Ovarian cortex transplantation: 60 reported live births brings the success and worldwide expansion of the technique towards routine clinical practice

Angiopoietin-1 and -2 and vascular endothelial growth factor expression in ovarian grafts after cryopreservation using two methods

Objective

The favored method of preserving fertility in young female cancer survivors is cryopreservation and autotransplantation of ovarian tissue. Reducing hypoxia until angiogenesis takes place is essential for the survival of transplanted ovarian tissue. The aim of this study was to investigate the role of angiopoietin-1 (Angpt-1), angiopoietin-2 (Angpt-2), and vascular endothelial growth factor (VEGF) in ovarian tissue grafts that were cryopreserved using two methods.

Methods

Ovarian tissues harvested from ICR mice were divided into three groups: group I (control), no cryopreservation; group II, vitrification in EFS (ethylene-glycol, ficoll, and sucrose solution)-40; and group III, slow freezing in dimethyl sulfoxide. We extracted mRNA for VEGF, Angpt-1, and Angpt-2 from ovarian tissue 1 week following cryopreservation and again 2 weeks after autotransplantation. We used reverse transcriptase-polymerase chain reaction to quantify the levels of VEGF, Angpt-1, and Angpt-2 in the tissue.

Results

Angpt-1 and Angpt-2 expression decreased after cryopreservation in groups II and III. After autotransplantation, Angpt-1 and Angpt-2 expression in ovarian tissue showed different trends. Angpt-1 expression in groups II and III was lower than in group I, but Angpt-2 in groups II and III showed no significant difference from group I. The vitrified ovarian tissues had higher expression of VEGF and Angpt-2 than the slowfrozen ovarian tissues, but the difference was not statistically significant.

Conclusion

Our results indicate that Angpt-2 may play an important role in ovarian tissue transplantation after cryopreservation although further studies are needed to understand its exact function.

Sphingosine-1-phosphate reduces atresia of primordial follicles occurring during slow-freezing and thawing of human ovarian cortical strips

We aimed in this study to explore if sphingosine-1-phosphate (S1P) reduces apoptosis of primordial follicles during cryopreservation of human ovarian cortical samples. Ovarian cortical tissue fragments obtained from young patients who underwent laparoscopic excision of benign ovarian cysts were used for the experiments. The samples were slow-frozen and thawed with and without S1P at 200 and 400 μM, cultured for 1 day, and then were fixed and processed for both histomorphological assessment and detection of apoptosis with immunohistochemistry using apoptosis marker cleaved caspase-3. Follicle counts were expressed as the mean number of follicles per mm² . The mean number of primordial follicles and in vitro estradiol (E2) and anti-mullerian hormone (AMH) production of the slow-frozen and thawed samples were significantly reduced compared with fresh unfrozen samples. S1P treatment at 400 μM but not 200 μM concentration resulted in a significant increase in the number of surviving primordial follicles and in vitro E2 and AMH productions of the samples compared with their counterparts slow-frozen without S1P. We found that that there was a significant decrease in the number of primordial follicles with their oocytes stained positive for cleaved caspase-3 in the slow-frozen samples S1P 400 μM in comparison with the samples slow-frozen without S1P. These results suggest that S1P may ameliorate follicle atresia occurring in human ovarian cortical samples during cryopreservation.

Establishment of an improved vitrification protocol by combinations of vitrification medium for isolated mouse ovarian follicles

In vitro follicle growth (IVFG) is an emerging alternative option for fertility preservation in women instead of ovarian tissue cryopreservation and transplantation. To widen the application of this technique, follicle cryopreservation should be established prior to clinical use. In the present study, we tried to determine the optimal vitrification protocol of mouse ovarian follicle for in vitro culture and oocyte maturation by comparing four different compositions of cryoprotective agents (CPA). Secondary follicles were mechanically isolated from 2-week-old BDF-1 mice and randomly assigned to fresh control and four different groups by the composition of CPAs (ES, EDS, EFS and EPS groups; E: ethylene glycol, D: dimethyl sulfoxide, S: sucrose, F: ficoll, P: 1,2-propanediol (PROH)). After vitrification and warming procedures, the follicles were cultured in vitro for 10 days and then treated with human chorionic gonadotropin and epidermal growth factor to induce oocyte maturation. Fourteen to 16 h later, oocyte maturation and quality were assessed. Follicle viability was evaluated by Calcein-AM/ethidium homodimer-1 staining immediately after warming, and their survival and diameters were measured during follicle culture periods. Antral cavity formation was observed at the end of the culture period (on the 10th day of culture). Following oocyte maturation, its maturational ability and meiotic spindle formation were assessed to evaluate their competence. There was no significant difference in viability after warming among the vitrification groups. From the 8th day of culture, the survival rate of ES and EDS were significantly higher than those of other vitrification groups (EPS and EFS). The follicle diameter was largest in the fresh-control group from the 6th day, while smallest in the EFS with statistical significance. On the 10th day of culture, the antral-cavity formation rate of EDS was comparable to that of the fresh control group. However, the oocyte maturation was significantly decreased in all four vitrification groups when compared with control group; especially, the EFS showed a more marked reduction in the oocyte maturation. There were no significant differences in meiotic spindle formation among all of those groups. Our results suggest that EDS combination for mouse follicle vitrification are the most effective vitrification protocols for mouse follicle and evaluated by an in vitro culture and oocyte maturation after warming.

Retrievable hydrogels for ovarian follicle transplantation and oocyte collection

Cancer survivorship rates have drastically increased due to improved efficacy of oncologic treatments. Consequently, clinical concerns have shifted from solely focusing on survival to quality of life, with fertility preservation as an important consideration. Among fertility preservation strategies for female patients, ovarian tissue cryopreservation and subsequent reimplantation has been the only clinical option available to cancer survivors with cryopreserved tissue. However, follicle atresia after transplantation and risk of reintroducing malignant cells have prevented this procedure from becoming widely adopted in clinics. Herein, we investigated the encapsulation of ovarian follicles in alginate hydrogels that isolate the graft from the host, yet allows for maturation after transplantation at a heterotopic (i.e., subcutaneous) site, a process we termed in vivo follicle maturation. Survival of multiple follicle populations was confirmed via histology, with the notable development of the antral follicles. Collected oocytes (63%) exhibited polar body extrusion and were fertilized by intracytoplasmic sperm injection and standard in vitro fertilization procedures. Successfully fertilized oocytes developed to the pronucleus (14%), two-cell (36%), and four-cell (7%) stages. Furthermore, ovarian follicles cotransplanted with metastatic breast cancer cells within the hydrogels allowed for retrieval of the follicles, and no mice developed tumors after removal of the implant, confirming that the hydrogel prevented seeding of disease within the host. Collectively, these findings demonstrate a viable option for safe use of potentially cancer-laden ovarian donor tissue for in vivo follicle maturation within a retrievable hydrogel and subsequent oocyte collection. Ultimately, this technology may provide novel options to preserve fertility for young female patients with cancer.

