The Experts below are selected from a list of 16107 Experts worldwide ranked by ideXlab platform
Mariemadeleine Dolmans - One of the best experts on this subject based on the ideXlab platform.
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successful Vitrification and autografting of baboon papio anubis ovarian tissue
2013Co-Authors: Christiani Andrade Amorim, Mariemadeleine Dolmans, Jacques Donnez, Jonathan Jaeger, Julie Vanacker, Sophie Jacobs, Ram V Devireddy, Anne Van Langendonckt, Valerie LuyckxAbstract:STUDY QUESTION: Can a Vitrification protocol using an ethylene glycol/dimethyl sulphoxide-based solution and a cryopin successfully cryopreserve baboon ovarian tissue? SUMMARY ANSWER: Our results show that baboon ovarian tissue can be successfully cryopreserved with our Vitrification protocol. WHAT IS KNOWN ALREADY: Non-human primates have already been used as an animal model to test Vitrification protocols for human ovarian tissue cryopreservation. STUDY DESIGN, SIZE, DURATION: Ovarian biopsies from five adult baboons were vitrified, warmed and autografted for 5 months. PARTICIPANTS/MATERIALS, SETTING, METHODS: After grafting, follicle survival, growth and function and also the quality of stromal tissue were assessed histologically and by immunohistochemistry. The influence of the Vitrification procedure on the cooling rate was evaluated by a computer model. MAIN RESULTS: After Vitrification, warming and long-term grafting, follicles were able to grow and maintain their function, as illustrated by Ki67, anti-Mullerian hormone (AMH) and growth differentiation factor-9 (GDF-9) immunostaining. Corpora lutea were also observed, evidencing successful ovulation in all the animals. Stromal tissue quality did not appear to be negatively affected by our cryopreservation procedure, as demonstrated by vascularization and proportions of fibrotic areas, which were similar to those found in fresh ungrafted ovarian tissue. LIMITATIONS, REASONS FOR CAUTION: Despite our promising findings, before applying this technique in a clinical setting, we need to validate it by achieving pregnancies. WIDER IMPLICATIONS OF THE FINDINGS: In addition to encouraging results obtained with our Vitrification procedure for non-human ovarian tissue, this study also showed, for the first time, expression of AMH and GDF-9 in ovarian follicles.
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Vitrification and xenografting of human ovarian tissue
2012Co-Authors: Christiani Andrade Amorim, Mariemadeleine Dolmans, Jacques Donnez, Anu David, Jonathan Jaeger, Julie Vanacker, Alessandra Camboni, Anne Van LangendoncktAbstract:OBJECTIVE: To assess the efficiency of two Vitrification protocols to cryopreserve human preantral follicles with the use of a xenografting model. DESIGN: Pilot study. SETTING: Gynecology research unit in a university hospital. PATIENT(S): Ovarian biopsies were obtained from seven women aged 30-41 years. INTERVENTION(S): Ovarian tissue fragments were subjected to one of three cryopreservation protocols (slow freezing, Vitrification protocol 1, and Vitrification protocol 2) and xenografted for 1 week to nude mice. MAIN OUTCOME MEASURE(S): The number of morphologically normal follicles after cryopreservation and grafting and fibrotic surface area were determined by histologic analysis. Apoptosis was assessed by the TUNEL method. Morphometric analysis of TUNEL-positive surface area also was performed. Follicle proliferation was evaluated by immunohistochemistry. RESULT(S): After xenografting, a difference was observed between the cryopreservation procedures applied. According to TUNEL analysis, both Vitrification protocols showed better preservation of preantral follicles than the conventional freezing method. Moreover, histologic evaluation showed a significantly higher proportion of primordial follicles in vitrified (protocol 2)-warmed ovarian tissue than in frozen-thawed tissue. The proportion of growing follicles and fibrotic surface area was similar in all groups. CONCLUSION(S): Vitrification procedures appeared to preserve not only the morphology and survival of preantral follicles after 1 week of xenografting, but also their ability to resume folliculogenesis. In addition, Vitrification protocol 2 had a positive impact on the quiescent state of primordial follicles after xenografting.
