Chemical removal of the outside of the zona pellucida of day 3 human embryos has no impact on implantation rate

1993 ◽  
Vol 10 (3) ◽  
pp. 187-191 ◽  
Author(s):  
Michael J. Tucker ◽  
Nicole M. Luecke ◽  
Sharon R. Wiker ◽  
Graham Wright
Keyword(s):  
Zona Pellucida ◽  
Implantation Rate ◽  
Human Embryos

P–206 Does oocyte vitrifcation affect morphokinetics of subsequent embryo development?

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
S Montgomery ◽  
K Montgomery ◽  
D Nash ◽  
A Campbell
Keyword(s):  
Embryo Development ◽  
Live Birth ◽  
Developmental Stages ◽  
Controlled Trial ◽  
Implantation Rate ◽  
Clinical Pregnancy ◽  
Human Embryos ◽  
Early Cleavage ◽  
Oocyte Vitrification ◽  
Early Developmental

Abstract Study question Are the morphokinetic profiles, as assessed using time-lapse technology, of human embryos developed from vitrified oocytes different to those from fresh oocytes. Summary answer Vitrification of oocytes does have an effect on early developmental morphokinetic profiles, but this is normalized by the time the embryo has reached blastocyst. What is known already Vitrification of oocytes is now commonplace, but little is known about the effect this may have on subsequent embryo development. Study design, size, duration This was a retrospective data analysis, from 8 fertility clinics in the UK between 2012 and 2019. Embryos from patients in the vitrified group (n = 557) were matched to fresh patient controls (n = 539). The matching was performed based on the following criteria: type of treatment, patient age, cause of infertility and number of embryos. Participants/materials, setting, methods The embryos in each group were compared for mean morphokinetics of key developmental stages in hours post insemination (hpi). Parameters compared included early cleavage divisions (t2-t8), time to start of compaction (tSC), time to morula (tM), time to start blastulation (tSB), time to full blastocyst (tB) and duration of compaction (tB-tSC). Treatment outcomes were compared between the two groups, including percentage of blastocyst formation, clinical pregnancy rate, implantation rate and live birth rate. Main results and the role of chance The results showed a significant delay across all early cleavage divisions as follows for vitrified and fresh oocytes respectively: 2-cell (28.14 vs 26.10 (p < 0.001)), 3 cell (37.56 vs 35.37 (p < 0.001)), 4 cell (40.58 vs 37.54 (p < 0.001)), 5 cell (50.31 vs 47.14 (p < 0.001)), 6 cell (53.99 vs 50.87 (p < 0.001)), 7 cell (57.08 vs 54.48 (p < 0.001)) and 8 cell (61.26 vs 58.91 (p < 0.01)). In addition, tSC was also significantly delayed in the vitrified group (80.65 vs 76.36 (p < 0.001)). However, the compaction stage was significantly shorter in the vitrified oocytes (19.02 vs 22.45 (p < 0.001)). Therefore, there was no difference in the time that embryos derived from fresh and vitrified oocytes reached the blastocyst stage (108.03 vs 107.78 (p > 0.05)). No difference was found in clinical pregnancy, implantation or live birth rates but significantly fewer blastocyst developed from vitrified oocytes compared to fresh (36.09% vs 42.4% (p < 0.05)). Limitations, reasons for caution Although this was a matched analysis, it was a retrospective in nature therefore is subject to confounders. However, it would be problematic to perform a prospective randomized controlled trial to address this study question given the need to randomize patients to elective freezing of oocytes prior to embryo creation. Wider implications of the findings: Vitrification of oocytes may affect early developmental morphokinetic profiles, but any effect is normalized by the time the embryo has reached blastocyst. However, fewer blastocysts may develop following oocyte vitrification. This may have implications for oocyte donation banks and those patients choosing to cryopreserve oocytes. Trial registration number NA

Domestic cat embryos generated without zona pellucida are capable of developing in vitro but exhibit abnormal gene expression and a decreased implantation rate

2021 ◽  
Author(s):  
Daniel Veraguas-Davila ◽  
Maria Francisca Cordero ◽  
Soledad Saez ◽  
Darling Saez-Ruiz ◽  
Alejandro Gonzalez ◽  
...  
Keyword(s):  
Gene Expression ◽  
Zona Pellucida ◽  
Implantation Rate ◽  
Domestic Cat

scholarly journals Effects of Laser Assisted Hatching on Pregnancy Outcomes of Frozen Embryo Transfer Cycles