Effect of sustained release of basic fibroblast growth factor using biodegradable gelatin hydrogels on frozen-thawed human ovarian tissue in a xenograft model

AIM

Ovarian tissue cryopreservation before cancer treatment is the only option to preserve fertility under some circumstances. However, tissue ischemia after transplantation while awaiting angiogenesis induces dysfunctional folliculogenesis and reduces ovarian reserve and is one of the disadvantages of frozen-thawed ovarian tissue transplantation. Basic fibroblast growth factor (bFGF) is a major regulator of angiogenesis. However, bFGF rapidly loses biological activity when its free form is injected in vivo. This study investigated whether administration of active bFGF helps establish a nurturing environment for follicular survival.

METHODS

A sheet form of a sustained release drug delivery system for bFGF was developed using biodegradable acidic gelatin hydrogel (bFGF sheet). The bFGF sheets or phosphate-buffered saline sheets, as a negative control, were transplanted with frozen-thawed human ovarian tissues subcutaneously into the backs of severe combined immunodeficient mice. Neovascularization, cell proliferation, fibrosis and follicular survival of ovarian grafts were analyzed at 6 weeks after xenografting.

RESULTS

The bFGF sheets were optimized to release bFGF for at least 10 days. The transplantation of bFGF sheets with frozen-thawed ovarian tissues significantly increased human and mouse CD31-positive areas and stromal and endothelial cell proliferations. The administration of bFGF also significantly decreased the percentage of the fibrotic area in the graft, resulting in a significant increase in primordial and primary follicular density.

CONCLUSION

Local administration of a sustained release of biologically active bFGF induced neovascularization in frozen-thawed ovarian tissue grafts, which could establish the nurturing environment required for follicular survival in heterotopic xenografts.

Update on fertility preservation from the Barcelona International Society for Fertility Preservation-ESHRE-ASRM 2015 expert meeting: indications, results and future perspectives

STUDY QUESTION

What progress has been made in fertility preservation (FP) over the last decade?

SUMMARY ANSWER

FP techniques have been widely adopted over the last decade and therefore the establishment of international registries on their short- and long-term outcomes is strongly recommended.

WHAT IS KNOWN ALREADY

FP is a fundamental issue for both males and females whose future fertility may be compromised. Reproductive capacity may be seriously affected by age, different medical conditions and also by treatments, especially those with gonadal toxicity. There is general consensus on the need to provide counselling about currently available FP options to all individuals wishing to preserve their fertility.

STUDY DESIGN, SIZE, DURATION

An international meeting with representatives from expert scientific societies involved in FP was held in Barcelona, Spain, in June 2015.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Twenty international FP experts belonging to the American Society of Reproductive Medicine, ESHRE and the International Society of Fertility Preservation reviewed the literature up to June 2015 to be discussed at the meeting, and approved the final manuscript. At the time this manuscript was being written, new evidence considered relevant for the debated topics was published, and was consequently included.

MAIN RESULTS AND THE ROLE OF CHANCE

Several oncological and non-oncological diseases may affect current or future fertility, either caused by the disease itself or the gonadotoxic treatment, and need an adequate FP approach. Women wishing to postpone maternity and transgender individuals before starting hormone therapy or undergoing surgery to remove/alter their reproductive organs should also be counselled accordingly. Embryo and oocyte cryopreservation are first-line FP methods in post-pubertal women. Metaphase II oocyte cryopreservation (vitrification) is the preferred option. Cumulative evidence of restoration of ovarian function and spontaneous pregnancies after ART following orthotopic transplantation of cryopreserved ovarian tissue supports its future consideration as an open clinical application. Semen cryopreservation is the only established method for FP in men. Testicular tissue cryopreservation should be recommended in pre-pubertal boys even though fertility restoration strategies by autotransplantation of cryopreserved testicular tissue have not yet been tested for safe clinical use in humans. The establishment of international registries on the short- and long-term outcomes of FP techniques is strongly recommended.

LIMITATIONS, REASONS FOR CAUTION

Given the lack of studies in large cohorts or with a randomized design, the level of evidence for most of the evidence reviewed was three or below.

WIDER IMPLICATIONS OF THE FINDINGS

Further high quality studies are needed to study the long-term outcomes of FP techniques.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

N/A.

Fertility preservation in children and adolescents: current options and considerations

PURPOSE OF REVIEW

The purpose of this review is to outline current pediatric fertility preservation options, and discuss ethical and financial considerations impacting this rapidly expanding field.

RECENT FINDINGS

With the improvement in treatment of pediatric malignancies and medical conditions that threaten fertility, survival rates are increasing. Therefore, minimizing long-term morbidities such as gonadal damage and infertility is of utmost importance. Impaired fertility not only has a significant negative impact on patient's quality of life; in women, gonadal damage puts patients at risk for premature menopause, and increased risk of cardiac, skeletal, and cognitive issues. Fortunately, fertility preservation options exist for both female and male prepubertal and pubertal patients, and discussion of such options with patients and their families prior to the initiation of therapy and/or before further deterioration of gonadal function is crucial. A multidisciplinary approach to fertility counseling, with attention to the patient's goals and cultural beliefs, is ideal.

SUMMARY

Although several national organizations support integrating a fertility consultation into routine care, fertility preservation is still underutilized. Continued research is needed to understand barriers for patients/families and reduce the number of missed opportunities for fertility preservation.

