonstrated in mouse embryos (Bolton, 2016). A positive correlation was also shown between the concentration of cfDNA from the BF of human blastocyst and the morphology of the embryo, as well as between the activity of caspase–3 and the concentration of cfDNA (Rule, 2018). The incidence of failed amplification after WGA being significantly higher among euploid blastocysts (Magli, 2019). The capacity of abnormal cells extruding into the BF would be related to the embryo development potential (Gianaroli, 2019). Study design, size, duration This is a prospective observational study of thirty-one Day 5 human blastocysts. Cryopreserved blastocysts were received after treatment cycles at the IVF Center with informed consent obtained from couples. The average age of 15 women was 32.25±5 years. The morphological characteristics of blastocysts were estimated in accordance with the Gardner classification (Gardner, Schoolcraft, 1999). The procedure of BF aspiration and trophectoderm (TE) and ICM cells separation of the blastocysts was previously described (Tsuiko, 2018). Participants/materials, setting, methods WGA was performed by PicoPLEX kit (Rubicon Genomics, USA) or REPLI-g Mini kit (Qiagen) according to manufacturer’s protocols. The DNA of the BF, ICM and TE were analyzed separately using cCGH, aCGH and NGS. SurePrint G3 Human CGH Microarrays (8x60K, Agilent Technologies) were used according to the manufacturer’s recommendations. Image analysis was done using ISIS (v.5.5) (Metasystems) and Agilent CytoGenomics Software (v.3). VeriSeq™ PGS Kit - MiSeq® System (Illumina) was used for NGS. Main results and the role of chance Molecular karyotypes of all three samples - BF, ICM and TE, were obtained for 23 (74.2%) blastocysts. A correlation between the woman’s age and the number of aneuploidies in cfDNA (p = 0.0009) was found. A positive correlation may indicate that the number of aneuploidies in the embryonic cells increases with the age of a woman, however, the embryonic karyotype undergoes self-correcting through the elimination of aneuploid cells. It was noted that well-developing blastocysts (groups 4–5, according to Gardner’s classification) had fewer aneuploidies in ICM (p = 0.0141) and TE (p = 0.0436). In contrast, there was a tendency to an increase in the number of aneuploidies in the BF during blastocysts transition from stage 3 to 5 (p = 0.3542). We assessed the relationship between the number of aneuploidies in groups of blastocysts with different characteristics of ICM (groups “A” and “B” according to Gardner’s classification). These groups significantly differ in the number of aneuploidies in cfDNA (p = 0.0352), although the statistically significant differences between the number of aneuploidies in ICM (p = 0.5992) and in TE (p = 0.5934) was not detected. Thus, higher-quality embryos in terms of ICM morphology contain more abnormalities in the BF, since in this group the elimination of aneuploid cells is more efficient. Limitations, reasons for caution The number of embryos is limited in this study. More comprehensive studies are required to confirm the observed tendency. Wider implications of the findings: Aneuploid cells elimination can be a cause of increasing cfDNA concentration in the BF, which may be a marker of the viability of mosaic embryos when it is necessary to decide on mosaic embryo transfer. This study was supported by the RFBR (15–04–08265) and by the RSF (20–74–00064). Trial registration number Not applicable

scholarly journals Factors associated with subchorionic hematoma formation in pregnancies achieved via assisted reproductive technologies

2020 ◽  
Vol 37 (2) ◽  
pp. 305-309
Author(s):  
Brady T. West ◽  
Parviz K. Kavoussi ◽  
Kate C. Odenwald ◽  
Krista London ◽  
Caitlin L. Hunn ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Assisted Reproductive Technologies ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Reproductive Technologies ◽  
Assisted Hatching ◽  
Factors Associated ◽  
Uterine Surgery ◽  
Multivariable Logistic Regression ◽  
Significant Difference

