scholarly journals 93 BLASTOCYST PRODUCTION FROM BOVINE OOCYTES VITRIFIED IN A CLOSED (BIOSECURE) SYSTEM FOLLOWING IN VITRO MATURATION IN THE PRESENCE OR ABSENCE OF VITAMIN E

2005 ◽  
Vol 17 (2) ◽  
pp. 196 ◽  
Author(s):  
V.C. Moreira ◽  
G.J. McCallum ◽  
A. Ainslie ◽  
T.G. McEvoy

The value of assisted reproductive technologies intended for conservation of livestock genetics ultimately will depend on their effectiveness in both sustaining gamete/embryo viability and ensuring stringent biosecurity. This study investigated bovine oocyte survival following vitrification in a sealed system prior to storage in liquid nitrogen. It also tested the effect of supplementary vitamin E on tolerance of oocytes to vitrification procedures. Healthy COCs from abattoir-derived ovaries were matured in TCM-199 supplemented with 10% v/v fetal calf serum (FCS) in the absence (control) or presence (VitE) of 100 μM α-tocopherol (Sigma, Poole, UK) in humidified atmosphere (5% CO2 in air; 38.5°C). Between 22 and 24 h after commencement of IVM, COCs were pipetted to remove excess cumulus cells, and then equilibrated at room temperature in 7.5% DMSO plus 7.5% ethylene glycol (EG) in HEPES-buffered Holding Medium (HM; Irvine Scientific, Santa Ana, CA, USA) for 7 min before transfer to vitrification solution (15% DMSO, 15% EG, and 0.5 M sucrose in HM; Irvine Scientific). Loading of oocytes (n = 78 control and 85 VitE) into CryoTips (Irvine Scientific) and heat-sealing (each end) was achieved within 90 s, with tips then plunged into liquid nitrogen. Subsequent warming and cryoprotectant removal were at room temperature in HM with 1 M sucrose for 2 min, 0.5 M sucrose for 4 min, and HM alone for 6 min. Oocytes were allowed recover for approximately 3 h in TCM-199 with 20% FCS (5% CO2 in air; 38.5°C), and then fertilized in vitro (single sire). After 22 h (Day 1) presumptive zygotes were transferred to SOF containing fatty acid-free BSA (4 mg mL−1) and incubated for up to 8 days (5% O2, 5% CO2, 90% N2; 38.5°C). Cleavage data (Day 2) and blastocyst yields (Days 7 to 9) were analyzed by chi-square test. In addition to those that were vitrified, some oocytes (n = 9 per treatment) were observed via video to permit analysis (ImageJ; NIH, USA) of volume excursions during the 7 min immediately following initial exposure to HM with 7.5% DMSO plus 7.5% EG. Data were compared using ANOVA. Overall incidence of cleavage by Day 2 was 45% (range: 36 to 51%) and 35% (31 to 43%) for control and VitE, respectively, (NS). Day 7 and total control blastocyst yields were 7.4% and 18.5%, respectively; corresponding yields for VitE were 19% and 25% (control vs. VitE, NS). Video evidence indicated that although Control oocytes invariably reached minimal volume later than VitE oocytes (30 vs. 20 s), in each case this was 52% of initial size. By 7 min, both had similar volumes, the respective means being 94% and 92% of initial size. In the present study provision of vitamin E during IVM did not significantly enhance the subsequent resilience and development of oocytes subjected to a vitrification protocol. However, this protocol achieved efficient and biosafe bovine gamete storage. This work was funded by SEERAD; CryoTips and vitrification solutions were donated by Irvine Scientific; VCM was supported by MLC, UK.