Co-transplantation of Human Ovarian Tissue with Engineered Endothelial Cells: A Cell-based Strategy Combining Accelerated Perfusion with Direct Paracrine Delivery

Infertility is a frequent side effect of chemotherapy and/or radiotherapy and for some patients, cryopreservation of oocytes or embryos is not an option. As an alternative, an increasing number of these patients are choosing to cryopreserve ovarian tissue for autograft following recovery and remission. Despite improvements in outcomes among patients undergoing auto-transplantation of cryopreserved ovarian tissue, efficient revascularization of grafted tissue remains a major obstacle. To mitigate ischemia and thus improve outcomes in patients undergoing auto-transplantation, we developed a vascular cell-based strategy for accelerating perfusion of ovarian tissue. We describe a method for co-transplantation of exogenous endothelial cells (ExECs) with cryopreserved ovarian tissue in a mouse xenograft model. We extend this approach to employ ExECs that have been engineered to constitutively express Anti-Mullerian hormone (AMH), thus enabling sustained paracrine signaling input to ovarian grafts. Co-transplantation with ExECs increased follicular volume and improved antral follicle development, and AMH-expressing ExECs promoted retention of quiescent primordial follicles. This combined strategy may be a useful tool for mitigating ischemia and modulating follicular activation in the context of fertility preservation and/or infertility at large.

Successful fertility following optimized perfusion and cryopreservation of whole ovary and allotransplantation in a premature ovarian insufficiency rat model

Background

Fertility preservation by whole ovary cryopreservation and transplantation (WOCP&TP) with vascular anastomosis requires successful cryopreservation. In this study, we investigated the possibility of restoring ovarian function and natural fertility after WOCP&TP in a premature ovarian insufficiency (POI) rat model. The influence of cryopreservation on the offspring of rats following WOCP&TP was also explored.

Method

Rats aged 8-10 weeks were used as donors and recipients for allotransplantation. Fifteen rat whole ovaries were divided into three groups: the optimized group, the conventional group, and the fresh group. Different perfusion modes were used before cryopreservation and after thawing. Whole ovaries were observed by morphologic analysis, immunohistochemical staining, and transferase-mediated deoxyuridine triphosphate nick end-labeling assay. Ovarian function and fertility after WOCP&TP were then observed in 25 cyclophosphamide-induced POI rats for 8 months. Ovarian function was assessed by vaginal smears and blood hormone levels. Fertility restoration was quantified as the live birth rate after mating. The filial generation of rats was mated at 8-10 weeks of age. Offspring were observed for birth defect.

Results

Histological evaluation demonstrated intact morphology of follicles in all groups, with 77.6% of the total number of follicles identified as intact in the optimized group. The apoptotic rates of ovarian cells in the optimized group were significantly lower than that in the conventional group. Of the 20 live POI rats, 14 (70%) began to recover ovarian function after 2 weeks of transplantation, with normal hormone levels achieved 4 weeks after transplantation. Four of 14 rats were pregnant and delivered live offspring. One rat had a second pregnancy and delivered a second litter of live offspring. When the offspring matured, they were mated, and second and third generations of rats were born. All offspring had no abnormalities in appearance.

Conclusions

High rates of restoration of ovarian function and natural fertility with multiple generations of offspring were obtained following WOCP&TP in a cyclophosphamide-induced POI rat model by utilizing optimized perfusion. Cryopreservation did not affect the viability of successive generations.

In vitro maturation of oocytes from excised ovarian tissue in a patient with autoimmune ovarian insufficiency possibly associated with Epstein-Barr virus infection

BACKGROUND

Some reports show that it is possible to isolate immature oocytes from human ovarian tissue retrieved by a cortex biopsy or ovariectomy of non-stimulated ovaries and mature them in vitro. The mature oocytes can be vitrified and stored for in vitro fertilization, which, along with ovarian tissue cryopreservation, is mostly practiced in young cancer patients to preserve their fertility. There is much less data on this new approach in women with a natural ovarian insufficiency, which can be caused by different factors, including viral infection. In this case report this advanced methodology was used in a young patient suffering from ovarian insufficiency which was possibly associated with Epstein-Barr virus and infectious mononucleosis (glandular fever).

METHODS

This case report included a 27-year-old patient who attended our infertility clinic because of ovarian failure as a part of autoimmune polyendocrinopathy that occurred after Epstein-Barr virus infection, which has rarely been reported until now. Although antral follicles were observed in her ovaries by ultrasound monitoring, she was amenorrhoeic with menopausal concentrations of follicle-stimulating hormone (FSH) and without mature follicles. Therefore, a small biopsy of ovarian cortex tissue was performed using laparoscopy to retrieve immature oocytes. The retrieved oocytes were matured in vitro, cryopreserved, and stored for in vitro fertilization and potential pregnancy.

RESULTS

Four immature, germinal vesicle (GV) oocytes were found and removed from tissue, denuded mechanically by a pipette, and matured in vitro in a maturation medium with added FSH and hCG as well as in co-culture with cumulus cells, which were retrieved by their denudation. Three oocytes matured in vitro to the metaphase II (MII) stage and were vitrified for in vitro fertilization along with ovarian tissue cryopreservation.

CONCLUSION

Our results show that Epstein-Barr infection is possibly associated with autoimmune ovarian failure. The devastating impact on fertility in such disorder can be successfully avoided by in vitro maturation of oocytes from excised ovarian tissue.

Comparison of the Oocyte Quality Derived from Two-Dimensional Follicle Culture Methods and Developmental Competence of In Vitro Grown and Matured Oocytes

In vitro follicle growth (IVFG) is an emerging fertility preservation technique, which can obtain fertilizable oocytes from an in vitro culture system in female. This study aimed to compare efficiency of the most widely used two-dimensional follicle culture methods [with or without oil layer (O+ or O- group)]. Preantral follicles were isolated from mice and randomly assigned. Follicles were cultured for 10 days and cumulus-oocyte complexes harvested 16-18 hours after hCG treatment. Follicle and oocyte growth, hormones in spent medium, meiotic spindle localization, expression of reactive oxygen species (ROS), mitochondrial activity, and gene expression were evaluated. In follicle growth, survival, pseudoantral cavity formation, ovulation, and oocyte maturation were also significantly higher in O+ group than O- group. Hormone production was significantly higher in follicles cultured in O+ than O-. There were no significant differences in mRNA expression related to development. On the other hand, the level of ROS was increased while the mitochondrial activity of in vitro grown matured oocyte was less than in vivo matured oocytes. In conclusion, follicle culture with O+ group appears to be superior to the culture in O- group in terms of follicle growth, development, oocyte growth, maturation, and microorganelles in oocyte.

Preliminary human application of optical coherence tomography for quantification and localization of primordial follicles aimed at effective ovarian tissue transplantation

Purpose

The purpose of this study was to evaluate the possible clinical application of optical coherence tomography for assessing ovarian reserve in individual specimens of human ovarian tissue for fertility preservation.