Abstract Purpose To determine if certain clinical and/or embryologic factors are independently associated with the increased prevalence of subchorionic hematoma (SCH) among pregnancies achieved via in vitro fertilization (IVF) with fresh embryo transfer (ET). Design Retrospective chart review. Methods In this retrospective study, data were abstracted from 210 autologous oocyte IVF clinical pregnancies that resulted from fresh ET at a single fertility center from January 2012 through December 2016. Clinical and embryology laboratory variables were analyzed as possible factors associated with the presence or absence of SCH in IVF pregnancies via bivariate associations and multivariable logistic regression analyses. Independent variables included prior uterine surgery versus no uterine surgery, peak estradiol, and progesterone levels, day 3 (n = 92) versus day 5 (n = 118) ET, and assisted hatching versus no assisted hatching. Among the day 5 ET subgroup of 118 patients, 117 had data for the variables inner cell mass (ICM) grading and trophectoderm (TE) because one day 5 ET was at the morula stage. Results We found a significant bivariate association between TE grading and SCH, where cases with TE grade “A” were significantly less likely to have SCH compared with cases with grades “B” or “C.” This significant difference remained when adjusting for the other factors considered in a multivariable logistic regression model for the probability of SCH. Conclusions The data analyzed here suggest that a less-advanced trophectoderm grade may be a potential factor that is associated with the presence of SCH in pregnancies achieved via IVF.

92 EFFECTS OF ZONA PELLUCIDA CUTTING BY LASER ON THE CRYOSURVIVAL AND HATCHING RATES OF VITRIFIED BLASTOCYSTS IN BUFFALO (BUBALUS BULALIS)

2014 ◽  
Vol 26 (1) ◽  
pp. 160
Author(s):  
C. Yang ◽  
J. Shang ◽  
H. Zheng ◽  
F. Huang ◽  
X. Liang ◽  
...  
Keyword(s):  
Zona Pellucida ◽  
Natural Science ◽  
Cell Mass ◽  
Pulse Length ◽  
Assisted Hatching ◽  
Hatching Rate ◽  
Group 3 ◽  
Group 2 ◽  
Group 1 ◽  
Hatching Rates

The objective of this study was to determine if zona pellucida (ZP) opening before cryopreservation or after thawing would effect cryosurvivability and hatching rate of vitrified blastocysts produced by IVF. The IVF blastocysts were derived from oocytes obtained from abattoir ovaries; 15–20 μm ZP opening by a XYClone® system (Hamilton Thorne Biosciences, Beverly, MA, USA), using a pulse strength of 90% and pulse length of 800 μs, was adopted for assisted hatching. The hatching rates of fresh blastocysts of various ages with or without ZP opening were observed within 24 h. Furthermore, 20% ethylene glycol (EG) + 20% dimethyl sulfoxide (DMSO) + 0.5 M sucrose was adopted as vitrificaiton medium in the following experiments, and the expanded blastocysts harvested on Days 6, 7, 8, and 9 were respectively divided into three groups: Group 1: the blastocysts were vitrified after 15 to 20 μm ZP opening opposite to the inner cell mass, and the blastocoels were also blotted in order to outflow the blastocoelic fluid before vitrification; Group 2: the 15 to 20 μm ZP cutting by laser was performed immediately after thawing; Group 3: as control, the blastocysts were vitrified and thawed without any other treatment. The thawed blastocysts in different groups were cultured for 72 h to observe the survival and hatching rates. The results showed that 1) the hatching rate of fresh Day 9 blastocysts that underwent ZP cutting was higher than that of fresh counterpart (77.8% v. 50.0%, 28/36 v. 20/40, P < 0.05); 2) after vitrification, the ZP of blastocysts was averagely thickened for 2.8 μm; and 3) the cryosurvival and hatching rates of Days 6 to 8 blastocysts in three groups were not different from each other, whereas as for Day 9 blastocysts, the cryosurvival rate of vitrified blastocysts in Group 1 was significantly higher than Group 3 (75.0% v. 53.8%, 30/40 v. 28/52, P < 0.05), and the hatching rate of vitrified blastocysts in Group 2 was significantly higher than Group 3 (80.0% v. 42.9%, 16/20 v. 12/28, P < 0.05). In conclusion, laser-assisted hatching can promote the hatching rate of fresh and vitrified blastocysts derived from Day 9. Furthermore, ZP opening and blastocoel breaking before vitrification can also improve the cryosurvival rate of Day 9 blastocysts. This research was supported by grants from the National Natural Science Foundation of China (31160456) and the Natural Science Foundations of China under Grant No. 0991011 and No. 2011GXSFB018045)

scholarly journals Apoptotic cells in mouse blastocysts are eliminated by neighbouring blastomeres

