RESUMO
Some synthetic polymers can be used at low concentrations to reduce the toxicity of conventional cryoprotectant agents. In this study we investigated whether the addition of synthetic polymers to a conventional cryoprotectant solution would improve the cryopreservation of bovine ovarian tissue. Freshly collected ovaries from ten adult crossbred cows were incised using a scalpel in the frontal section. From each cow, ovarian cortical slices of 1 mm thickness were divided into 30 fragments of 3 × 3 mm, of which 10 served as fresh controls, 10 were vitrified with conventional cryoprotectant agents (2.93 M glycerol, 27 % w/v; 4.35 M ethylene glycol, 27 % w/v), and 10 were vitrified using the same cryoprotectant agents in addition to synthetic polymers (0.2 % PVP K-12, 0.2 % SuperCool X-1000 ™ w/v and 0.4 % SuperCool Z-1000 ™ w/v). After warming, histology was used to assess follicular quantity and integrity, while in vitro culture of mechanically isolated follicles encapsulated in an alginate matrix was performed for 15 days to assess their growth and hormonal production. Vitrified ovarian tissues presented abnormal morphology, a higher percentage of atretic follicles, and their isolated follicles had lower survival rates and lower frequency of antrum formation during in vitro culture compared to those from fresh tissue. At the end of culture, the follicles that had been cryopreserved produced less estradiol and progesterone than the fresh ones. The addition of synthetic polymers during tissue vitrification did not modify any of these parameters. We conclude that, under the conditions of this study, the use of this combination of synthetic polymers for tissue vitrification did not enhance the preservation of the morphological or functional integrity of bovine ovarian follicles.
RESUMO
Insulin-like growth factors (IGFs) are known for their involvement in endocrine and paracrine regulation of ovarian function. Although IGF2 is the predominant circulating and intraovarian form of IGFs in primate species, the stage-specific follicular expression, action, and regulation of IGF2 are not well defined. Therefore, experiments were conducted to investigate the follicular IGF production in response to steroid hormone regulation and the direct IGF actions on follicular development and function in vitro. Preantral follicles were isolated from rhesus macaque ovaries and cultured to the antral stage in media supplemented with follicle-stimulating hormone and insulin. Follicles were randomly assigned to treatment groups: (a) control, (b) trilostane (a steroid synthesis inhibitor), (c) trilostane + estradiol, (d) trilostane + progesterone, and (e) trilostane + dihydrotestosterone. Media was analyzed for IGF concentrations, which were correlated to follicle growth. Follicles produced IGF2, but not IGF1, at the antral stage. Steroid depletion decreased, whereas steroid replacement increased, IGF2 production by antral follicles. Media IGF2 levels correlated positively with antral follicle diameters. Macaque preantral follicles and granulosa cells were subsequently cultured without (control) and with recombinant human IGF2 supplementation. Follicle survival, growth, and paracrine factor production, as well as granulosa cell proliferation and gonadotropin receptor gene expression, were assessed. IGF2 addition increased follicle survival rates, diameters and inhibin B production, as well as granulosa cell proliferation. These data demonstrate that IGF2 produced by antral follicles, in response to steroid hormone regulation, could act as a paracrine factor that positively impacts preantral follicle development and function in primates.
Assuntos
Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like II/farmacologia , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/metabolismo , Animais , Relação Dose-Resposta a Droga , Estradiol/análogos & derivados , Estradiol/farmacologia , Feminino , Hormônio Foliculoestimulante/farmacologia , Fator de Crescimento Insulin-Like II/administração & dosagem , Macaca mulatta , Progesterona/farmacologia , Técnicas de Cultura de TecidosRESUMO
Access to assisted reproductive technology (ART) and fertility preservation remains restricted in middle and low income countries. We sought to review the status of ART and fertility preservation in Brazil, considering social indicators and legislative issues that may hinder the universal access to these services. Although the Brazilian Constitution expressly provides the right to health, and ordinary law ensures the state is obliged to support family planning, access to services related to ART and fertility preservation is neither easy nor egalitarian in Brazil. Only a handful of public hospitals provide free ART, and their capacity far from meets demand. Health insurance does not cover ART, and the cost of private care is unaffordable to most people. Brazilian law supports, but does not command, the state provision of ART and fertility preservation to guarantee the right to family planning; therefore, the availability of state-funded treatments is still scarce, reinforcing social disparities. Economic projections suggest that including ART in the Brazilian health system is affordable and may actually become profitable to the state in the long term, not to mention the ethical imperative of recognizing infertility as a disease, with no reason to be excluded from a health system that claims to be 'universal'.