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Vitrification as an alternative means of cryopreserving ovarian tissue
2011Co-Authors: Christiani Andrade Amorim, Mara Curaba, Anne Van Langendonckt, Mariemadeleine Dolmans, Jacques DonnezAbstract:Because of the simplicity of Vitrification, many authors have investigated it as an alternative to slow freezing for cryopreserving ovarian tissue. In the last decade, numerous studies have evaluated Vitrification of ovarian tissue from both humans and animals.Different Vitrification solutions and protocols, mostly adapted from embryo and oocyte Vitrification, have been applied. The results have been discrepant from species to species and even within the same species, but lately they appear to indicate that Vitrification can achieve similar or even superior results to conventional freezing. Despite the encouraging results obtained with Vitrification of ovarian tissue from humans and different animal species, it is necessary to understand how Vitrification solutions and protocols can affect ovarian tissue, notably preantral follicles. In addition, it is important to bear in mind that the utilization of different approaches to assess tissue functionality and oocyte quality is essential in order to validate the promising results already obtained with Vitrification procedures. This review summarizes the principles of Vitrification, discusses the advantages of Vitrification protocols for ovarian tissue cryopreservation and describes different studies conducted on the Vitrification of ovarian tissue in humans and animal species.
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Vitrification of human ovarian tissue effect of different solutions and procedures
2011Co-Authors: Christiani Andrade Amorim, Anne Van Langendonckt, Mariemadeleine Dolmans, Anu David, Jacques DonnezAbstract:OBJECTIVE: To test the effect of different Vitrification solutions and procedures on the morphology of human preantral follicles. DESIGN: Pilot study. SETTING: Gynecology research unit in a university hospital. PATIENT(S): Ovarian biopsies were obtained from nine women aged 22-35 years. INTERVENTION(S): Ovarian tissue fragments were subjected to [1] different Vitrification solutions to test their toxicity or [2] different Vitrification methods using plastic straws, medium droplets, or solid-surface Vitrification before in vitro culture. MAIN OUTCOME MEASURE(S): Number of morphologically normal follicles after toxicity testing or Vitrification with the different treatments determined by histologic analysis. RESULT(S): In the toxicity tests, only VS3 showed similar results to fresh tissue before and after in vitro culture (fresh controls 1 and 2). In addition, this was the only solution able to completely vitrify. In all Vitrification procedures, the percentage of normal follicles was lower than in controls. However, of the three protocols, the droplet method yielded a significantly higher proportion of normal follicles. CONCLUSION(S): Our experiments showed VS3 to have no deleterious effect on follicular morphology and to be able to completely vitrify, although Vitrification procedures were found to affect human follicles. Nevertheless, the droplet method resulted in a higher percentage of morphologically normal follicles.
Jacques Donnez - One of the best experts on this subject based on the ideXlab platform.
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successful Vitrification and autografting of baboon papio anubis ovarian tissue
2013Co-Authors: Christiani Andrade Amorim, Mariemadeleine Dolmans, Jacques Donnez, Jonathan Jaeger, Julie Vanacker, Sophie Jacobs, Ram V Devireddy, Anne Van Langendonckt, Valerie LuyckxAbstract:STUDY QUESTION: Can a Vitrification protocol using an ethylene glycol/dimethyl sulphoxide-based solution and a cryopin successfully cryopreserve baboon ovarian tissue? SUMMARY ANSWER: Our results show that baboon ovarian tissue can be successfully cryopreserved with our Vitrification protocol. WHAT IS KNOWN ALREADY: Non-human primates have already been used as an animal model to test Vitrification protocols for human ovarian tissue cryopreservation. STUDY DESIGN, SIZE, DURATION: Ovarian biopsies from five adult baboons were vitrified, warmed and autografted for 5 months. PARTICIPANTS/MATERIALS, SETTING, METHODS: After grafting, follicle survival, growth and function and also the quality of stromal tissue were assessed histologically and by immunohistochemistry. The influence of the Vitrification procedure on the cooling rate was evaluated by a computer model. MAIN RESULTS: After Vitrification, warming and long-term grafting, follicles were able to grow and maintain their function, as illustrated by Ki67, anti-Mullerian hormone (AMH) and growth differentiation factor-9 (GDF-9) immunostaining. Corpora lutea were also observed, evidencing successful ovulation in all the animals. Stromal tissue quality did not appear to be negatively affected by our cryopreservation procedure, as demonstrated by vascularization and proportions of fibrotic areas, which were similar to those found in fresh ungrafted ovarian tissue. LIMITATIONS, REASONS FOR CAUTION: Despite our promising findings, before applying this technique in a clinical setting, we need to validate it by achieving pregnancies. WIDER IMPLICATIONS OF THE FINDINGS: In addition to encouraging results obtained with our Vitrification procedure for non-human ovarian tissue, this study also showed, for the first time, expression of AMH and GDF-9 in ovarian follicles.
