Assessment of successful pregnancy using granular oocytes in ICSI treatments

Zygote ◽  
2019 ◽  
Vol 27 (02) ◽  
pp. 97-100
Author(s):  
P. Tulay ◽  
H. Arslan ◽  
A. Buran ◽  
Y. Koprulu

SummaryDifferent parameters affect the success of assisted reproduction technology (ART) treatments. One of the advantages of using intracytoplasmic sperm injection (ICSI) is that it also enables the assessment of the oocyte morphology. To date there has not been a clear conclusion on aberrant oocyte morphology and its consequences on the success of ART treatments. Therefore, in this study, we aimed to investigate the fertilization, embryo development and pregnancy rates in patients who have oocytes with granular cytoplasm. Additionally, we investigated if there were more aneuploid embryos obtained from abnormal cytoplasmic morphology. In total, 5704 oocytes were collected and, of these, 4036 were metaphase II (MII) oocytes. The morphology of these oocytes was assessed following denudation and 970 oocytes were observed to have granular cytoplasm. There was no difference in the fertilization rates between the oocytes with normal cytoplasm (89%) and oocytes with granular cytoplasm (72%). Cleavage of embryos and the number of embryos that reached the blastocyst stage were also similar in these two groups. The aneuploidy rates between the two groups were also similar. However, clinical pregnancies were significantly lower in embryos obtained from oocytes with granular cytoplasm (37.5% vs 70%, P<0.05). Therefore, the morphology of the oocyte is as important as morphology of the sperm. Even though normal fertilization and cleavage were achieved from oocytes with granular cytoplasm, their implantation potential was significantly compromised.

2021 ◽  
Vol 9 (2) ◽  
pp. 18
Author(s):  
Ioanna Bouba ◽  
Elissavet Hatzi ◽  
Paris Ladias ◽  
Prodromos Sakaloglou ◽  
Charilaos Kostoulas ◽  
...  

Applications and indications of assisted reproduction technology are expanding, but every new approach is under scrutiny and thorough consideration. Recently, groups of assisted reproduction experts have presented data that support the clinical use of mosaic preimplantation embryos at the blastocyst stage, previously excluded from transfer. In the light of published contemporary studies, with or without clinical outcomes, there is growing evidence that mosaic embryos have the capacity for further in utero development and live birth. Our in-depth discussion will enable readers to better comprehend current developments. This expansion into the spectrum of ART practices requires further evidence and further theoretical documentation, basic research, and ethical support. Therefore, if strict criteria for selecting competent mosaic preimplantation embryos for further transfer, implantation, fetal growth, and healthy birth are applied, fewer embryos will be excluded, and more live births will be achieved. Our review aims to discuss the recent literature on the transfer of mosaic preimplantation embryos. It also highlights controversies as far as the clinical utilization of preimplantation embryos concerns. Finally, it provides the appropriate background to elucidate and highlight cellular and genetic aspects of this novel direction.


2019 ◽  
Vol 31 (12) ◽  
pp. 1862 ◽  
Author(s):  
N. A. Martino ◽  
G. Marzano ◽  
A. Mastrorocco ◽  
G. M. Lacalandra ◽  
L. Vincenti ◽  
...  

Time-lapse imaging was used to establish the morphokinetics of equine embryo development to the blastocyst stage after invitro oocyte maturation (IVM), intracytoplasmic sperm injection (ICSI) and embryo culture, in oocytes held overnight at room temperature (22–27°C; standard conditions) before IVM. Embryos that developed to the blastocyst stage underwent precleavage cytoplasmic extrusion and cleavage to the 2-, 3- and 4-cell stages significantly earlier than did embryos that arrested in development. We then determined the rate of blastocyst formation after ICSI in oocytes held for 2 days at either 15°C or room temperature before IVM (15-2d and RT-2d treatment groups respectively). The blastocyst development rate was significantly higher in the 15-2d than in the RT-2d group (13% vs 0% respectively). The failure of blastocyst development in the RT-2d group precluded comparison of morphokinetics of blastocyst development between treatments. In any condition examined, development to the blastocyst stage was characterised by earlier cytoplasmic extrusion before cleavage, earlier cleavage to 2- and 4-cell stages and reduced duration at the 2-cell stage compared with non-competent embryos. In conclusion, this study presents morphokinetic parameters predictive of embryo development invitro to the blastocyst stage after ICSI in the horse. We conclude that time-lapse imaging allows increased precision for evaluating effects of different treatments on equine embryo development.


