115 research outputs found
The impact of sars-cov-2 on sperm cryostorage, theoretical or real risk?
Cryopreservation of human gametes and embryos as well as human reproductive tissues has been characterized as an essential process and aspect of assisted reproductive technology (ART). Notably, sperm cryopreservation is a fundamental aspect of cryopreservation in oncological patients or patients undergoing gonadotoxic treatment. Given that there is a risk of contamination or cross-contamination, either theoretical or real, during the procedures of cryopreservation and cryostorage, both the European Society for Human Reproduction and Embryology (ESHRE) and the American Society for Reproductive Medicine (ASRM) have provided updated guidelines for preventing or reducing the contamination risk of sexually transmitted viruses. Given the ongoing and worldwide COVID-19 pandemic, there is considerable interest in what measures should be taken to mitigate SARS-CoV-2 contamination during cryopreservation and cryostorage of semen samples. The SARS-CoV-2 virus is the virus that causes COVID-19, and whose transmission and infection is mainly aerosol-mediated. Several ART professional societies, including ESHRE and ASRM have proposed measures to mitigate the spread of the SARS-CoV-2 virus. Whether the proposed safety directives are enough to mitigate the possible SARS-CoV-2-contamination of sperm samples during cryopreservation or whether the policies should be re-evaluated will be discussed in this review. Additionally, insights regarding the possible impact of COVID-19 vaccination on the safety of sperm cryopreservation will be discussed
The effect of cigarette smoking, alcohol consumption and fruit and vegetable consumption on IVF outcomes: A review and presentation of original data
Background - Lifestyle factors including cigarette smoking, alcohol consumption and nutritional habits impact on health, wellness, and the risk of chronic diseases. In the areas of in-vitro fertilization (IVF) and pregnancy, lifestyle factors influence oocyte production, fertilization rates, pregnancy and pregnancy loss, while chronic, low-grade oxidative stress may underlie poor outcomes for some IVF cases. Methods - Here, we review the current literature and present some original, previously unpublished data, obtained from couples attending the PIVET Medical Centre in Western Australia. Results - During the study, 80 % of females and 70 % of male partners completed a 1-week diary documenting their smoking, alcohol and fruit and vegetable intake. The subsequent clinical outcomes of their IVF treatment such as quantity of oocytes collected, fertilization rates, pregnancy and pregnancy loss were submitted to multiple regression analysis, in order to investigate the relationship between patients, treatment and the recorded lifestyle factors. Of significance, it was found that male smoking caused an increased risk of pregnancy loss (p = 0.029), while female smoking caused an adverse effect on ovarian reserve. Both alcohol consumption (β = 0.074, p < 0.001) and fruit and vegetable consumption (β = 0.034, p < 0.001) had positive effects on fertilization. Conclusion - Based on our results and the current literature, there is an important impact of lifestyle factors on IVF clinical outcomes. Currently, there are conflicting results regarding other lifestyle factors such as nutritional habits and alcohol consumption, but it is apparent that chronic oxidative stress induced by lifestyle factors and poor nutritional habits associate with a lower rate of IVF success
Corrigendum to “An automated blastomere identification method for the evaluation of day 2 embryos during IVF/ICSI treatments'' [Computer Methods and Programs in Biomedicine, 156 (2018) pp. 53–59](S016926071730843X)(10.1016/j.cmpb.2017.12.022)
“The authors wish to acknowledge financial support provided by the Research Committee of Technological Education Institute (TEI) of Central Mecedonia, Greece, under grant SAT/IC/030517-56/01”. © 201
An automated blastomere identification method for the evaluation of day 2 embryos during IVF/ICSI treatments
Purpose Evaluation of human embryos is one of the most important challenges in vitro fertilization (IVF) programs. The morphology and the morphokinetic parameters of the early cleaving embryo are of critical clinical importance. This stage spans the first 48 h post-fertilization, in which the embryo is dividing in smaller blastomeres at specific time-points. The morphology, in combination with the symmetry of the blastomeres seems to be powerful features with strong prognostic value for embryo evaluation. To date, the identification of these features is based on human inspection in timed intervals, at best using camera systems that simply work as surveillance systems without any precise alerting and decision support mechanisms. The purpose of the study presented in this paper was to develop a computer vision technique to automatically detect and identify the most suitable cleaving embryos (preferably at day 2 post-fertilization) for embryo transfer (ET) during IVF/ICSI treatments. Methods and results To this end, texture and geometrical features were used to localize and analyze the whole cleaving embryo in 2D grayscale images captured during in vitro embryo formation. Because of the ellipsoidal nature of blastomeres, the contour of each blastomere was modeled with an optimal fitting ellipse while the mean eccentricity of all ellipses is computed. The mean eccentricity in combination with the number of blastomeres forms the feature space on which the final criterion for the embryo evaluation was based. Conclusions Experimental results with low quality 2D grayscale images demonstrated the effectiveness of the proposed technique and provided evidence of a novel automated approach for predicting embryo quality. © 201
Complications of polycystic ovary syndrome in assisted reproduction technology
[No abstract available
Exogenous progesterone for LH surge prevention is redundant in ovarian stimulation protocols
During ovarian stimulation for IVF–embryo transfer treatment, a premature LH surge may lead to progesterone elevation that disrupts endometrial maturation and affects the probability of pregnancy following fresh embryo transfer. Preventing this LH surge and progesterone elevation using gonadotrophin-releasing hormone (GnRH) analogues is considered a standard practice. The same policy applies to cycles in which the ‘freeze-all’ protocol has been selected from the outset (e.g. donors), but the need for this has not been discussed. Moreover, in ‘freeze-all’ cycles, exogenous progesterone administration tends to replace GnRH antagonists, without reducing efficacy after embryo transfer in frozen-thawed cycles. Nevertheless, as exogenous progesterone is expected to have the same impact on the endometrium as endogenous progesterone, it is clear that, unlike in fresh cycles, in ‘freeze-all’ cycles an endogenous LH surge prevention does not seem necessary. Therefore, both GnRH antagonists and exogenous progesterone appear to be redundant in ‘freeze-all’ cycles, and in this context the indications for the use of GnRH analogues in ovarian stimulation protocols need to be revisited. © 202
Response to: Premature ovulation; is any risk small enough to take when avoidable?
[No abstract available
Genes and conditions controlling mammalian pre-and post-implantation embryo development
Embryo quality during the in vitro developmental period is of great clinical importance. Experimental genetic studies during this period have demonstrated the association between specific gene expression profiles and the production of healthy blastocysts. Although the quality of the oocyte may play a major role in embryo development, it has been well established that the post-fertilization period also has an important and crucial role in the determination of blastocyst quality. A variety of genes (such as OCT, SOX2, NANOG) and their related signaling pathways as well as transcription molecules (such as TGF-β, BMP) have been implicated in the pre-and post-implantation period. Furthermore, DNA methylation has been lately characterized as an epigenetic mark since it is one of the most important processes involved in the maintenance of genome stability. Physiological embryo development appears to depend upon the correct DNA methylation pattern. Due to the fact that soon after fertilization the zygote undergoes several morphogenetic and developmental events including activation of embryonic genome through the transition of the maternal genome, a diverse gene expression pattern may lead to clinically important conditions, such as apoptosis or the production of a chromosomically abnormal embryo. The present review focused on genes and their role during pre-implantation embryo development, giving emphasis on the various parameters that may alter gene expression or DNA methylation patterns. The pre-implantation embryos derived from in vitro culture systems (in vitro fertilization) and the possible effects on gene expression after the prolonged culture conditions are also discussed. ©2015 Bentham Science Publishers
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