Methods

Ovarian tissue examination by optical coherence tomography was performed before ovarian tissue cryopreservation. Three of the four subjects had hematological disease or cancer, and they faced a threat to their fertility due to impending chemotherapy. One patient underwent ovarian tissue extraction for in vitro activation of dormant follicles as fertility treatment.

Results

The current full-field optical coherence tomography technique can detect primordial follicles in non-fixed and non-embedded human ovarian tissue. These images are well correlated with histological evaluation and the ovarian reserve test, including follicle counts.

Conclusion

It was demonstrated that optical coherence tomography could assess localization of primordial follicles and ovarian reserve in specimens of non-fixed human ovarian cortex, although optimization for examination of human ovarian tissue is needed for clinical application. Additionally, this technique holds the possibility of assessing the ovarian reserve of patients with unevaluable ovarian reserve.

Trial registration number

UMIN000023141

Clinical application of serum anti-Müllerian hormone as an ovarian reserve marker: A review of recent studies

It has been more than 15 years since the measurement of serum anti-Müllerian hormone (AMH) first allowed the quantitative assessment of ovarian reserve. Meanwhile, the clinical implication of serum AMH has been expanding. The measurement of serum AMH has been applied in various clinical fields, including assisted reproduction, menopause, reproductive disorders and assessment of ovarian damage/toxicity. Well-known findings about the usefulness of serum AMH revealed by numerous studies executed in the early era include decline with aging, a good correlation with oocyte yield in assisted reproduction, upregulation in polycystic ovarian syndrome and a decrease on ovarian surgery and toxic treatment. More intensive research, including a meta-analysis, cutting-edge clinical trial and advances in AMH assays, has yielded newer findings and firmer clinical interpretations in serum AMH in the past few years. Variations in the AMH decline trajectory in the general population do not support the accurate prediction of menopause. The ability to predict pregnancy in infertility treatment and natural conception is poor, while a nomogram integrating serum AMH as a stimulation protocol is useful for avoiding poor and/or hyper-responses. On the other hand, improvements in measuring very low concentrations of serum AMH may be capable of distinguishing women with poor ovarian function. Age-independent standardization of AMH values may be helpful for comparing ovarian reserves among women at different ages.

Expression of inhibitor proteins that control primordial follicle reserve decreases in cryopreserved ovaries after autotransplantation

PURPOSE

Even with 86 live births reported globally so far, the mechanism of primordial follicle loss following autotransplantation of the frozen-thawed ovarian tissue needs further evaluation. Pten, Tsc1, p27, and Amh are the inhibitor proteins that play crucial roles in suppressing the transition from the primordial follicle to primary state, maintaining the primordial follicle reserve. In this study, we aimed to evaluate whether the expression patterns of these proteins change and it may be related to the global primordial follicle loss after autotransplantation of the frozen-thawed ovarian tissue.

METHODS

Four groups were established in rats: fresh-control, frozen/thawed, fresh-transplanted, and frozen/thawed and transplanted. After slow freezing and thawing process, two ovarian pieces were transplanted into the back muscle of the same rat. After 2 weeks, grafts were harvested, fixed, and embedded into the paraffin block. Normal and atretic primordial/growing follicle count was performed in all groups. Ovarian tissues were evaluated for the dynamic expressions of the Pten, Tsc1, p27, and Amh proteins using immunohistochemistry, and H-score analyses were done.

RESULTS

Ovarian tissue cryopreservation does not change the expression patterns of inhibitory proteins that control ovarian reserve. Both in fresh and frozen/thawed autotransplanted groups, the expression of inhibitory proteins and Amh decreased significantly in primordial follicles and in growing follicles, respectively. In control group and in frozen/thawed group, primordial follicle counts were similar but decreased by almost half in both fresh-transplanted and frozen/thawed and transplanted groups.

CONCLUSIONS

One of the causes of primordial follicle loss after transplantation of ovarian graft may be decreased expression of the inhibitory proteins that guard the ovarian reserve and transplantation itself seems to be the major cause for disruption of inhibitory molecular signaling. Our findings highlight important molecular aspects for future clinical applications for fertility preservation in humans.

Criopreserved ovarian tissue transplantation and bone restoration metabolism in castrated rats

OBJECTIVES

to evaluate estradiol levels and autotransplantation heated ovarian tissue effects, after vitrification, on rats bone metabolism previously oophorectomized bilaterally.

METHODS

experimental study with 27 rats aged 11 to 12 weeks and weighing 200g to 300g, submitted to bilateral oophorectomy and ovarian tissue cryopreservation for subsequent reimplantation. Animals were divided into two groups, A and B, with 8 and 19 rats, respectively. Autotransplantation occurred in two periods according to castration time: after one week, in group A, and after one month in group B. Serum estradiol measurements and ovary and tibia histological analysis were performed before and after oophorectomy period (early or late) and one month after reimplantation.

RESULTS

in groups A and B, tibia median cortical thickness was 0.463±0.14mm (mean±SD) at the baseline, 0.360±0.14mm after oophorectomy and 0.445±0.17mm one month after reimplantation p<0.005). Trabecular means were 0.050±0.08mm (mean±SD) at baseline, 0.022±0.08mm after oophorectomy and 0.049±0.032mm one month after replantation (p<0.005). There was no statistical difference in estradiol variation between the two study groups (p=0.819).

CONCLUSION

cryopreserved ovarian tissue transplantation restored bone parameters, and these results suggest that ovarian reimplantation in women may have the same beneficial effects on bone metabolism.

Effect of mouse ovarian tissue cryopreservation by vitrification with Rapid-i closed system

PURPOSE

Currently, open systems are mainly used for cryopreservation of ovarian tissue, oocytes, and embryos, but there is a potential risk of contamination. This study was performed to assess ovarian tissue cryopreservation by a closed vitrification system (Rapid-i vitrification system™), which is already used clinically for oocyte/embryo cryopreservation.

METHODS

Ovaries of C57BL/6J mice were frozen and thawed by using the Rapid-i vitrification system™ (Rapid-i) followed by implantation into recipient mice. Hematoxylin-eosin staining was performed for histological examination of the frozen-thawed ovaries to assess follicle grade. Fertility after implantation of the ovaries was assessed from the live birth rate and the number of live pups.