1991 ◽  
Vol 3 (2) ◽  
pp. 175 ◽  
Author(s):  
R Li ◽  
A Trounson

This study investigates the effects of time and temperature of exposure to a high concentration (4.5 M) of dimethyl sulfoxide (DMSO), glycerol, 1,2-propanediol (PROH), or a mixture of DMSO and glycerol (DG) in a solution containing 0.25 M sucrose, on the survival and development of rapidly frozen mouse blastocysts. Embryos had significantly (P less than 0.01) higher rates of survival and development when exposed to cryoprotectant at 0 degree C compared with room temperature. The time of exposure to cryoprotectant at either 0 degree C or room temperature before being plunged into liquid nitrogen significantly (P less than 0.01) affected the survival and development of frozen-thawed embryos. Survival and development of blastocysts in vitro and in vivo was significantly (P less than 0.05) higher when exposed at 0 degree C for 10 min to DG, DMSO and glycerol than to PROH. It is concluded that, unlike early-cleavage stage embryos, blastocysts need to be equilibrated at a low temperature (0 degree C) with high concentrations of cryoprotectant before rapid freezing. Exposure of blastocysts to 4.5 M cryoprotectant and 0.25 M sucrose at room temperature either was toxic or else markedly reduced their viability after freezing and thawing, depending on the duration of the initial exposure.


Zygote ◽  
2003 ◽  
Vol 11 (4) ◽  
pp. 361-366 ◽  
Author(s):  
Csaba Pribenszky ◽  
Sándor Cseh ◽  
Zsolt Abonyi-Tóth ◽  
László Solti

The objective of the present study was to examine the effect of rapid freezing on the in vitro and in vivo survival of zona-pellucida-free hatched mouse blastocysts. Hatched blastocysts were rapidly frozen in a freezing medium containing either ethylene glycol (EG) or glycerol (G) in 1.5 M or 3 M concentration. Prior to freezing, embryos were equilibrated in the freezing medium for 2 min, 10 min, 20 min or 30 min at room temperature. To freeze them, embryos were held in liquid nitrogen vapour [≈1 cm above the surface of the liquid nitrogen (LN2)] for 2 minutes and then immersed into LN2. After thawing, embryos were transferred either to rehydration medium (DPBS + 10% foetal calf serum + 0.5 M sucrose) for 10 minutes or rehydrated directly in DPBS supplemented with foetal calf serum. In vitro survival of embryos frozen with EG was higher than those frozen with G. The highest survival was obtained with 3 M EG and 2 min or 10 min equilibration prior to freezing, combined with direct rehydration after thawing. Frozen blastocysts developed into normal foetuses as well as unfrozen control ones did, with averages of 30% (control), 26% (EG) and 15% (G). The results show that hatching and hatched mouse blastocysts can be cryopreserved by a simple rapid freezing protocol in EG without significant loss of viability. Our data indicate that the mechanical protection of the zona pellucida is not needed during freezing in these stages.


GYNECOLOGY ◽  
2018 ◽  
Vol 20 (1) ◽  
pp. 113-116
Author(s):  
L A Bagdasaryan ◽  
I E Korneyeva

The aim of the study is to systematically analyze the data available in the modern literature on the relationship between endometrial thickness and the frequency of pregnancy in the program of assisted reproductive technologies (ART). Materials and methods. The review includes data from foreign and domestic articles found in PubMed on this topic. Results. The article presents data on the relationship between the thickness of the endometrium and the frequency of pregnancy in ART programs. The greatest number of studies is devoted to the evaluation of the relationship between the thickness of the endometrium and the frequency of pregnancy on the day of the ovulation trigger. Data are presented on the existence of a correlation between the thickness of the endometrium measured on the day of the ovulation trigger and the frequency of clinical pregnancy, as well as data on the need to evaluate the structure of the endometrium and the state of subendometric blood flow. The importance of multilayered (three-layered) endometrium as a prognostic marker of success in in vitro fertilization/intracytoplasmic sperm injection programs in the ovum is emphasized. The conclusion. The thickness of the endometrium can not be used as an argument for canceling the cycle or abolishing embryo transfer to the uterine cavity. Further studies in this direction are needed with a study of the morphological and molecular genetic characteristics of the endometrium, which in the future will allow us to evaluate the relationship between the thickness of the endometrium and the probability of pregnancy.