Assuntos
Preservação da Fertilidade , Acessibilidade aos Serviços de Saúde , Técnicas de Reprodução Assistida , Brasil , Serviços de Planejamento Familiar/economia , Serviços de Planejamento Familiar/ética , Serviços de Planejamento Familiar/legislação & jurisprudência , Feminino , Preservação da Fertilidade/ética , Preservação da Fertilidade/legislação & jurisprudência , Acessibilidade aos Serviços de Saúde/ética , Acessibilidade aos Serviços de Saúde/legislação & jurisprudência , Disparidades em Assistência à Saúde/ética , Disparidades em Assistência à Saúde/legislação & jurisprudência , Humanos , Recém-Nascido , Infertilidade/economia , Infertilidade/epidemiologia , Infertilidade/terapia , Masculino , Gravidez , Direitos Sexuais e Reprodutivos/ética , Direitos Sexuais e Reprodutivos/legislação & jurisprudência , Técnicas de Reprodução Assistida/economia , Técnicas de Reprodução Assistida/ética , Técnicas de Reprodução Assistida/legislação & jurisprudênciaRESUMO
Studies on the cryopreservation of ovarian tissue usually compare slow freezing versus vitrification and aim to optimize protocols, evaluate combinations or concentrations of cryoprotectant agents (CPAs), exposure time, and the addition of synthetic polymers. This systematic review aimed to identify the different CPAs used for the vitrification of human or primate ovarian tissue and to compare their results in terms of follicular survival and functional preservation. We searched Pubmed and EMBASE for randomized clinical trials or cohort studies comparing CPAs for human and/or primate ovarian vitrification. The highest rate of morphologically normal follicles after cryopreservation was 98% and was obtained with a combination of 27% ethylene glycol (EG) plus 27% glycerol, in addition to non-permeable synthetic polymers. The use of dimethyl sulfoxide (DMSO) in relatively low concentrations combined with EG and other CPAs yielded more than 90% of intact follicles after vitrification. The methods and outcomes varied largely among studies, making it difficult to combine their results. While there is no definite answer to what is the best combination of CPAs for vitrification of human ovarian tissue, the data reviewed here suggest that current vitrification techniques are able to preserve the integrity of most follicles.
Assuntos
Criopreservação , Vitrificação , Animais , Criopreservação/métodos , Crioprotetores/farmacologia , Dimetil Sulfóxido , Etilenoglicol , FemininoRESUMO
The cryopreservation of human oocytes is an important strategy to spare fertility in women submitted to gonadotoxic therapy, ovarian surgery, or even to allow gestation by assisted reproduction technology after natural ovarian senescence. Methods to predict oocyte resistance to cryopreservation are still based on qualitative morphological assessment. In this study we evaluated whether morphometric characteristics of mature oocytes before vitrification and after warming are related to successful fertilization by intracytoplasmic sperm injection (ICSI). This was a prospective cohort study including 28 infertile women and 71 oocytes. Morphometric assessments included oocyte diameter, perivitelline space (PS), zona pellucida (ZP) and first polar body (PB). Out of 49 warmed oocytes, 27 (55%) survived cryopreservation and their pre-vitrification measures were similar to those of the 22 oocytes that perished. However, the oocytes that eventually failed to be fertilized had undergone more enlargement of the total diameter (pâ¯=â¯0.029) and shrinking of the PS (pâ¯=â¯0.033) after cryopreservation, compared to oocytes that were successfully fertilized. These findings suggest that the morphometric characteristics of fresh oocytes do not predict their survival to vitrification, while fertilization failure is associated with oocyte enlargement and PS shrinking after cryopreservation.
Assuntos
Criopreservação/métodos , Fertilização in vitro/métodos , Oócitos/citologia , Vitrificação , Adulto , Feminino , Humanos , Infertilidade Feminina , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas/métodos , Zona PelúcidaRESUMO
Fertility preservation in the cancer setting, known as oncofertility, is a field that requires cross-disciplinary interaction between physicians, basic scientists, clinical researchers, ethicists, lawyers, educators, and religious leaders. Funded by the National Institutes of Health, the Oncofertility Consortium (OC) was formed to be a scientifically grounded, transparent, and altruistic resource, both intellectual and monetary, for building this new field of practice capable of addressing the unique needs of young patients with cancer. The OC has expanded its attention to include other nonmalignant conditions that can threaten fertility, and the work of the OC now extends around the globe, involving partners who together have created a community of shared effort, resources, and practices. The OC creates materials that are translated, disseminated, and amended by all participants in the field, and local programs of excellence have developed worldwide to accelerate the pace and improve the quality of oncofertility research and practice. Here we review the global oncofertility programs and the capacity building activities that strengthen these research and clinical programs, ultimately improving patient care.