RESULTS

There was no significant difference in grade 1 primary follicles between fresh ovaries (control group, 94.2 ± 2.9%) and frozen-thawed ovaries (Rapid-i group, 87.1 ± 1.8%). However, there was a significant decrease in grade 1 early and late secondary follicles in the Rapid-i group compared with the control group. The live-birth rate was significantly lower in the Rapid-i group compared with the control group (29.2 vs. 83.3%, p < 0.05). On the other hand, there was no significant difference in the average number of live pups between the control group and the Rapid-i group (3 ± 0.4 vs. 2.7 ± 0.3).

CONCLUSIONS

The Rapid-i seems to be effective for cryopreservation of mouse ovarian tissue. Under appropriate conditions, the Rapid-i could be employed for ovarian tissue cryopreservation and preservation of fertility in humans.

A novel fibrin-based artificial ovary prototype resembling human ovarian tissue in terms of architecture and rigidity

PURPOSE

The aim of this study is to optimize fibrin matrix composition in order to mimic human ovarian tissue architecture for human ovarian follicle encapsulation and grafting.

METHODS

Ultrastructure of fresh human ovarian cortex in age-related women (n = 3) and different fibrin formulations (F12.5/T1, F30/T50, F50/T50, F75/T75), rheology of fibrin matrices and histology of isolated and encapsulated human ovarian follicles in these matrices.

RESULTS

Fresh human ovarian cortex showed a highly fibrous and structurally inhomogeneous architecture in three age-related patients, but the mean ± SD of fiber thickness (61.3 to 72.4 nm) was comparable between patients. When the fiber thickness of four different fibrin formulations was compared with human ovarian cortex, F50/T50 and F75/T75 showed similar fiber diameters to native tissue, while F12.5/T1 was significantly different (p value < 0.01). In addition, increased concentrations of fibrin exhibited enhanced storage modulus with F50/T50, resembling physiological ovarian rigidity. Excluding F12.5/T1 from further analysis, only three remaining fibrin matrices (F30/T50, F50/T50, F75/T75) were histologically investigated. For this, frozen-thawed fragments of human ovarian tissue collected from 22 patients were used to isolate ovarian follicles and encapsulate them in the three fibrin formulations. All three yielded similar follicle recovery and loss rates soon after encapsulation. Therefore, based on fiber thickness, porosity, and rigidity, we selected F50/T50 as the fibrin formulation that best mimics native tissue.

CONCLUSIONS

Of all the different fibrin matrix concentrations tested, F50/T50 emerged as the combination of choice in terms of ultrastructure and rigidity, most closely resembling human ovarian cortex.

Allogeneic ovarian transplantation using immunomodulator preimplantation factor (PIF) as monotherapy restored ovarian function in olive baboon

PURPOSE

Allogeneic ovarian transplantation may be an alternative in the future to oocyte donation in women with premature ovarian failure. The objectives of this study were to (a) evaluate allotransplantation feasibility for restoration of ovarian function and (b) assess efficacy of synthetic preimplantation factor (PIF) monotherapy as sole immune-acceptance regimen.

METHODS

This is an experimental animal study using non-human primates (Papio anubis). Allogeneic orthotopic ovarian tissue transplantation was performed in two female olive baboons. PIF was administered as a monotherapy to prevent immune rejection and achieve transplant maintenance and function. Subjects underwent bilateral oophorectomy followed by cross-transplantation of prepared ovarian cortex. Postoperatively, subjects were monitored for clinical and biochemical signs of graft rejection and return of function. Weekly blood samples were obtained to monitor graft acceptance and endocrine function restoration.

RESULTS

Postoperatively, there were no clinical signs of rejection. Laboratory parameters (alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatinine) did not indicate organ rejection at any stage of the experiment. Initially, significant loss of follicles was noticed after grafting and serum follicle-stimulating hormone (FSH) and E2 levels were consistent with ovarian failure. Seven months after transplantation, one animal exhibited recurrence of ovarian endocrine function (perineal swelling, E2 rise, FSH decrease, and return of menstruation).

CONCLUSIONS

Organ rejection after allogeneic ovarian transplantation was prevented using PIF as monotherapy for the first time and no side effects were recorded. The study suggests the clinical feasibility of ovarian allotransplantation to obtain ovarian function.

Ethics of fertility preservation for prepubertal children: should clinicians offer procedures where efficacy is largely unproven?

Young children with cancer are treated with interventions that can have a high risk of compromising their reproductive potential. 'Fertility preservation' for children who have not yet reached puberty involves surgically removing and cryopreserving reproductive tissue prior to treatment in the expectation that strategies for the use of this tissue will be developed in the future. Fertility preservation for prepubertal children is ethically complex because the techniques largely lack proven efficacy for this age group. There is professional difference of opinion about whether it is ethical to offer such 'experimental' procedures. The question addressed in this paper is: when, if ever, is it ethically justifiable to offer fertility preservation surgery to prepubertal children? We present the ethical concerns about prepubertal fertility preservation, drawing both on existing literature and our experience discussing this issue with clinicians in clinical ethics case consultations. We argue that offering the procedure is ethically justifiable in certain circumstances. For many children, the balance of benefits and burdens is such that the procedure is ethically permissible but not ethically required; when the procedure is medically safe, it is the parents' decision to make, with appropriate information and guidance from the treating clinicians. We suggest that clinical ethics support processes are necessary to assist clinicians to engage with the ethical complexity of prepubertal fertility preservation and describe the framework that has been integrated into the pathway of care for patients and families attending the Royal Children's Hospital in Melbourne, Australia.

Fertility preservation for patients with breast cancer: The Korean Society for Fertility Preservation clinical guidelines

With advances in the methods of cancer treatment used in modern medicine, the number of breast cancer survivors has been consistently rising. As the number of women who wish to become pregnant after being diagnosed with breast cancer increases, it is necessary to consider fertility preservation in these patients. However, medical doctors may be unaware of the importance of fertility preservation among cancer patients because most patients do not share their concerns about fertility with their doctors. Considering the time spent choosing and undergoing treatment, an early referral to a reproductive specialist is the best way to prevent a delay in cancer treatment. Since it is not easy to make decisions on matters related to cancer diagnosis and fertility, patients should be provided with enough time for decision-making, and to allow for this, an early referral will provide patients with sufficient time to choose an appropriate method of fertility preservation. The currently available options of fertility preservation for patients with breast cancer include cryopreservation of embryos, oocytes, and ovarian tissue and gonadotropin-releasing hormone agonist treatment before and during chemotherapy. An appropriate method of fertility preservation must be selected through consultations between individual patients and health professionals and analyses of the pros and cons of different options.