2020 ◽  
Vol 5 (9) ◽  
pp. 1223-1223
Author(s):  
Dr. Narmadha. R ◽  
Dr . Manjula ◽  
Dr. N.Sanjeeva Reddy ◽  
Dr. Sindhuja. N.S
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Zona Pellucida ◽  
Implantation Rate ◽  
Frozen Embryo Transfer ◽  
Control Group ◽  
Assisted Hatching ◽  
Younger Women ◽  
The Mean ◽  
Baseline Characteristics

The implantation of the embryo into the uterus requires hatching from its zona pellucida (ZP). The inability of the embryo to break its zona pellucida is considered as a factor for implantation failure. Assisted hatching (AH) is performed to make it easier for natural hatching to occur, also providing early embryoendometrium contact, which favors the embryos implantation into the uterus. To evaluate the effect of laser assisted hatching (LAH) on pregnancy rate in frozen embryo transfer cycle.  Materials & methods: In a prospective observational study a total of 80 patients who underwent frozen embryo transfer(FET) cycles were included in the study. Patients were divided into Laser assisted hatching group (LAH) and no LAH group. In the LAH group, zona thinning was done with the help of laser just prior to the embryo transfer. In the control group no hatching was done before transfer. The main outcome measures were pregnancy rate & implantation rate. The baseline characteristics of the 80 patients included in the study ie.,LAH group (n=40) vs no LAH group (n=40),the mean age ( 30.855.4 vs 333.9),mean BMI (25.64.1 vs 27.94.5),duration of infertility ( 6.184.1 vs 8.534.7) , number of embryos transferred (2.750.8 vs 2.70.72) respectively. Younger women < 30 years in no LAH group had higher pregnancy rate compared to the LAH group. Between the two groups, patients between 31-35 years in LAH group had higher pregnancy rate compared to no LAH group. The pregnancy rate (42.85% vs 54.5%) in LAH group of women >35years found lower than the no LAH group. LAH seems to be beneficial in women between 31- 35 years of age group, but LAH does not seem to be beneficial in women > 35 years of age. There is slight increase in pregnancy rates with laser assisted zona thinning in frozen transfer cycle, but it is not statistically significant.

scholarly journals Use of co-culture of human embryos on Vero cells to improve clinical implantation rate

1999 ◽  
Vol 14 (suppl 2) ◽  
pp. 112-120 ◽  
Author(s):  
A. Veiga ◽  
M.J. Torello ◽  
Y. Menezo ◽  
A. Busquets ◽  
O. Sarrias ◽  
...  
Keyword(s):  
Implantation Rate ◽  
Vero Cells ◽  
Human Embryos

scholarly journals Post-warming survival rates and clinical outcomes of human cleavage stage embryos vitrified/warmed using CryoTouch and Cryotop methods

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Somayeh Keshavarzi ◽  
Azadeh Dokht Eftekhari ◽  
Hajar Vahabzadeh ◽  
Marzieh Mehrafza ◽  
Robabeh Taheripanah ◽  
...  
Keyword(s):  
Retrospective Study ◽  
Survival Rate ◽  
Clinical Outcomes ◽  
Live Birth ◽  
Survival Rates ◽  
Implantation Rate ◽  
Clinical Pregnancy ◽  
Human Embryos ◽  
Cleavage Stage ◽  
Embryo Survival

Abstract Background Vitrification has become the method of choice for cryopreservation of human embryos and gametes. There are multiple commercial media, containing different combinations and concentrations of cryoprotectants, available for vitrification and warming procedures. The aim of this retrospective study was to compare post-warming survival rate and clinical outcomes of cleavage stage embryos vitrified/warmed using two different commercial methods (CryoTouch and Cryotop) during intracytoplasmic sperm injection/frozen embryo transfer (ICSI/FET) cycles. This retrospective study evaluated a total of 173 FET cycles performed on 446 warmed cleavage stage embryos between January 2018 and December 2020. Post-warming embryo survival rate and clinical outcomes including clinical pregnancy, implantation, and live birth rates were calculated. Results The results showed no significant differences between two groups in terms of post-warming survival rate (p value = 0.5020), clinical pregnancy rate (p value = 0.7411), implantation rate (p value = 0.4694), and live birth rate (p value = 0.5737). Conclusions Collectively, high successful rates were observed in outcomes of vitrified/warmed cleavage stage embryos using both CryoTouch and Cryotop commercial methods.

scholarly journals Influence of EmbryoGlue® transfer medium on implantation of human embryos