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jozef Pisko ◽  
Alexandra Špirková ◽  
Štefan Čikoš ◽  
Lucia Olexiková ◽  
Veronika Kovaříková ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Low Frequency ◽  
Microscopic Analysis ◽  
Annexin V ◽  
Gene Transcript ◽  
Apoptotic Cells ◽  
Embryonic Cells ◽  
Fluorescence Staining ◽  
The Mean

AbstractApoptosis is a physiological process that occurs commonly during the development of the preimplantation embryo. The present work examines the ability of apoptotic embryonic cells to express a signal promoting their phagocytosis, and quantifies the ability of neighbouring, normal embryonic cells to perform that task. Microscopic analysis of mouse blastocysts revealed phosphatidylserine externalization to be 10 times less common than incidence of apoptotic cells (as detected by TUNEL). In spite of the low frequency of phosphatidylserine-flipping (in inner cell mass, no annexin V staining was recorded), fluorescence staining of the plasma membrane showed more than 20% of apoptotic cells to have been engulfed by neighbouring blastomeres. The mean frequency of apoptotic cells escaping phagocytosis by their extrusion into blastocyst cavities did not exceed 10%. Immunochemically visualised RAC1 (an enzyme important in actin cytoskeleton rearrangement) was seen in phagosome-like structures containing a nucleus with a condensed morphology. Gene transcript analysis showed that the embryonic cells expressed 12 receptors likely involved in phagocytic process (Scarf1, Msr1, Cd36, Itgav, Itgb3, Cd14, Scarb1, Cd44, Stab1, Adgrb1, Cd300lf, Cd93). In conclusion, embryonic cells possess all the necessary mechanisms for recognising, engulfing and digesting apoptotic cells, ensuring the clearance of most dying blastomeres.

scholarly journals 165RE-EXPANSION AND QUALITY OF SPLIT BOVINE EMBRYOS IN VITRO

2004 ◽  
Vol 16 (2) ◽  
pp. 205 ◽  
Author(s):  
P. Kesseler ◽  
E. Mahabir ◽  
M. Köster ◽  
M. Gilles ◽  
K. Wimmers ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Cell Counting ◽  
Bovine Embryos ◽  
Becton Dickinson ◽  
Group A ◽  
Group B ◽  
Number Of Cells

Transferring split bovine embryos results in a higher number of calves born per embryo. In addition to generating genetically identical progeny, biopsies can be made for molecular biological analyses. We aimed to determine the effect of splitting ratio on the in vitro development of Day 7 (164 to 168h post insemination) IVP bovine embryos. The inner cell mass (ICM) and trophoblast cells were split in three ratios (50:50, 60:40 and 70:30) with a Beaver microblade (Becton Dickinson, N.J., USA.) fixed to a micromanipulator under an inverse microscope at 100 X (Leica, Bensheim, Germany). Split blastocysts were cultured singly in 50μL drops of CR1aa medium at 39°C under 5% CO2 in a moisture-saturated atmosphere. After 1 and 2h culture, the morphology was assessed by judging the shape of the embryos and re-development of the blastocoel. On Day 8 (after 22h culture), the shape of the blastocysts, development of the ICM, blastocoel, proportion of degenerated cells and embryos and re-expanded blastocysts were recorded. Embryos were stained with propidium iodide and Hoechst 33258 for cell counting. The re-expansion status of Group A (50, 60 and 70%) and B (50, 40 and 30%) embryos after 1 and 2h and their quality after 22h culture (1: excellent=&lt;10% degenerated cells, well-defined ICM; 2: fair=&lt;20% degenerated cells) are shown in Table 1. With regards to Group A split blastocysts, a higher (P&lt;0.05) percentage of embryos that re-expanded after 1 and 2h and which yielded Quality 1 and 2 embryos suitable for embryo transfer was observed with the 60% and 70% than with demi-embryos. There were significant differences (P&lt;0.05) between all split blastocysts in Group B after 1h culture. The 30% split embryos showed the lowest re-expansion rate and quality of embryos after 2h and 22h culture, respectively. No differences (P&lt;0.05) were seen in the ratio of the ICM to the total number of cells in both Group A and B. This study showed that the ratio in which blastocysts were split had a significant effect on re-expansion and quality but not on the number of cells. Table 1

221 HOXB9 IS DIFFERENTIALLY EXPRESSED IN THE TWO FIRST CELL LINES OF THE MAMMALIAN EMBRYO

2015 ◽  
Vol 27 (1) ◽  
pp. 200
Author(s):  
C. Sauvegarde ◽  
R. Rezsöhazy ◽  
I. Donnay
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Blastocyst Stage ◽  
Nuclear Staining ◽  
Mammalian Embryo ◽  
Mean Intensity ◽  
Whitney Test ◽  
Mann Whitney Test ◽  
The Mean