2008 ◽  
Vol 20 (1) ◽  
pp. 215
Author(s):  
J. L. Altermatt ◽  
T. K. Suh ◽  
J. E. Stokes ◽  
L. F. Campos-Chillon ◽  
E. M. Carnevale

Reduced fertility in aged mares is associated with delayed early embryo development and lower pregnancy rates, potentially related to oocyte developmental competence. Human oocyte morphology has been associated with developmental potential, although comparative evidence is lacking in the mare. Exogenous FSH may be beneficial in obtaining more oocytes; however, effects on oocyte morphology and competence are unknown. Objectives were to determine if zona pellucida thickness (ZPT), ooplasm volume (OV), and perivitelline space volume (PVSV) were related to mare age or FSH treatment and to cleavage, blastocyst, and pregnancy rates after intracytoplasmic sperm injection (ICSI). Cycles with and without eFSH treatment were alternated; eFSH treatments began in diestrus with a cohort of follicles ≥20 mm. Oocytes were collected by transvaginal aspiration from follicles >30 mm from young (4 to 9 years) and old (>20 years) mares at 20 to 24 h after administration of recombinant eLH. Oocytes were cultured for 18 h in TCM-199 at 38.5�C in 6% CO2 in air. Sperm were injected 40 � 1 h after eLH, using frozen sperm from a single ejaculate. Presumptive zygotes were incubated in Dulbecco's modified Eagle's medium/F12 + 10% fetal calf serum at 38.5�C in 5% CO2, 5%O2, and 90% N2. Cleavage (≥2 cells) was recorded 48 h after ICSI. Blastocysts considered viable (formation before 9 d and good quality) were transferred nonsurgically into recipients 3 to 7 days after ovulation. Only pregnancies of fetuses with heart beats were included. Morphological parameters of oocytes (old, n = 40; young, n = 37) were obtained from photographic images taken at ICSI and analyzed by computer-assisted measurement using digital calipers (Spot Software, Diagnostic Instruments, Inc., Sterling Heights, MI, USA). Zona pellucida thickness was averaged from 2 measurements 90� to 180� apart. Ooplasm volume was calculated (4/3πr3) from the average of 2 diameters of the ooplasm 90� apart; and PVSV was calculated as the difference of the vitelline membrane volume and that of the volume at the inner volume of the ZP calculated as an oblate spheroid (4/3πa2b) from the average of 2 diameters. Zona pellucida thickness, OV, and PVSV were analyzed using 2-way ANOVA for main effects of age and treatment and 3-way ANOVA by adding cleavage as a factor. Zona pellucida thickness was less (P = 0.007) for old compared with young (least squares mean SEM of 11.4 � 0.2 and 12.3 � 0.2 µm, respectively) with no effect on cleavage, blastocyst, or pregnancy rates. Ooplasm volume was not different (P = 0.14) between old and young (309 036 � 5373 and 320 544 � 5639 µm3, respectively) and did not affect cleavage, blastocyst, or pregnancy rates. The PVSV was greater (P = 0.001) in old compared with young (157 505 � 10 853 and 102 161 � 11 388 µm3, respectively) and may be related to the lower cleavage (P = 0.03), blastocyst (P = 0.02), and pregnancy (P = 0.05) rates. Treatment with FSH had no effect (P > 0.1) on morphology or embryo development. In this study, ZPT and PVSV differed with mare age and could be of predictive value for oocyte developmental competence.