Author(s):  
N.A. Altinnik , S.S. Zenin , V.V. Komarova et all

The article discusses the factors that determine the content of the legal limitations of pre-implantation genetic diagnosis in the framework of the in vitro fertilization procedure, taking into account international experience and modern domestic regulatory legal regulation of the field of assisted reproductive technologies. The authors substantiates the conclusion that it is necessary to legislate a list of medical indications for preimplantation genetic diagnosis, as well as the categories of hereditary or other genetic diseases diagnosed in the framework of this procedure.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sandra Monfort ◽  
Carmen Orellana ◽  
Silvestre Oltra ◽  
Mónica Rosello ◽  
Alfonso Caro-Llopis ◽  
...  

AbstractDevelopment of assisted reproductive technologies to address infertility has favored the birth of many children in the last years. The majority of children born with these treatments are healthy, but some concerns remain on the safety of these medical procedures. We have retrospectively analyzed both the fertilization method and the microarray results in all those children born between 2010 and 2019 with multiple congenital anomalies, developmental delay and/or autistic spectrum disorder (n = 486) referred for array study in our center. This analysis showed a significant excess of pathogenic copy number variants among those patients conceived after in vitro fertilization with donor oocyte with respect to those patients conceived by natural fertilization (p = 0.0001). On the other hand, no significant excess of pathogenic copy number variants was observed among patients born by autologous oocyte in vitro fertilization. Further studies are necessary to confirm these results and in order to identify the factors that may contribute to an increased risk of genomic rearrangements, as well as consider the screening for genomic alterations after oocyte donation in prenatal diagnosis.


2021 ◽  
pp. medhum-2020-011864
Author(s):  
Lisa Guntram

Uterus transplantation combined with in vitro fertilisation (IVF) (henceforth called UTx-IVF) as a treatment for infertility caused by an absence or malfunction of the uterus is advancing. About 50 transplantations have been conducted worldwide and at least 14 children have been born—9 of them by women taking part in a Swedish research project on UTx-IVF. The Swedish research protocol initially stated that the potential recipient must ‘have her own donor’ who is preferably related to the recipient. But what does it mean to ask someone for a uterus? What challenges does this question instigate? And what norms may it enact? In this article, I explore how 10 women—who have considered, and sometimes pursued, UTx-IVF—describe their experiences of searching for a donor. I aim to show how an analysis of such accounts can help us unpack some of the specific relational and gendered dimensions of UTx-IVF and by doing so enrich discussions of risks, benefits, care and support in UTx-IVF. Drawing on research in social sciences and medical humanities that has demonstrated how assisted reproductive technologies and organ donation can provoke social and familial conundrums, with respect to such topics as embodiment and identity, I present three patterns that describe different dimensions of the interviewees’ quest for a uterus donor. I discuss the negotiations that took place, how expectations unfolded and how entanglements were managed as the interviewees considered asking someone for a donation. Such an examination, I suggest, contributes to make care and support more attuned to the experiences and entanglements that UTx-IVF entails for those pursuing it. This will become increasingly important if (or when) UTx-IVF becomes part of general healthcare. To conclude, I problematise responsibilities and relational challenges in medical innovation, and in this way provide insights into how the ethical debate over UTx-IVF can broaden its scope.


Zygote ◽  
2021 ◽  
pp. 1-5
Author(s):  
Shiori Ashibe ◽  
Kanade Irisawa ◽  
Ken Yokawa ◽  
Yoshikazu Nagao

Summary Hyaluronidase is widely used in animal and human assisted reproductive technologies (ARTs) to remove cumulus cells around oocytes. However, adverse effects of hyaluronidase treatment, such as increased rates of degeneration and parthenogenesis, have been found after treatment of human and mouse oocytes. Currently, the mechanism(s) of the detrimental effects are unclear. The present study was initiated to identify the mechanism of adverse responses to hyaluronidase treatment in bovine oocytes and early embryos. Cumulus cells were removed from cumulus–oocyte complexes (COCs) with or without hyaluronidase and the oocytes were subjected to intracytoplasmic sperm injection (ICSI) or in vitro fertilization (IVF). Significantly lower rates of blastocyst formation were obtained in the hyaluronidase treatment group after ICSI (22.4%) and IVF (21.2%) compared with the non-hyaluronidase control groups: 36.1% after ICSI and 30.4% after IVF. Next, we examined the effect of hyaluronidase on parthenogenetic development rates and on the cytoplasmic levels of free calcium ions (Ca2+), reactive oxygen species (ROS) and reduced glutathione (GSH). No differences in parthenogenesis rates were found between treated and untreated groups. Ca2+ levels in oocytes from the hyaluronidase treatment group indicated using mean fluorescence intensity were significantly higher (68.8 ± 5.3) compared with in the control group (45.0 ± 2.5). No differences were found in the levels of ROS or GSH between the treated and untreated groups. We conclude that hyaluronidase might trigger an increase in Ca2+ levels in oocytes, resulting in a decreased potential for normal embryonic development.