Hox proteins are transcription factors known to be essential for embryo patterning. The detection of some Hox transcripts in oocytes and early embryos suggests that they could play a role before gastrulation. We previously demonstrated Hoxb9 expression in oocytes and from the zygote to the blastocyst stage in the mouse and the bovine (Paul et al. 2011 Mol. Reprod. Dev. 78, 436). The protein is present at all stages and in all cells with a strong nuclear staining in both species. The objective of this study was to perform an in-depth study at the blastocyst stage to compare the level of the nuclear protein between the inner cell mass (ICM) and the trophectoderm (TE) from the early to the expanded blastocyst stage. In vitro produced bovine blastocysts were collected at Day 6, Day 7.5, and Day 8 post-insemination. Hoxb9 proteins were detected by whole-mount immunofluorescence. TE nuclei were strongly stained at all stages while from D6 but especially from D7.5, the level of HOXB9 seemed to decrease in ICM nuclei with an increasing heterogeneity of staining between ICM nuclei. A light and apparently stable staining was also observed in the cytoplasm. Confocal images were quantified (Nis-element 3.1, Nikon). For each cell of TE or ICM, the ratio between the mean intensity of the nucleus and the mean intensity of the corresponding total cytoplasm was calculated. Whatever the stages, TE ratios were significantly (Mann–Whitney test; P < 0.0001) higher than ICM ratios, suggesting that HOXB9 is present in higher amounts in TE than in ICM cells. This observation could be correlated with the reduced HOXB9 relative expression observed in blastocysts. Moreover, the proportion of blastocysts showing a reduction of HOXB9 staining in at least one nucleus significantly increased from Day 6 to Day 7.5 blastocysts and Day 8 blastocysts (from 26% to 74% or 85%, chi-squared test; P < 0.001). Mouse zygotes, collected from superovulated mice, were cultured in vitro and embryos were collected 72 h, 80 h, 92 h and 100 h post-hCG injection. A similar nuclear staining was observed in all cells until 80 h post-hCG injection, while heterogeneity of staining appeared in ICM cells 92 h post-hCG, but especially in 100 h post-hCG embryos. The quantitative study was performed only on this latest stage and confirmed the stronger staining in TE than in ICM nuclei (Mann–Whitney test; P < 0.0001) observed in the bovine. At this stage, 82% of blastocysts presented a reduced Hoxb9 staining in some or all ICM nuclei. In conclusion, Hoxb9 protein is detected in all blastocyst nuclei both in the mouse and in the bovine. However, the protein seems globally less abundant in the ICM than in the TE cells. Moreover, the percentage of bovine blastocysts showing a reduction in HOXB9 staining intensity in ICM nuclei increases with blastocyst expansion. These results suggest an involvement of Hoxb9 in cell lineage differentiation in mammals.C. S. holds a FRIA PhD grant from the FRS-FNRS (Belgium). This study is supported by the FRS-FNRS and by an Action de Recherche Concertée.

P–163 The presence of trophectodermal vesicles on expanded ICSI-derived blastocysts is a good predictor of implantation

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
O Pravdyuk ◽  
M Gryshchenko ◽  
L Shatalova ◽  
K Borodai
Keyword(s):  
Zona Pellucida ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Implantation Rate ◽  
Embryo Selection ◽  
Assisted Hatching ◽  
Ratio Test ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