In vivo transplantation of 3D encapsulated ovarian constructs in rats corrects abnormalities of ovarian failure

Safe clinical hormone replacement (HR) will likely become increasingly important in the growing populations of aged women and cancer patients undergoing treatments that ablate the ovaries. Cell-based HRT (cHRT) is an alternative approach that may allow certain physiological outcomes to be achieved with lower circulating hormone levels than pharmacological means due to participation of cells in the hypothalamus-pituitary-ovary feedback control loop. Here we describe the in vivo performance of 3D bioengineered ovarian constructs that recapitulate native cell-cell interactions between ovarian granulosa and theca cells as an approach to cHRT. The constructs are fabricated using either Ca++ or Sr++ to crosslink alginate. Following implantation in ovariectomized (ovx) rats, the Sr++-cross-linked constructs achieve stable secretion of hormones during 90 days of study. Further, we show these constructs with isogeneic cells to be effective in ameliorating adverse effects of hormone deficiency, including bone health, uterine health, and body composition in this rat model.

Ovarian and Uterine Functions in Female Survivors of Childhood Cancers

Adult survivors of childhood cancers are more prone to developing poor reproductive and obstetrical outcomes than their siblings and the general population as a result of previous exposure to chemotherapy and radiation during childhood. Chemotherapy drugs exert cytotoxic effects systemically and therefore can damage the ovaries, leading to infertility, premature ovarian failure, and, to a lesser extent, spontaneous abortions. They have very limited or no deleterious effects on the uterus that can be recognized clinically. By contrast, radiation is detrimental to both the ovaries and the uterus, thereby causing a greater magnitude of adverse effects on the female reproductive function. These include infertility, premature ovarian failure, miscarriage, fetal growth restrictions, perinatal deaths, preterm births, delivery of small-for-gestational-age infants, preeclampsia, and abnormal placentation. Regrettably, the majority of these adverse outcomes arise from radiation-induced uterine injury and are reported at higher incidence in the adult survivors of childhood cancers who were exposed to uterine radiation during childhood in the form of pelvic, spinal, or total-body irradiation. Recent findings of long-term follow-up studies evaluating reproductive performance of female survivors provided some reassurance to female cancer survivors by documenting that pregnancy and live birth rates were not significantly compromised in survivors, including those who had been treated with alkylating agents and had not received pelvic, cranial, and total-body irradiation. We aimed in this narrative review article to provide an update on the impact of chemotherapy and radiation on the ovarian and uterine function in female survivors of childhood cancer.

IMPLICATIONS FOR PRACTICE

Adult survivors of childhood cancers are more prone to developing a number of poor reproductive and obstetrical outcomes than their siblings and the general population as a result of previous exposure to chemotherapy and radiation during childhood. The impact of radiation therapy on the female genital system is greater than chemotherapy regimens because radiation is detrimental to both the uterus and the ovaries, whereas toxic effects of chemotherapy drugs are confined to the ovaries. Therefore, radiation-induced uterine damage accounts for most poor obstetrical outcomes in the survivors. These include infertility, miscarriages, stillbirths, fetal growth restrictions, preeclampsia, and preterm deliveries.

Female fertility preservation in the pediatric and adolescent cancer patient population

The 5-year survival rate for childhood cancer is over 80%, thereby increasing the number of young women facing infertility in the future because of the gonadotoxic effects of chemotherapy and radiation. The gonadotoxic effects of childhood cancer treatment vary by the radiation regimen and the chemotherapeutic drugs utilized. Although the American Society of Clinical Oncology guidelines recommend fertility preservation for all patients, there are several barriers and ethical considerations to fertility preservation in the pediatric and adolescent female population. Additionally, the fertility preservation methods for pre- and postpubertal females differ, with only experimental methods available for prepubertal females. We will review the risk of chemotherapy and radiation on female fertility, the approach to fertility preservation in the pediatric and adolescent female population, methods of fertility preservation for both pre- and postpubertal females, barriers to fertility preservation, cost, and psychological and ethical considerations.

A modified and tailored human follicle isolation procedure improves follicle recovery and survival

Background

Ovarian tissue cryopreservation followed by transplantation after cancer remission is the most commonly applied fertility restoration approach in very young girls and women who require immediate cancer therapy. However, clinicians strongly advise against reimplantation of one’s own ovarian tissue when there is a high risk of recurrence after grafting. For these patients, development of an alternative strategy, namely a transplantable artificial ovary, offers future hope of conceiving. The first essential requirement for an artificial ovary is the set-up of a safe and effective follicle isolation procedure. Despite encouraging results with different variants of this technique, none of them take into the account the physiology and great variability in follicular density inside individual tissue fragments and between different patients. The goal of this study was to improve our previously applied follicle isolation procedure in order to develop a tailored isolation procedure for human follicles according to individual tissue properties. To this end, enzymatic digestion was divided into three time intervals in order to initially recover the first follicles to be isolated, and then further dissociate undigested fragments of tissue containing entrapped follicles.

Results

After thawing frozen human ovarian tissue using a modified and tailored follicle isolation method, already 35% of follicles were fully isolated and recovered after 30 min of enzymatic digestion. Indeed, this protocol resulted in a higher follicle yield (p < 0.01) and greater numbers of primordial and primary follicles (p < 0.05) than the previous approach. However, no significant difference was found in caspase-3-positive and Ki67-positive staining between the two isolation protocols. In addition, greater follicle quality was demonstrated. When human follicles isolated using the modified protocol were encapsulated in a fibrin matrix with high concentrations of fibrinogen and thrombin and xenografted to a SCID mouse, more follicles were found to be healthy after one week of transplantation than in a previous our study.

Conclusions

With the modified follicle isolation method, we were able to maximize the number and quality of isolated primordial and primary follicles, and develop a tailored follicle isolation procedure according to individual tissue properties. Moreover, improved follicle survival inside an artificial ovary prototype was detected after one week of xenografting.

Electronic supplementary material

The online version of this article (10.1186/s13048-017-0366-8) contains supplementary material, which is available to authorized users.

Subcutaneous ovarian tissue transplantation in nonhuman primates: duration of endocrine function and normalcy of subsequent offspring as demonstrated by reproductive competence, oocyte production, and telomere length

PURPOSE

The main purposes of the study were to investigate the endocrine function of ovarian tissue transplanted to heterotopic subcutaneous sites and the reproductive competence and telomere length of a nonhuman primate originating from transplanted tissue.