RESUMO
Purpose: In the accompanying article, "Survey of Fertility Preservation Options Available to Patients With Cancer Around the Globe," we showed that specific fertility preservation services may not be offered at various sites around the world because of cultural and legal barriers. We assessed global and regional experiences as well as the legal status of third-party reproduction and adoption to serve as a comprehensive international data set and resource for groups that wish to begin oncofertility interventions. Methods: We provide data on the legalities of third-party assisted reproductive technologies and other family-building options in the 28 oncofertility-practicing countries surveyed. Results: We found regional and country differences that will be important in the development of tailored resources for physicians and for patient brochures that are sensitive to these local restrictions and cultural norms. Conclusion: Because many patients first consult Web-based materials, the formal assessment of the availability of these options provides members of the global oncofertility community with data to which they might otherwise not have ready access to better serve their patients.
Assuntos
Preservação da Fertilidade , Neoplasias , Humanos , Poder Familiar , Encaminhamento e Consulta , Inquéritos e QuestionáriosRESUMO
Purpose: Oncofertility focuses on providing fertility and endocrine-sparing options to patients who undergo life-preserving but gonadotoxic cancer treatment. The resources needed to meet patient demand often are fragmented along disciplinary lines. We quantify assets and gaps in oncofertility care on a global scale. Methods: Survey-based questionnaires were provided to 191 members of the Oncofertility Consortium Global Partners Network, a National Institutes of Health-funded organization. Responses were analyzed to measure trends and regional subtleties about patient oncofertility experiences and to analyze barriers to care at sites that provide oncofertility services. Results: Sixty-three responses were received (response rate, 25%), and 40 were analyzed from oncofertility centers in 28 countries. Thirty of 40 survey results (75%) showed that formal referral processes and psychological care are provided to patients at the majority of sites. Fourteen of 23 respondents (61%) stated that some fertility preservation services are not offered because of cultural and legal barriers. The growth of oncofertility and its capacity to improve the lives of cancer survivors around the globe relies on concentrated efforts to increase awareness, promote collaboration, share best practices, and advocate for research funding. Conclusion: This survey reveals global and regional successes and challenges and provides insight into what is needed to advance the field and make the discussion of fertility preservation and endocrine health a standard component of the cancer treatment plan. As the field of oncofertility continues to develop around the globe, regular assessment of both international and regional barriers to quality care must continue to guide process improvements.
Assuntos
Sobreviventes de Câncer , Preservação da Fertilidade , Neoplasias , Fertilidade , Humanos , Neoplasias/terapia , Inquéritos e Questionários , Estados UnidosRESUMO
Fertility preservation in the cancer setting, known as oncofertility, is a field that requires cross-disciplinary interaction between physicians, basic scientists, clinical researchers, ethicists, lawyers, educators, and religious leaders. Funded by the National Institutes of Health, the Oncofertility Consortium (OC) was formed to be a scientifically grounded, transparent, and altruistic resource, both intellectual and monetary, for building this new field of practice capable of addressing the unique needs of young patients with cancer. The OC has expanded its attention to include other nonmalignant conditions that can threaten fertility, and the work of the OC now extends around the globe, involving partners who together have created a community of shared effort, resources, and practices. The OC creates materials that are translated, disseminated, and amended by all participants in the field, and local programs of excellence have developed worldwide to accelerate the pace and improve the quality of oncofertility research and practice. Here we review the global oncofertility programs and the capacity building activities that strengthen these research and clinical programs, ultimately improving patient care.
RESUMO
Malignant and cardiovascular diseases are the main causes of death in Brazil. Estimates for 2013 predict the occurrence of 189,150 new cases of cancer in Brazilian women. With advanced detection tools, patients are diagnosed and treated for cancer at a younger age and are more likely to survive. The cytotoxic action of chemotherapeutic agents and radiotherapy very frequently implies serious damage to the gonads, and consequences due to the hypoestrogenism, such as osteoporosis, infertility and premature ovarian failure, are expected. Oncofertility, then, appears as a new area of reproductive medicine, which is dedicated to the development of strategies for the reduction of therapeutic sequels in cancer survivals, ultimately aiming the maintenance of their quality of life and the possibility of biological maternity. This article aims to present an overview of possible options for female fertility preservation after cancer and future perspectives in oncofertility.