Abstract Study question Is the implantation rate (IR) higher in blastocysts with trophectodermal vesicles (TVs) compared to blastocysts without TVs or euploid blastocysts with unknown spontaneous hatching status? Summary answer The blastocysts with TVs demonstrate significantly higher IR in comparison to blastocysts without TVs or euploid blastocysts with unknown spontaneous hatching status. What is known already After ICSI spontaneous hatching mainly occurs by trophectoderm cell herniation via a small slit in the zona pellucida. At the beginning of this process, TVs are formed on the outside of the zona pellucida. It was previously shown that the clinical pregnancy rate was similar after the transfer of expanded blastocysts and expanded blastocysts with TVs. But another study showed that transfer of blastocysts of more advanced hatching stages yields better pregnancy rates than expanded blastocyst transfer. It remains unclear whether there is an association between the presence of TVs and IR in the transfers of single vitrified blastocysts. Study design, size, duration This retrospective cohort study was conducted from October 2018 to November 2019 and included 477 transfers of a single vitrified blastocyst. Cases were divided into 3 groups. Group 1 included transfers of blastocysts without TVs and with assisted hatching (AH). Group 2 contained the transfers of blastocysts at TVs stage of spontaneous hatching and without AH. Group 3 consisted of transfers of the euploid blastocysts with AH performed and unknown spontaneous hatching status. Participants/materials, setting, methods The age of women was between 21 and 39. Embryo transfers following oocyte donation programs were excluded from the study. This study included only transfers of the ICSI-derived fully expanded blastocysts with top-graded inner cell mass and trophectoderm. AH was performed using laser Saturn 3. The primary outcome was the implantation rate. Statistical analysis was performed using Pearson’s chi-square test and likelihood ratio test. Preimplantation genetic testing for aneuploidy (PGT-A) was performed by next-generation sequencing. Main results and the role of chance The number of cases in groups 1,2 and 3 was 133, 49, and 295, respectively. The average age in the groups was about 32.5 and did not differ between groups. The implantation rate in group 3 with PGT-A was 60% (177 out of 295), which was insignificantly higher compared to group 1 - 55% (73 out of 133) (p = 0.34). In group 2, the implantation rate was 76% (38 out of 49), which exceeded significantly the outcomes in groups 1 and 2 (p = 0.016). Thus the transfer of expanded blastocyst with TVs gives higher IR in comparison to expanded blastocyst. Therefore TVs could be utilized as a morphological marker for embryo selection. Furthermore, according to obtained results the presence of TVs on nontested blastocysts predicts implantation better than euploidy does in blastocysts with unknown spontaneous hatching status. Limitations, reasons for caution This is a retrospective nonrandomized study with its inherited limitations. Wider implications of the findings: Based on the results of the study embryo selection practice could be optimized. To maximize the outcomes of PGT-A programs embryo culture and biopsy workflow could be modified to allow collecting data on spontaneous hatching and TVs presence before performing the biopsy. Trial registration number Not applicable

Cerium oxide nanoparticles (CeO2 NPs) improve the developmental competence of in vitro-matured prepubertal ovine oocytes

2017 ◽  
Vol 29 (5) ◽  
pp. 1046 ◽  
Author(s):  
F. Ariu ◽  
L. Bogliolo ◽  
A. Pinna ◽  
L. Malfatti ◽  
P. Innocenzi ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Cumulus Cells ◽  
Developmental Competence ◽  
Nuclear Maturation ◽  
Maturation Medium ◽  
Group A ◽  
Chromatin Configuration ◽  
Development In Vitro

The present study investigated whether supplementation with different doses of cerium dioxide nanoparticles (CeO2 NPs) during in vitro maturation (IVM) of prepubertal ovine oocytes influenced their embryonic development in vitro. Cumulus–oocyte complexes derived from the ovaries of slaughtered prepubertal sheep underwent IVM with CeO2NPs (0, 44, 88 or 220 µg mL–1). Matured oocytes were fertilised in vitro and zygotes were cultured for 7 days. The results demonstrated that CeO2NPs were internalised in the cumulus cells and not in the oocyte. The treatment with CeO2NPs did not affect nuclear maturation or intracellular levels of reactive oxygen species of the oocytes. The percentage of oocytes with regular chromatin configuration and cytoskeleton structures when treated with 44 µg mL–1 CeO2NPs was similar to oocytes matured in the absence of CeO2NPs and significantly higher than those treated with 88 or 220 µg mL–1 CeO2NPs. The relative quantification of transcripts in the cumulus cells of oocytes matured with 44 µg mL–1 CeO2NPs showed a statistically lower mRNA abundance of BCL2-associated X protein (BAX), B-cell CLL/lymphoma 2 (BCL2) and superoxide dismutase 1 (SOD1) compared with the 0 µg mL–1 CeO2 NPs group. A concentration of 44 µg mL–1 CeO2NPs significantly increased the blastocyst yield and their total, inner cell mass and trophectoderm cell numbers, compared with the 0 and 220 µg mL–1 groups. A low concentration of CeO2NPs in the maturation medium enhanced in vitro embryo production of prepubertal ovine oocytes.

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