METHODS

Ovarian cortex pieces were transplanted into the original rhesus macaques in the arm subcutaneously, in the abdomen next to muscles, or in the kidney. Serum estradiol (E2) and progesterone (P4) concentrations were measured weekly for up to 8 years following tissue transplantation. A monkey derived from an oocyte in transplanted ovarian tissue entered time-mated breeding and underwent controlled ovarian stimulation. Pregnancy and offspring were evaluated. Telomere lengths and oocytes obtained following controlled ovarian stimulation were assessed.

RESULTS

Monkeys with transplants in the arm and abdomen had cyclic E2 of 100 pg/ml, while an animal with arm transplants had E2 of 50 pg/ml. One monkey with transplants in the abdomen and kidney had ovulatory cycles for 3 years. A monkey derived from an oocyte in transplanted tissue conceived and had a normal gestation until intrapartum fetal demise. She conceived again and delivered a healthy offspring at term. Controlled ovarian stimulations of this monkey yielded mature oocytes comparable to controls. Her telomere length was long relative to controls.

CONCLUSIONS

Heterotopic ovarian tissue transplants yielded long-term endocrine function in macaques. A monkey derived from an oocyte in transplanted tissue was reproductively competent. Her telomere length did not show epigenetically induced premature cellular aging. Ovarian tissue transplantation to heterotopic sites for fertility preservation should move forward cautiously, yet optimistically.

"Tissue Papers" from Organ-Specific Decellularized Extracellular Matrices

Using an innovative, tissue-independent approach to decellularized tissue processing and biomaterial fabrication, the development of a series of "tissue papers" derived from native porcine tissues/organs (heart, kidney, liver, muscle), native bovine tissue/organ (ovary and uterus), and purified bovine Achilles tendon collagen as a control from decellularized extracellular matrix particle ink suspensions cast into molds is described. Each tissue paper type has distinct microstructural characteristics as well as physical and mechanical properties, is capable of absorbing up to 300% of its own weight in liquid, and remains mechanically robust (E = 1-18 MPa) when hydrated; permitting it to be cut, rolled, folded, and sutured, as needed. In vitro characterization with human mesenchymal stem cells reveals that all tissue paper types support cell adhesion, viability, and proliferation over four weeks. Ovarian tissue papers support mouse ovarian follicle adhesion, viability, and health in vitro, as well as support, and maintain the viability and hormonal function of nonhuman primate and human follicle-containing, live ovarian cortical tissues ex vivo for eight weeks postmortem. "Tissue papers" can be further augmented with additional synthetic and natural biomaterials, as well as integrated with recently developed, advanced 3D-printable biomaterials, providing a versatile platform for future multi-biomaterial construct manufacturing.

Engineered endothelium provides angiogenic and paracrine stimulus to grafted human ovarian tissue

Despite major advances in tissue cryopreservation and auto-transplantation, reperfusion ischemia and hypoxia have been reported as major obstacles to successful recovery of the follicular pool within grafted ovarian tissue. We demonstrate a benefit to follicular survival and function in human ovarian tissue that is co-transplanted with exogenous endothelial cells (ExEC). ExECs were capable of forming functionally perfused vessels at the host/graft interface and increased both viability and follicular volume in ExEC-assisted grafts with resumption of antral follicle development in long-term grafts. ExECs that were engineered to constitutively express anti-mullerian hormone (AMH) induced a greater proportion of quiescent primordial follicles than control ExECs, indicating suppression of premature mobilization that has been noted in the context of ovarian tissue transplantation. These findings present a cell-based strategy that combines accelerated perfusion with direct paracrine delivery of a bioactive payload to transplanted ovarian tissue.

Expectations and limitations of ovarian tissue transplantation

Constant progress in the diagnosis and treatment of cancer disease has increased the number and prognosis of cancer survivors. However, the toxic effects of chemotherapy and radiotherapy on ovarian function have resulted in premature ovarian failure. Patients are, therefore, still expecting methods to be developed to preserve their fertility successfully. Several potential options are available to preserve fertility in patients who face premature ovarian failure, including immature or mature oocyte and embryo cryopreservation. However, for children or prepubertal women needing immediate chemotherapy, cryopreservation of ovarian tissue is the only alternative. The ultimate aim of this strategy is to implant ovarian tissue into the pelvic cavity (orthotopic site) or in a heterotopic site once oncological treatment is completed and the patient is disease free. Transplantation of ovarian tissue with sufficiently large numbers of follicles could potentially restore endocrine function and allow multiple cycles for conception. However, the success of ovarian tissue transplantation still has multiple challenges, such as the low number of follicles in the graft that may affect their longevity as well as the survival of the tissue during ex vivo processing and subsequent transplantation. Therefore, this review aims to summarize the achievements of ovary grafting and the potential techniques that have been developed to improve ovarian graft survival.

Fertility Preservation in Endometriosis Patients: Anti-Müllerian Hormone Is a Reliable Marker of the Ovarian Follicle Density

OBJECTIVE

To analyze the ovarian reserve via measurement of follicular density and anti-Müllerian hormone (AMH) in endometriosis patients participating to a clinical program of cortical ovarian cryopreservation.

DESIGN

Retrospective analysis of serum AMH levels and prospective investigation of ovarian follicle number.

SETTING

University Hospital.

PATIENTS

Two hundred and two women with endometriosis and 400 controls.

INTERVENTIONS

Blood samples and ovarian biopsies.

MAIN OUTCOME MEASURES

Correlation of serum AMH levels and the number of non-growing follicles in the biopsied cortical tissues in endometriosis and control subjects, including age, type of AMH kit, and the laboratory performing the analysis as covariates.

RESULTS

AMH levels were shown to decrease with age in untreated endometriosis patients (P < 1.0 × 10^-5) but they were significantly lower in endometriosis compared to controls only in patients over 36 years old (P = 2.7 × 10^-4). The AMH decrease was faster in endometriosis compared to controls (beta = 0.27, P = 4.0 × 10^-4). Primordial follicle number decreased with the reduction of AMH levels in both cases and controls (beta = 0.3; P = 0.04).

CONCLUSION

AMH is a reliable marker of ovarian reserve in endometriosis patients, and it can predict follicular density in women undergoing ovarian tissue cryopreservation.