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Vitrification and xenografting of human ovarian tissue
2012Co-Authors: Christiani Andrade Amorim, Mariemadeleine Dolmans, Jacques Donnez, Anu David, Jonathan Jaeger, Julie Vanacker, Alessandra Camboni, Anne Van LangendoncktAbstract:OBJECTIVE: To assess the efficiency of two Vitrification protocols to cryopreserve human preantral follicles with the use of a xenografting model. DESIGN: Pilot study. SETTING: Gynecology research unit in a university hospital. PATIENT(S): Ovarian biopsies were obtained from seven women aged 30-41 years. INTERVENTION(S): Ovarian tissue fragments were subjected to one of three cryopreservation protocols (slow freezing, Vitrification protocol 1, and Vitrification protocol 2) and xenografted for 1 week to nude mice. MAIN OUTCOME MEASURE(S): The number of morphologically normal follicles after cryopreservation and grafting and fibrotic surface area were determined by histologic analysis. Apoptosis was assessed by the TUNEL method. Morphometric analysis of TUNEL-positive surface area also was performed. Follicle proliferation was evaluated by immunohistochemistry. RESULT(S): After xenografting, a difference was observed between the cryopreservation procedures applied. According to TUNEL analysis, both Vitrification protocols showed better preservation of preantral follicles than the conventional freezing method. Moreover, histologic evaluation showed a significantly higher proportion of primordial follicles in vitrified (protocol 2)-warmed ovarian tissue than in frozen-thawed tissue. The proportion of growing follicles and fibrotic surface area was similar in all groups. CONCLUSION(S): Vitrification procedures appeared to preserve not only the morphology and survival of preantral follicles after 1 week of xenografting, but also their ability to resume folliculogenesis. In addition, Vitrification protocol 2 had a positive impact on the quiescent state of primordial follicles after xenografting.
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Vitrification as an alternative means of cryopreserving ovarian tissue
2011Co-Authors: Christiani Andrade Amorim, Mara Curaba, Anne Van Langendonckt, Mariemadeleine Dolmans, Jacques DonnezAbstract:Because of the simplicity of Vitrification, many authors have investigated it as an alternative to slow freezing for cryopreserving ovarian tissue. In the last decade, numerous studies have evaluated Vitrification of ovarian tissue from both humans and animals.Different Vitrification solutions and protocols, mostly adapted from embryo and oocyte Vitrification, have been applied. The results have been discrepant from species to species and even within the same species, but lately they appear to indicate that Vitrification can achieve similar or even superior results to conventional freezing. Despite the encouraging results obtained with Vitrification of ovarian tissue from humans and different animal species, it is necessary to understand how Vitrification solutions and protocols can affect ovarian tissue, notably preantral follicles. In addition, it is important to bear in mind that the utilization of different approaches to assess tissue functionality and oocyte quality is essential in order to validate the promising results already obtained with Vitrification procedures. This review summarizes the principles of Vitrification, discusses the advantages of Vitrification protocols for ovarian tissue cryopreservation and describes different studies conducted on the Vitrification of ovarian tissue in humans and animal species.