2021 ◽  
Vol 52 (2) ◽  
pp. 119-123
Author(s):  
Dragana Pavlović-Vasić ◽  
Sanja Sibinčić ◽  
Irena Milaković ◽  
Sanja Lukač ◽  
Saša Vujnić ◽  
...  
Keyword(s):  
Smoking Status ◽  
Embryo Implantation ◽  
Medical Science ◽  
Implantation Rate ◽  
Blastocyst Stage ◽  
In Vitro Fertilisation ◽  
Human Embryos ◽  
Control Group ◽  
Conventional Medium

Introduction: Thanks to ever-growing advances in medical science, couples who are in the in vitro fertilisation (IVF) now have more options than ever to encase their chances at a successful pregnancy. One of the options is the use of EmbryoGlue (EG), that creates a bridge between the embryo and the uterus and provides protection to the embryo itself during the transfer process. Aim of this study was to determine whether EG medium is of greater importance for embryo implantation than conventional medium in assisted reproductive technology and compare the rate of embryo implantation with EG and conventional medium in relation to the quality of the embryo, the age of the patients and tobacco smoking. Methods: The retrospective study included 50 patients who used EG medium in embryo transfer (ET) and 50 patients in the control group using conventional medium. All patients underwent ET after stimulation of the cycle according to a short protocol. ETs were done on Day 2, 3, or 5 in the blastocyst stage. Age and smoking status were recorded. Results: Out of a total of 100 patients, 42 patients had successful implantation and positive b-hCG 15 days after ET. In a control group 38 % had positive b-hCG and in the group of patients who used EG 46 %. A higher rate of embryo implantation success was observed on the second day of transfer in the group of patients using EG. In the EG group a significant increase in the embryo implantation rate was observed in patients older than 35. In tobacco smokers the implantation rate was higher if they used EG during ET. Conclusion: EG medium had a positive effect on the second day of ET, patients above the age of 35 and patients who were tobacco smokers.

P–216 Successful pregnancies and deliveries in patients with a recurrent failure of ART treatments following artificial removal of the zona pellucida (ZP) at the pronuclear stage

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Y Mio ◽  
K Yumoto ◽  
T Shimura ◽  
M Sugishima ◽  
M Nakaoka ◽  
...  
Keyword(s):  
Zona Pellucida ◽  
Culture Method ◽  
Oocyte Retrieval ◽  
Time Lapse ◽  
Poor Quality ◽  
Blastocyst Transfer ◽  
Human Embryos ◽  
Culture Methods ◽  
Conventional Culture

Abstract Study question Can a novel embryo culture method that artificially removes the ZP at the pronuclear stage yield successful pregnancy in patients with poor-quality embryos and/or blastocysts? Summary answer A blastocyst transfer after ZP-free culture can result in pregnancy for patients who cannot obtain good quality blastocysts from conventional culture methods. What is known already Perivitelline threads are been associated with the formation of cytoplasmic fragments. We had previously observed perivitelline threads in the adhesive region between the ooplasm and the ZP at the first cleavage in human embryos. We removed the ZP at the pronuclear stage in 71 abnormally fertilized oocytes (zygotes with three pronuclei), donated after conventional IVF (c-IVF), and termed them ZP-free 3PN. We found ZP-free 3PN embryos could be cultured without losing blastomere adhesions. Furthermore, the rate of good quality embryos was significantly higher in ZP-free 3PN embryos compared with ZP-intact embryos (ZP-intact 2PN/2PB and 3PN embryos; P &lt; 0.05). Study design, size, duration This study was conducted in two cases selected among patients who underwent ART treatment in our clinic between 2018 and 2019. Cases were selected if they lacked good quality blastocysts in previous c-IVF/Intracytoplasmic Sperm Injection (ICSI) cycles due to massive cytoplasmic fragmentation at the first and second cleavage. We performed a clinical trial of ZP-free culture from December 2019 to March 2020. Participants/materials, setting, methods Two cases were selected for this trial. Normally fertilized oocytes were grouped as ZP-free or ZP-intact. For the ZP-free group, 2PN embryos were placed in 0.125M sucrose-containing HEPES to reduce ooplasm size, then ooplasms were completely separated from ZPs by a laser and pipetting. ZP-free and ZP-intact embryos were cultured with time-lapse imaging for up to seven days. Resultant blastocysts were either transferred into uterus or cryopreserved on Day5/6/7 for future embryo transfer cycles. Main results and the role of chance The ZP-free culture method was applied to two patients (patient A and B) with recurrent failure of ART in our clinic due to poor-quality embryos and/or difficulties in obtaining good quality blastocysts. In both cases, blastocysts were successfully obtained and cryopreserved for all ZP-free culture cycles. In patient A, one good quality ZP-free blastocyst was freshly transferred five days after oocyte retrieval, and a live male baby (2925g) was delivered at 40 weeks of gestation by caesarean section). In patient B, a frozen/thawed ZP-free blastocyst transfer was conducted, and a live female baby (3225g) was delivered at 39 weeks of gestation by vaginal delivery. This shows ZP-free culturing may help obtain viable embryos in patients for which conventional in vitro culturing methods result in embryos characterized with severe cytoplasmic fragmentation and poor quality in the early cleavage stage. Limitations, reasons for caution Although successful pregnancies and deliveries were confirmed in two cases, postnatal evaluations will be absolutely necessary for infants derived from ZP-free culture. In addition, the number of trial cases needs to be expanded, however careful selection of suitable patients is necessary for this novel culture method. Wider implications of the findings: We found removing the ZP at the pronuclear stage improved embryo development and led to successful pregnancies and deliveries after blastocyst transfer. This indicates ZP-free culturing may be an effective method for decreasing cytoplasmic fragmentation caused by perivitelline threads or adhesion between the ooplasm and the zona pellucida. Trial registration number Not applicable

