Human oocyte cryopreservation: past, present and future

Koutlaki, N; Schoepper, Beate; Maroulis, Georgios; Diedrich, K.; Al‐Hasani, S.

doi:10.1016/s1472-6483(10)61449-6

Cited by 40 publications

(33 citation statements)

References 102 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…slow-cooling (74)) is the predominant method in practice for human oocyte cryopreservation (15). Despite approximately twenty years of effort, the results from this approach remain highly variable (cf.…”

Section: Discussionmentioning

confidence: 99%

“…Following successful reports in the mid-1990s (11)(12)(13)(14), an equilibrium freezing method using propylene glycol (PG) as the penetrating cryoprotective agent (CPA) has become the most utilized method to freeze human oocytes (15). Fabbri and colleagues (16) demonstrated a significant improvement in survival when the concentration of sucrose in the freezing medium was increased to 0.3 mol/L; reports of live births using this method or slight variations followed (17)(18)(19)(20)(21).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Human oocyte vitrification: the permeability of metaphase II oocytes to water and ethylene glycol and the appliance toward vitrification

Mullen

Mei

et al. 2008

Fertility and Sterility

View full text Add to dashboard Cite

Objectives-To determine the permeability of human metaphase II oocytes to ethylene glycol and water in the presence of ethylene glycol, and to use this information to develop a method to vitrify human oocytes.Design-An incomplete randomized block design was used for this study.Setting-A University-affiliated assisted reproductive center.Patients-Women undergoing assisted reproduction in the Center for Reproductive Medicine at Shandong University.Interventions-Oocytes were exposed to 1.0 molar ethylene glycol in a single step, and photographed during subsequent volume excursions.Main outcome measures-A 2-parameter model was employed to estimate the permeability to water and EG.Results-Water permeability ranged from 0.15 to 1.17 µm/(min·atm), and ethylene glycol permeability ranged from 1.5 to 30 µm/min between 7 °C at 36 °C. The activation energies for water and ethylene glycol permeability were 14.42 Kcal/mol and 21.20 Kcal/mol, respectively. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.Some of the results from this study were presented at the 62 nd annual meeting of the American Society for Reproductive Medicine, 21-25 October 2006, in New Orleans, LA USA. Conflict of Interest: None. CapsuleHuman metaphase II oocyte permeability to ethylene glycol was determined. A method for vitrification, based upon fundamental principles, was developed from these data. Conclusions-Despite the lower permeability of human MII oocytes to ethylene glycol compared to previously published values for propylene glycol and dimethylsulfoxide, methods to add and remove human oocytes with a vitrifiable concentration of ethylene glycol can be designed which prevent excessive osmotic stress and minimize exposure to high concentrations of this compound. NIH Public Access

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Human oocyte vitrification: the permeability of metaphase II oocytes to water and ethylene glycol and the appliance toward vitrification

Mullen

Mei

et al. 2008

Fertility and Sterility

View full text Add to dashboard Cite

show abstract

“…During the last decade, considerable progress has been made in the development of protocols for cryopreservation of mature oocytes, as evidenced by improved survival and increased implantation rates of embryos derived from such thawed oocytes (reviewed by [1][2][3]). However, there are compelling and practical applications for freezing immature oocytes including the preservation of fertility for cancer patients when chemotherapy must proceed within a short timeline, the contra-indication of ovarian stimulation (due to hormone-sensitive tumors), and the lack of a male partner.…”

Section: Introductionmentioning

confidence: 99%

“…Cryopreservation of immature oocytes may also prove beneficial during routine ART, notably in combination with IVM for patients at risk of ovarian hyperstimulation syndrome. Moreover, the use of immature oocytes for cryopreservation may circumvent some of the limitations associated with the cooling/warming of mature oocytes, specifically relating to the functional integrity of the meiotic spindle and ploidy of resulting embryos (reviewed by [2,4,5]). …”