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Vitrification of human ovarian tissue effect of different solutions and procedures
2011Co-Authors: Christiani Andrade Amorim, Anne Van Langendonckt, Mariemadeleine Dolmans, Anu David, Jacques DonnezAbstract:OBJECTIVE: To test the effect of different Vitrification solutions and procedures on the morphology of human preantral follicles. DESIGN: Pilot study. SETTING: Gynecology research unit in a university hospital. PATIENT(S): Ovarian biopsies were obtained from nine women aged 22-35 years. INTERVENTION(S): Ovarian tissue fragments were subjected to [1] different Vitrification solutions to test their toxicity or [2] different Vitrification methods using plastic straws, medium droplets, or solid-surface Vitrification before in vitro culture. MAIN OUTCOME MEASURE(S): Number of morphologically normal follicles after toxicity testing or Vitrification with the different treatments determined by histologic analysis. RESULT(S): In the toxicity tests, only VS3 showed similar results to fresh tissue before and after in vitro culture (fresh controls 1 and 2). In addition, this was the only solution able to completely vitrify. In all Vitrification procedures, the percentage of normal follicles was lower than in controls. However, of the three protocols, the droplet method yielded a significantly higher proportion of normal follicles. CONCLUSION(S): Our experiments showed VS3 to have no deleterious effect on follicular morphology and to be able to completely vitrify, although Vitrification procedures were found to affect human follicles. Nevertheless, the droplet method resulted in a higher percentage of morphologically normal follicles.
Debra A Gook - One of the best experts on this subject based on the ideXlab platform.
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a critical appraisal of cryopreservation slow cooling versus Vitrification of human oocytes and embryos
2012Co-Authors: David H Edgar, Debra A GookAbstract:results: Slow cooling is associated with lower survival rates and compromised development relative to Vitrification when applied to metaphase II (MII) oocytes, although the Vitrification results have predominantly been obtained using direct contact with liquid nitrogen and there is some evidence that optimal protocols for slow cooling of MII oocytes are yet to be established. There are no prospective ran- domized controlled trials (RCTs) which support the use of either technique with pronuclear oocytes although Vitrification has become the method of choice. Optimal slow cooling, using modifications of traditional methodology, and Vitrification can result in high survival rates of early embryos, which implant at the same rate as equivalent fresh counterparts. Many studies report high survival and implantation rates following Vitrification of blastocysts. Although slow cooling of blastocysts has been reported to be inferior in some studies, others comparing the two approaches in the same clinical setting have demonstrated comparable results. The variation in the extent of embryo selection applied in studies can lead to apparent differences in clinical efficiency, which may not be significant if expressed on a 'per oocyte used' basis. conclusions: Available evidence suggests that Vitrification is the current method of choice when cryopreserving MII oocytes. Early cleavage stage embryos can be cryopreserved with equal success using slow cooling and Vitrification. Successful blastocyst cryopreservation may be more consistently achieved with Vitrification but optimal slow cooling can produce similar results. There are key limitations associated with the available evidence base, including a paucity of RCTs, limited reporting of live birth outcomes and limited reporting of detail which would allow assessment of the impact of differences in female age. While Vitrification has a clear role in ART, we support continued research to establish optimal slow cooling methods which may assist in alleviating concerns over safety issues, such as storage, transport and the use of very high cryoprotectant concentrations.
Christiani Andrade Amorim - One of the best experts on this subject based on the ideXlab platform.
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successful Vitrification and autografting of baboon papio anubis ovarian tissue
2013Co-Authors: Christiani Andrade Amorim, Mariemadeleine Dolmans, Jacques Donnez, Jonathan Jaeger, Julie Vanacker, Sophie Jacobs, Ram V Devireddy, Anne Van Langendonckt, Valerie LuyckxAbstract:STUDY QUESTION: Can a Vitrification protocol using an ethylene glycol/dimethyl sulphoxide-based solution and a cryopin successfully cryopreserve baboon ovarian tissue? SUMMARY ANSWER: Our results show that baboon ovarian tissue can be successfully cryopreserved with our Vitrification protocol. WHAT IS KNOWN ALREADY: Non-human primates have already been used as an animal model to test Vitrification protocols for human ovarian tissue cryopreservation. STUDY DESIGN, SIZE, DURATION: Ovarian biopsies from five adult baboons were vitrified, warmed and autografted for 5 months. PARTICIPANTS/MATERIALS, SETTING, METHODS: After grafting, follicle survival, growth and function and also the quality of stromal tissue were assessed histologically and by immunohistochemistry. The influence of the Vitrification procedure on the cooling rate was evaluated by a computer model. MAIN RESULTS: After Vitrification, warming and long-term grafting, follicles were able to grow and maintain their function, as illustrated by Ki67, anti-Mullerian hormone (AMH) and growth differentiation factor-9 (GDF-9) immunostaining. Corpora lutea were also observed, evidencing successful ovulation in all the animals. Stromal tissue quality did not appear to be negatively affected by our cryopreservation procedure, as demonstrated by vascularization and proportions of fibrotic areas, which were similar to those found in fresh ungrafted ovarian tissue. LIMITATIONS, REASONS FOR CAUTION: Despite our promising findings, before applying this technique in a clinical setting, we need to validate it by achieving pregnancies. WIDER IMPLICATIONS OF THE FINDINGS: In addition to encouraging results obtained with our Vitrification procedure for non-human ovarian tissue, this study also showed, for the first time, expression of AMH and GDF-9 in ovarian follicles.