2020 ◽  
Vol 32 (5) ◽  
pp. 468 ◽  
Author(s):  
A. Claes ◽  
J. Cuervo-Arango ◽  
S. Colleoni ◽  
G. Lazzari ◽  
C. Galli ◽  
...  

The success of invitro embryo production (IVEP) in horses has increased considerably during recent years, but little is known about the effect of the speed of invitro embryo development. Blastocysts (n=390) were produced by intracytoplasmic sperm injection of IVM oocytes from warmblood mares, cryopreserved, thawed and transferred into recipient mares on Days 3, 4, 5 or 6 after ovulation. The time required for invitro-produced (IVP) embryos to reach the blastocyst stage was recorded (Day 7 vs Day 8). The likelihood of foaling was affected by the speed of invitro embryo development and recipient day after ovulation at transfer. The odds ratio for foaling was ~0.63 for transfer of Day 8 (46%) compared with Day 7 (56%) IVP blastocysts. The highest likelihood of pregnancy (72%) and foaling (60%) was observed when IVP blastocysts were transferred to recipient mares on Day 4 after ovulation. Finally, the sex (colt:filly) ratio was higher after transfer of Day 7 (71%:29%) than Day 8 (54%:46%) IVP blastocysts, suggesting that the speed of embryo development is sex dependent. In conclusion, the speed of invitro embryo development in our IVEP system affects the likelihood of foaling and the sex of the foal.


2005 ◽  
Vol 17 (2) ◽  
pp. 308
Author(s):  
M. Katayama ◽  
T. Cantley ◽  
A. Rieke ◽  
B. Day

The effect of a cysteine supplement in culture media for oocytes matured in vitro after intracytoplasmic sperm injection (ICSI) on fertilization and embryo development were examined. In the first experiment, sperm injected oocytes were cultured in NCSU23 (control) or NCSU23 supplemented with 0.57–3.71 mM cysteine (0.57–3.71 Cys) for 12 h after ICSI, and then fixed to observe pronuclear formation. In the second experiment, to examine the appropriate duration time of cysteine supplement to support fertilization, sperm-injected oocytes were transferred into NCSU23 following culture in NCSU23 supplemented with 1.71 mM cysteine for 1, 2, 3, 4, 5, 6, or 9 h after ICSI, and then fixed at 12 h. At the same time, morphological changes of sperm heads in oocytes cultured in NCSU23 (1.71 Cys) were observed. In the third experiment, to examine the developmental ability of ICSI embryos fertilized in NCSU23 (1.71 Cys), sperm injected oocytes were cultured under the following conditions for a total of 168 h; NCSU23 (control), NCSU23 (1.71 Cys) for 3 h followed by transfer into NCSU23 (1.71 Cys-3 h), NCSU23 (1.71 Cys) for 12 h followed by transfer in NCSU23 (1.71 Cys-12 h), or NCSU23 (1.71 Cys) (1.71 Cys). Data were pooled from at least five replicates. Values in each replicate were analyzed using one-way ANOVA. Significance of differences was assessed by Student's t-test. Culture with several concentrations of cysteine for 12 h showed that 1.71–3.71 Cys significantly (P < 0.05) increased fertilization rates above controls or 0.57 Cys (56–60%, 35%, or 48%, respectively). Culture for several duration times with 1.71 Cys showed that fertilization rates increased as the duration time increased to 3 h which was significantly (P < 0.05) higher than controls (68% and 34%, respectively), and culture times of greater than 3 h did not increase fertilization rates (58–68%). At 3 h, 59% of oocytes cultured in NCSU23 (1.71 Cys) had decondensed sperm heads and 16% of those had enlarged sperm heads. At 6 h, 50% of oocytes cultured in NCSU23 (1.71 Cys) had male pronuclei. Blastocyst formation rate in 1.71 Cys-3 h was 29% which was higher than for controls (20%). On the other hand, 1.71 Cys-12 h cultures showed low blastocyst formation rates, and continuous culture in NCSU23 (1.71 Cys) for 168 h (1.71 Cys) significantly (P < 0.05) decreased blastocyst rates (16% and 7%, respectively). We found that the supplement of 1.71 mM cysteine to NCSU23 for culture of oocytes after ICSI improved fertilization rates. However, the presence of 1.71 mM cysteine for 12 h or longer after ICSI had adverse effects on embryo development. Since 1.71 mM cysteine supplement for 3 h after ICSI improved blastocyst formation with the same fertilization rates as when supplemented for 12 h, the presence of cysteine only during the decondensation of sperm chromatin was found to be associated with the improvement of fertilization and also the promotion of blastocyst formation.