Section: Introductionmentioning

confidence: 99%

Maturation outcomes are improved following Cryoleaf vitrification of immature human oocytes when compared to choline-based slow-freezing

Combelles

Ceyhan

Wang

et al. 2011

J Assist Reprod Genet

View full text Add to dashboard Cite

Purpose The cryopreservation of immature oocytes permits oocyte banking for patients at risk of losing their fertility. However, the optimum protocol for such fertility preservation remains uncertain. Methods The present study investigated the survival, maturation, cytoskeletal and chromosome organization of sibling immature oocytes leftover from controlled ovarian stimulation cycles, that were either slow-frozen (with choline-substitution) or vitrified. A comparison group included oocytes that were never cryopreserved. Results Among the three groups, comparable rates were observed for both survival (67-70%) and polar body extrusion (59-79%). Significantly more oocytes underwent spontaneous activation after IVM following slow-freezing compared with either vitrification or no cryopreservation. Likewise, the incidence of spindle abnormalities was greatest in the slow-frozen group, with no differences in spindle morphometrics or chromosome organization.Conclusions While the overall incidence of mature oocytes with normal bipolar spindles from warmed immature oocytes was low, the yield using Cryoleaf vitrification was slightly superior to choline-based slow-freezing.

show abstract

“…It is anticipated that some infertile women may have no choice but to use imported cryopreserved oocytes instead of freshlyretrieved oocytes, due to the shortage of oocyte donors in their locality, which in turn gives rise to new ethical issues. In particular, it must be noted that although oocyte cryopreservation technology has made rapid strides in the past few years, the technology is still sub-optimal, and all studies have consistently shown that the chances of conception are always lower with cryopreserved oocytes compared to freshly-retrieved oocytes [17,18]. Given the high costs of clinically assisted reproduction with imported cryopreserved oocytes, the patient must rightfully be informed of this fact through professional counseling.…”

mentioning

confidence: 99%

Legal and ethical issues in the international transaction of donor sperm and eggs

Heng

2007

J Assist Reprod Genet

View full text Add to dashboard Cite

Pertinent ethical and legal issues in the international transaction of donor sperm and eggs are discussed. Firstly, there may be legislative and ethical "contradiction" by the local health authority in permitting import of donor gametes, due to varying policies on donor reimbursement in different countries. This is particularly significant in countries where the underlying principle of gamete donation is altruistic motivation, and where reimbursement is given only for direct "out-of-pocket" expenses i.e. traveling costs. Secondly, there is a lack of clear and coherent internationallybinding legislation and regulatory guidelines overseeing the exchange of donor gametes across international borders. In particular, provisions should be made for donor traceability if gametes are sourced from abroad. Thirdly, in the case of "frozen-egg donation" from abroad, patients must rightfully be informed that current cryopreservation technology is still sub-optimal, and all studies have consistently shown that the chances of conception are always lower with "frozen-eggs" compared to freshly-retrieved eggs. Finally, regulatory safeguards should be put in place to prevent fertility clinics and medical professionals from "re-selling" imported donor gametes at a profit to the patient, since it would be thoroughly unprofessional for them to earn a profit simply through the 'brokerage' of donated human material.Keywords Eggs . Ethics . Export . Gametes . Import . Legal . Sperm Recent years have seen an increasing transaction of donor sperm and oocytes across international borders [1, 2], con-

show abstract

Human oocyte cryopreservation: past, present and future

Cited by 40 publications

References 102 publications

Human oocyte vitrification: the permeability of metaphase II oocytes to water and ethylene glycol and the appliance toward vitrification

Human oocyte vitrification: the permeability of metaphase II oocytes to water and ethylene glycol and the appliance toward vitrification

Maturation outcomes are improved following Cryoleaf vitrification of immature human oocytes when compared to choline-based slow-freezing

Legal and ethical issues in the international transaction of donor sperm and eggs

Contact Info

Product

Resources

About