P–135 Artificial neural networks (ANNs) for live birth prediction in frozen embryo transfers: the strength of post-warmed blastocyst dynamics

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
L Alegre ◽  
L Bori ◽  
A Coello ◽  
A S Ferreira ◽  
J C Rocha ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Neural Networks ◽  
Embryo Transfer ◽  
Live Birth ◽  
Zona Pellucida ◽  
Learning Algorithm ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Implantation Rate ◽  
Frozen Embryo Transfers

Abstract Study question Does the post-warmed blastocyst dynamics have an impact over the likelihood of achieving a live birth? Summary answer Variables related to dynamics of vitrified/warmed blastocysts have shown a greater effect on the live birth prediction than only embryo morphological quality through artificial intelligence. What is known already Morphological dynamics of vitrified/warmed blastocysts were described by Coello et al., in 2017. The investigated markers were the thickness of zona pellucida (µm) and blastocysts area (µm2) after warming and before transfer, the area of the inner cell mass (µm2), time of initiation of reexpansion (in minutes), and presence of collapse or contraction. They found a correlation between blastocyst reexpansion and implantation rate and developed a hierarchical model for implantation prediction. In our study, we evaluated the post-warmed blastocyst dynamics for live birth prediction by using novel artificial intelligence techniques. Study design, size, duration This retrospective analysis included 415 vitrified/warmed blastocysts with known live birth data. Blastocysts after warming were placed in EmbryoScope (Vitrolife) immediately until embryo transfer. Embryo evaluation and selection were performed by senior embryologists according to fresh blastocyst morphology (before vitrification). Then, parameters related to post-warmed blastocyst dynamics were calculated. Finally, these variables and the embryo morphological grade before the vitrification were used as input data for ANNs optimized with genetic algorithm for live birth prediction. Participants/materials, setting, methods Blastocysts were vitrified and warmed by the Cryotop method (Kitazato,Biopharma). During the period between the warming procedure and the embryo transfer, the following variables were measured with the drawing tools provided by the EmbryoViewer workstation: zona pellucida thinning (µm), blastocyst expansion (um) and the speed of these two events (µm/h). Finally, multilayer perceptron neural networks were trained with data of 331 embryos by using the backpropagation learning algorithm and tested with data of 84 embryos. Main results and the role of chance We trained and tested three architectures of ANNs with different input variables as follows: post-warmed variables (thinning of the zona pellucida, blastocyst expansion, thinning speed and expansion speed) and morphological grade (A, B or C) for ANN1, only post-warmed variables for ANN2 and only morphological grade for ANN3. The highest success rate when ANNs classified embryos as positive and negative live birth (LB+ and LB-) was achieved by combining post-warmed variables and morphological grade before embryo vitrification. The general accuracies for the blind tests were: 73.8% for ANN1, 66.7% for ANN2 and 71.4% for ANN3. Likewise, this combination achieved the highest AUC on test dataset to predict LB- (0.76 for ANN1, 0.74 for ANN2 and 0.67 for ANN3). However, the ANN2 trained with only post-warmed variables showed the best capacity to predict LB+ with an AUC of 0.73 (versus 0.46 for ANN1 and 0.5 for ANN3). Limitations, reasons for caution The main limitation is the subjectivity of manual annotations, although only one embryologist participated in this task. Wider implications of the findings: The dynamics of vitrified/warmed blastocysts prior to embryo transfer could be more relevant variables than the morphological quality on day 5 before the cryopreservation. The analysis of embryo behavior after warming could improve clinical outcomes in frozen embryo transfers. Trial registration number none

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