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Vitrification and xenografting of human ovarian tissue
2012Co-Authors: Christiani Andrade Amorim, Mariemadeleine Dolmans, Jacques Donnez, Anu David, Jonathan Jaeger, Julie Vanacker, Alessandra Camboni, Anne Van LangendoncktAbstract:OBJECTIVE: To assess the efficiency of two Vitrification protocols to cryopreserve human preantral follicles with the use of a xenografting model. DESIGN: Pilot study. SETTING: Gynecology research unit in a university hospital. PATIENT(S): Ovarian biopsies were obtained from seven women aged 30-41 years. INTERVENTION(S): Ovarian tissue fragments were subjected to one of three cryopreservation protocols (slow freezing, Vitrification protocol 1, and Vitrification protocol 2) and xenografted for 1 week to nude mice. MAIN OUTCOME MEASURE(S): The number of morphologically normal follicles after cryopreservation and grafting and fibrotic surface area were determined by histologic analysis. Apoptosis was assessed by the TUNEL method. Morphometric analysis of TUNEL-positive surface area also was performed. Follicle proliferation was evaluated by immunohistochemistry. RESULT(S): After xenografting, a difference was observed between the cryopreservation procedures applied. According to TUNEL analysis, both Vitrification protocols showed better preservation of preantral follicles than the conventional freezing method. Moreover, histologic evaluation showed a significantly higher proportion of primordial follicles in vitrified (protocol 2)-warmed ovarian tissue than in frozen-thawed tissue. The proportion of growing follicles and fibrotic surface area was similar in all groups. CONCLUSION(S): Vitrification procedures appeared to preserve not only the morphology and survival of preantral follicles after 1 week of xenografting, but also their ability to resume folliculogenesis. In addition, Vitrification protocol 2 had a positive impact on the quiescent state of primordial follicles after xenografting.
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Vitrification as an alternative means of cryopreserving ovarian tissue
2011Co-Authors: Christiani Andrade Amorim, Mara Curaba, Anne Van Langendonckt, Mariemadeleine Dolmans, Jacques DonnezAbstract:Because of the simplicity of Vitrification, many authors have investigated it as an alternative to slow freezing for cryopreserving ovarian tissue. In the last decade, numerous studies have evaluated Vitrification of ovarian tissue from both humans and animals.Different Vitrification solutions and protocols, mostly adapted from embryo and oocyte Vitrification, have been applied. The results have been discrepant from species to species and even within the same species, but lately they appear to indicate that Vitrification can achieve similar or even superior results to conventional freezing. Despite the encouraging results obtained with Vitrification of ovarian tissue from humans and different animal species, it is necessary to understand how Vitrification solutions and protocols can affect ovarian tissue, notably preantral follicles. In addition, it is important to bear in mind that the utilization of different approaches to assess tissue functionality and oocyte quality is essential in order to validate the promising results already obtained with Vitrification procedures. This review summarizes the principles of Vitrification, discusses the advantages of Vitrification protocols for ovarian tissue cryopreservation and describes different studies conducted on the Vitrification of ovarian tissue in humans and animal species.
