Search results for " cryopreservation"
showing 10 items of 26 documents
Innovations in assisted reproductive technologies: impact on contemporary donor egg practice and future advances.
2018
Innovations in assisted reproductive technologies (ART) have driven progress in the donor egg field since the birth of the first baby derived from a donor egg in 1983. Over time, donor oocytes have become an increasingly used option for patients unable to conceive with autologous oocytes. In donor egg, the unique separation of the oocyte source and recipient uterus has created a model that has propelled advances in ART. Progressive ART innovations that have optimized the oocyte donor and resulting embryo include the following: evaluation of ovarian reserve, controlled ovarian hyperstimulation regimens that reduce the risk of ovarian hyperstimulation syndrome, blastocyst culture, oocyte cryo…
Randomized controlled trial comparing embryo culture in two incubator systems: G185 K-System versus EmbryoScope
2017
Objective To study whether the closed culture system, as compared with a benchtop incubator with similar culture conditions, has a positive impact on intracytoplasmic sperm injection (ICSI) outcomes. Design Randomized controlled trial. Setting University hospital. Patient(s) A total of 386 patients undergoing ICSI cycles with at least six mature oocytes were randomized. Intervention(s) Of these patients, 195 were assigned to the group with culture in a time-lapse imaging (TLI) system (EmbryoScope) and 191 to the group with culture in the G185 K-System (G185). Main Outcome Measure(s) Rate of implantation (primary endpoint) and embryo morphology grade. Result(s) No significant differences wer…
Theory about the Embryo Cryo‐Treatment
2017
Background To create hypothesis, which can give a logical explanation related to the benefits of freezing/thawing embryos. Cryopreservation is not only a technology used for storing embryos, but also a method of embryo treatment that can potentially improve the success rate in infertile couples. Methods From the analysis of multiple results in assisted reproductive technology, which have no satisfactory explanation to date, we found evidence to support a ‘therapeutic’ effect of the freezing/thawing of embryos on the process of recovery of the embryo and its subsequent implantation. Results Freezing/thawing is a way to activate the endogenous survival and repair responses in preimplantation …
Cryopreservation and autotransplantation of human ovarian tissue prior to cytotoxic therapy – A technique in its infancy but already successful in fe…
2008
Increasing survival rates in young cancer patients, new reproductive techniques and the growing interest in quality of life after gonadotoxic cancer therapies have placed fertility preservation as an important issue to oncologists, fertility specialists and patients. Several techniques are now available for fertility preservation in these patients. A new promising method is cryopreservation and transplantation of ovarian cortex. Ovarian tissue can be extracted by laparoscopy without any significant delay of gonadotoxic therapy. The tissue can be cryopreserved by specialised centres of reproductive medicine and transplanted in case the women experience premature ovarian failure (POF). This r…
New options in assisted reproduction technology: the Cryotop method of oocyte vitrification
2008
The Cryotop vitrification method has been shown to be a very useful tool for oocyte cryopreservation, giving excellent results regarding survival and clinical outcome. There are several clinical situations in which oocyte cryopreservation provides solutions that have not been available to date. This report describes three of these situations: (i) a low-responder patient who needed a single gene diagnosis due to the presence of a genetic disease; (ii) a patient undergoing endometrial bleeding on the day of oocyte retrieval who was also affected by a genetic disorder; and (iii) a patient who failed to become pregnant after the donation of vitrified oocytes and subsequently had the re-vitrifie…
Twins born after transplantation of ovarian cortical tissue and oocyte vitrification
2009
Objective To present a combination of ovarian tissue and oocyte cryopreservation as an effective strategy for achieving pregnancy in a breast cancer patient. Design Case report. Setting Tertiary care university-affiliated hospital, tissue bank, and infertility clinic. Patient(s) A 36-year-old patient diagnosed with atypical medullar breast cancer and negative for estrogen, P, and HER2 receptors underwent ovarian tissue cryopreservation before receiving chemotherapy and radiotherapy. Intervention(s) Laparoscopic ovarian cortex extraction, ovarian tissue cryopreservation, ovarian tissue thawing and transplantation, controlled ovarian stimulation (COS), oocyte retrieval, vitrification and IVF,…
Timing of cell division in human cleavage-stage embryos is linked with blastocyst formation and quality
2012
Noninvasive markers of embryo quality are being sought to improve IVF success. The present study aimed to discover possible associations between embryo division kinetics in the cleavage stage, the subsequent ability of human embryos to reach the blastocyst stage and the resulting blastocyst morphology. A retrospective cohort study analysed 834 embryos from 165 oocyte donation couples using a time-lapse monitoring system that allowed the recording of the exact timings for key events related to embryo development. Timing parameters were categorized into four quartiles. The probability of an embryo developing to a blastocyst was linked to a strict chronology of development. To further evaluate…
Improving ovarian tissue cryopreservation for oncologic patients: slow freezing versus vitrification, effect of different procedures and devices.
2013
Objective To compare slow freezing (SF) with four vitrification techniques (VT) for cryopreservation of ovarian tissue (OT) and to evaluate the best protocol for human OT in a xenograft model. Design Experimental study. Setting University hospital. Patient(s) Patients undergoing fertility preservation. Animal(s) Ovariectomized nude mice. Intervention(s) Cryopreservation of bovine OT after SF and four VTs (VT1, VT2, VT3, and VT4) by combining two cryoprotectant vitrification solutions (VS1 and VS2) and two devices (metallic grid and ethyl vinyl acetate bag), after which the cryopreservation of human OT by SF and VT1 and xenograft into nude mice. Main Outcome Measure(s) Follicular densities, …
Oocyte insemination techniques are related to alterations of embryo developmental timing in an oocyte donation model
2013
Because of the different intrinsic characteristics of the classic IVF and intracytoplasmic sperm injection (ICSI) techniques, the timing of zygote development can be influenced by the method of fertilization. However, there is no information about the relevance of the insemination procedure on embryo-quality parameters as measured through their developmental dynamics. The aim of this work was to determine if the insemination technique, IVF or ICSI, influences embryo developmental kinetics by examining 1203 embryos from 178 couples undergoing oocyte donation with IVF or ICSI. Using time-lapse information, this work calculated several developmental kinetic variables, from pronuclear fading (P…
Comparison of concomitant outcome achieved with fresh and cryopreserved donor oocytes vitrified by the Cryotop method
2008
Objective To evaluate the outcome of oocyte vitrification using the Cryotop method, observed in an egg donation program by simultaneously evaluating embryos derived from vitrified and fresh oocytes coming from the same stimulated cycle. Design Cohort prospective randomized study. Setting Instituto Valenciano de Infertilidad (IVI) Valencia, Spain. Patient(s) Thirty oocyte donors and 30 recipients with informed consents. Intervention(s) Vitrification by the Cryotop method. Warming 1 hour after vitrification. Microinjection of surviving MII and fresh oocytes, evaluation of fertilization, embryo development, and clinical results. Main Outcome Measure(s) Survival, fertilization, and cleavage rat…