2017 ◽  
Vol 29 (1) ◽  
pp. 179
Author(s):  
F. Magata ◽  
K. Tsuchiya ◽  
H. Komaki ◽  
M. Konishi ◽  
A. Ideta

Reduction in oocyte quality is a major factor responsible for declining fertility with age. The abnormal fertilization rate of oocytes from aged cows was reportedly higher than that of oocytes from young cows (Iwata et al. 2011. Reprod. Fertil. Dev. 23, 424–432). We hypothesised that assisted fertilization by intracytoplasmic sperm injection (ICSI) might improve the developmental abilities of oocytes collected from aged females. The aims of the study were (1) to determine the effect of maternal aging on the ability of bovine oocytes to undergo cytoplasmic maturation, fertilization, and further embryo development; and (2) to determine whether ICSI would improve the efficiency of embryo production in aged cows. Cows aged 30 to 50 months or >120 months were defined as young or aged, respectively. Cumulus-oocyte complexes were harvested from abattoir-derived ovaries of young (40 ± 7 months, n = 89) and aged (136 ± 12 months, n = 55) Holstein cows and matured for 23 h in TCM-199 supplemented with 5% fetal bovine serum (FBS) at 38.5°C under 5% CO2 with saturated humidity. Then, surrounding cumulus cells were removed, and cortical granules in the oocyte were stained with Lens culinaris–fluorescein isothiocyanate to evaluate the cytoplasmic maturation. Matured oocytes were inseminated by IVF or ICSI. At 15 h post-insemination, the numbers of pronuclei were determined to evaluate the fertilization rates. Presumptive IVF- or ICSI-derived zygotes were cultured for 5 days in CR1aa medium with 2% FBS and subsequently in USU6 with 5% FBS for 3 days at 38.5°C in 5% O2, 5% CO2, and 90% N2 with saturated humidity. Chromosome numbers of blastocysts were counted to evaluate the effect of maternal aging on ploidy. All experiments were performed with more than 4 independent runs, and data were analysed using chi-square tests. The distribution of matured oocytes into different cortical granule classes was affected by age, with a significantly lower (P < 0.01) proportion of class III (mature cytoplasm) oocytes from aged cows (29%) compared with those from young cows (57%). Although fertilization rates following IVF did not differ between the groups, the proportion of abnormal fertilization (more than 2 pronuclei) was 32% in the aged group: higher than in the young group (15%; P < 0.01). The rates of cleaved embryos following IVF were the same among groups, but the rate of development to the blastocyst stage of oocytes from aged cows (38%) was significantly (P < 0.05) lower than in those from young cows (52%). Moreover, the proportion of diploid blastocysts with 2 sets of chromosomes (2n = 60) was lower (47%) in the aged than in the young groups (75%; P < 0.05). However, in the ICSI embryos, the rates of development to the blastocyst stage did not differ significantly between groups (young 36%; aged 43%). Thus, maternal aging might impair the cytoplasmic maturation of bovine oocytes, which could be associated with abnormal fertilization or low developmental competence. Our results also indicate possible beneficial effects of ICSI on the efficiency of embryo production in aged cows.


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