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Vitrification of human ovarian tissue effect of different solutions and procedures
2011Co-Authors: Christiani Andrade Amorim, Anne Van Langendonckt, Mariemadeleine Dolmans, Anu David, Jacques DonnezAbstract:OBJECTIVE: To test the effect of different Vitrification solutions and procedures on the morphology of human preantral follicles. DESIGN: Pilot study. SETTING: Gynecology research unit in a university hospital. PATIENT(S): Ovarian biopsies were obtained from nine women aged 22-35 years. INTERVENTION(S): Ovarian tissue fragments were subjected to [1] different Vitrification solutions to test their toxicity or [2] different Vitrification methods using plastic straws, medium droplets, or solid-surface Vitrification before in vitro culture. MAIN OUTCOME MEASURE(S): Number of morphologically normal follicles after toxicity testing or Vitrification with the different treatments determined by histologic analysis. RESULT(S): In the toxicity tests, only VS3 showed similar results to fresh tissue before and after in vitro culture (fresh controls 1 and 2). In addition, this was the only solution able to completely vitrify. In all Vitrification procedures, the percentage of normal follicles was lower than in controls. However, of the three protocols, the droplet method yielded a significantly higher proportion of normal follicles. CONCLUSION(S): Our experiments showed VS3 to have no deleterious effect on follicular morphology and to be able to completely vitrify, although Vitrification procedures were found to affect human follicles. Nevertheless, the droplet method resulted in a higher percentage of morphologically normal follicles.
Yan Wang - One of the best experts on this subject based on the ideXlab platform.
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Vitrification versus slow freezing for human ovarian tissue cryopreservation a systematic review and meta anlaysis
2017Co-Authors: Qingquan Shi, Yidong Xie, Yan WangAbstract:Vitrification is a well-accepted procedure for cryopreservation of gametes and embryos. Less is known, however, about its performance in preserving ovarian tissue, for which slow freezing is the current convention. Increasing interest is being focused on Vitrification, but there are as yet no standard protocols for its use with ovarian tissue. In part, this is because of the variety of cell types and complex nature of ovarian tissue. We performed a meta-analysis of 14 studies that compared Vitrification with slow freezing for cryopreservation of ovarian tissue. In the pooled analysis, there was no significant difference between the two methods in terms of the proportion of intact primordial follicles, but Vitrification was associated with significantly less DNA damage. Secondary endpoints included the number of stromal cells, significantly higher with Vitrification, and primordial follicle density, which did not differ between the two methods. The present meta-analysis suggests that Vitrification may be more effective than slow freezing, with less primordial follicular DNA strand breaks and better preservation of stromal cells. These advantages should lead to improved ovarian function after transplantation.
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Novel needle immersed Vitrification: a practical and convenient method with potential advantages in mouse and human ovarian tissue cryopreservation
2008Co-Authors: Yan Wang, Zhun Xiao, Wei FanAbstract:BACKGROUND: Ovarian tissue cryopreservation may be a potential method of preserving fertility in women who have experienced gonadotoxic treatments. To improve the efficiency of existing cryopreservation, we developed a practical and convenient Vitrification method named needle immersed Vitrification (NIV), which required a less concentrated and minimum volume of Vitrification solution. METHODS: Mouse ovaries and human ovarian cortex fragments were vitrified using the NIV method, the slow-freezing method or the dropping Vitrification method. Their morphology, ultrastructure and viability were analyzed and compared with fresh group. RESULTS: Primordial follicles in human and mouse ovarian tissues vitrified by NIV were well preserved. In mice, the percentages of normal morphological primary and secondary follicles were greater in the NIV group than that in the slow-freezing group or dropping Vitrification group (P < 0.001). Ultrastructure of the stromal cells was preserved better in the NIV group than the slow-freezing or the dropping Vitrification group in both human (P = 0.039, P = 0.023, respectively) and mouse (both P < 0.001) models. The viability assessment on frozen-thawed human ovarian tissue strips revealed that the follicles and the stroma had a satisfactory viability in the NIV group. In mouse model, the ovarian functional restoration in the NIV group was the best among three freezing groups, which was demonstrated by follicle counting in grafts after transplantation (P = 0.009 and P = 0.010 versus slow freezing and dropping Vitrification, respectively). The cleavage rate of oocytes from grafts of the NIV group was most similar to that observed in the fresh group. CONCLUSIONS: The NIV method could facilitate Vitrification process, maximize the cooling rate and reduce the toxicity of the Vitrification solution with a minimal volume of less concentrated cryoprotectants. NIV was practical and convenient for cryopreservation of ovarian tissues.