2021 ◽  
Vol 10 (12) ◽  
pp. 2687
Author(s):  
Kaan Aydos ◽  
Oya Sena Aydos

Retrieving spermatozoa from the testicles has been a great hope for patients with non-obstructive azoospermia (NOA), but relevant methods have not yet been developed to the level necessary to provide resolutions for all cases of NOA. Although performing testicular sperm extraction under microscopic magnification has increased sperm retrieval rates, in vitro selection and processing of quality sperm plays an essential role in the success of in vitro fertilization. Moreover, sperm cryopreservation is widely used in assisted reproductive technologies, whether for therapeutic purposes or for future fertility preservation. In recent years, there have been new developments using advanced technologies to freeze and preserve even very small numbers of sperm for which conventional techniques are inadequate. The present review provides an up-to-date summary of current strategies for maximizing sperm recovery from surgically obtained testicular samples and, as an extension, optimization of in vitro sperm processing techniques in the management of NOA.


Zygote ◽  
2020 ◽  
Vol 28 (2) ◽  
pp. 154-159
Author(s):  
Juliana I. Candelaria ◽  
Anna C. Denicol

SummaryPreantral follicles are a potential reservoir of oocytes to be used in assisted reproductive technologies. With the increasing interest in developing techniques to grow preantral follicles in vitro, and as the bovine emerges as an appropriate model species to understand human folliculogenesis, the establishment of an accurate classification of developmental stages is needed. Classification of bovine preantral follicles has been mostly based on histological analysis and estimation models, which may not translate well to correctly characterize preantral follicles isolated from the ovary. In this study, we classified bovine preantral follicles by morphology upon isolation, determined diameter and number of granulosa cells by direct counting, and compared our results with previous studies reporting bovine preantral follicle classification. Follicles were isolated via homogenization of ovary tissue and classified into primary, early secondary and secondary stage based on morphology and number of layers of granulosa cells. Diameter was individually measured and Hoechst 33342 was used as a nuclear stain to count granulosa cells. We found that follicles classified by morphology into primary, early secondary, and secondary had different mean diameter and cell number (P < 0.01); cell number and diameter were positively correlated, as were cell density and cell number in each developmental stage (P < 0.01). Results obtained here were mostly in agreement with previous classifications based on histological sections and on isolated follicles, with some discrepancies. The present data add accuracy to classification of bovine preantral follicles that is critical to optimize culture conditions to produce developmentally competent oocytes.


Author(s):  
Nikolai A. Ognerubov

In connection with the active development and use of assisted reproductive technologies, protection of the human embryo and its legal status issue is currently being actualized. We make an attempt to reveal and explain some of the international aspects of the criminal law protection of the life and rights of the embryo. We consider the concept of “embryo” not only from the point of view of various scientific approaches (medicine, biology, embryology, jurisprudence), but also from the legislative side. We present and analyze the first mention of the embryo in Roman private law in connection with modern domestic law. We carry out an analysis of international legal acts that provide protection of embryos both “in vitro” and “in vivo”, followed by consideration of specific criminal law norms of foreign countries, namely Brazil and Colombia. We pay attention to some of the most famous cases from the jurisprudence of the European Court of Human Rights in order to understand the applied international legal acts “de facto”. The study also takes into account modern domestic legislation and considers point “g” of part 2 of Article 105 of the Criminal Code of the Russian Federation.


Sign in / Sign up

Export Citation Format

Share Document