Fertility preservation issues in pediatric hematopoietic stem cell transplantation: practical approaches from the consensus of the Pediatric Diseases Working Party of the EBMT and the International BFM Study Group

Fertility preservation is an urgent challenge in the transplant setting. A panel of transplanters and fertility specialists within the Pediatric Diseases Working Party of the European Society for Blood and Marrow Transplantation (EBMT) and the International BFM Study Group provides specific guidelines. Patients and families should be informed of possible gender- and age-specific cryopreservation strategies that should be tailored according to the underlying disease, clinical condition and previous exposure to chemotherapy. Semen collection should be routinely offered to all postpubertal boys at the diagnosis of any disease requiring therapy that could potentially impair fertility. Testicular tissue collection might be offered to postpubertal boys; nevertheless, its use has been unsuccessful to date. Oocyte collection after hormonal hyperstimulation should be offered to postpubertal girls facing gonadotoxic therapies that could be delayed for the 2 weeks required for the procedure. Ovarian tissue collection could be offered to pre-/post-pubertal girls. Pregnancies have been reported after postpubertal ovarian tissue reimplantation; however, to date, no pregnancy has been reported after the reimplantation of prepubertal ovarian tissue or in vitro maturation of pre-/post-pubertal ovarian tissue. Possible future advances in reproductive medicine could change this scenario. Health authorities should prioritize fertility preservation projects in pediatric transplantation to improve patient care and quality of life.

Update on fertility preservation from the Barcelona International Society for Fertility Preservation-ESHRE-ASRM 2015 expert meeting: indications, results and future perspectives

STUDY QUESTION

What progress has been made in fertility preservation (FP) over the last decade?

SUMMARY ANSWER

FP techniques have been widely adopted over the last decade and therefore the establishment of international registries on their short- and long-term outcomes is strongly recommended.

WHAT IS KNOWN ALREADY

FP is a fundamental issue for both males and females whose future fertility may be compromised. Reproductive capacity may be seriously affected by age, different medical conditions and also by treatments, especially those with gonadal toxicity. There is general consensus on the need to provide counselling about currently available FP options to all individuals wishing to preserve their fertility.

STUDY DESIGN, SIZE, DURATION

An international meeting with representatives from expert scientific societies involved in FP was held in Barcelona, Spain, in June 2015.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Twenty international FP experts belonging to the American Society of Reproductive Medicine, ESHRE and the International Society of Fertility Preservation reviewed the literature up to June 2015 to be discussed at the meeting, and approved the final manuscript. At the time this manuscript was being written, new evidence considered relevant for the debated topics was published, and was consequently included.

MAIN RESULTS AND THE ROLE OF CHANCE

Several oncological and non-oncological diseases may affect current or future fertility, either caused by the disease itself or the gonadotoxic treatment, and need an adequate FP approach. Women wishing to postpone maternity and transgender individuals before starting hormone therapy or undergoing surgery to remove/alter their reproductive organs should also be counselled accordingly. Embryo and oocyte cryopreservation are first-line FP methods in postpubertal women. Metaphase II oocyte cryopreservation (vitrification) is the preferred option. Cumulative evidence of restoration of ovarian function and spontaneous pregnancies after ART following orthotopic transplantation of cryopreserved ovarian tissue supports its future consideration as an open clinical application. Semen cryopreservation is the only established method for FP in men. Testicular tissue cryopreservation should be recommended in pre-pubertal boys even though fertility restoration strategies by autotransplantation of cryopreserved testicular tissue have not yet been tested for safe clinical use in humans. The establishment of international registries on the short- and long-term outcomes of FP techniques is strongly recommended.

LIMITATIONS, REASONS FOR CAUTION

Given the lack of studies in large cohorts or with a randomized design, the level of evidence for most of the evidence reviewed was 3 or below.

WIDER IMPLICATIONS OF THE FINDINGS

Further high quality studies are needed to study the long-term outcomes of FP techniques.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

N/A.

Current Success and Efficiency of Autologous Ovarian Transplantation: A Meta-Analysis

CONTEXT

Ovarian cryopreservation followed by autotransplantation is still considered an experimental strategy for fertility preservation (FP) mainly because the success rates are unknown.

OBJECTIVE

To determine cohort epidemiologic characteristics and success rates of autologous ovarian tissue transplantation (OTT) with previously cryopreserved tissue.

MATERIALS AND METHODS

Literature review from 1999 to October 1, 2016. Additional cases were retrieved from meeting abstracts and own database. We selected studies that reported autologous OTT with previously banked tissue in humans. We did not include any cases involving fresh ovarian tissue transplantation or those performed to treat idiopathic premature ovarian failure/insufficiency. Both authors reviewed and selected studies for eligibility, which resulted in 59 full-text studies assessed for eligibility. Cases were extracted from original reports and reviews by the junior author, and the senior author reviewed and verified the extracted data.

RESULTS

Nineteen reports were included for qualitative synthesis. In 10 studies, detailed data were available to determine clinical and live birth + ongoing (LB + OG) pregnancy as well as endocrine restoration rates. Three hundred nine OTTs were performed with cryopreserved tissue, resulting in the birth of 84 children and 8 OG pregnancies. The cumulative clinical and LB + OG rates were 57.5% and 37.7%, respectively, and the endocrine restoration rate was 63.9%.

CONCLUSION

Success rates with cryopreserved OTT have reached promising levels. Given these recent data, ovarian tissue cryopreservation should be considered as a viable option for FP.

Validation of an automated technique for ovarian cortex dissociation: isolation of viable ovarian cells and their qualification by multicolor flow cytometry

Background

Ovarian tissue cryopreservation is a technique for fertility preservation addressed to prepubertal girls or to patients for whom no ovarian stimulation is possible before initiation of gonadotoxic treatments. Autotransplantation of frozen-thawed ovarian tissue is the only available option for reuse but presents some limitations: ischemic tissue damages post-transplant and reintroduction of malignant cells in cases of cancer. It is therefore essential to qualify ovarian tissue before autograft on a functional and oncological point of view. Here, we aimed to isolate viable cells from human ovarian cortex in order to obtain an ovarian cell suspension analyzable by multicolor flow cytometry.

Methods

Ovarian tissue (fresh or frozen-thawed), from patients with polycystic ovarian syndrome (reference tissue) and from patients who underwent ovarian tissue cryopreservation, was used for dissociation with an automated device. Ovarian tissue-dissociated cells were analyzed by multicolor flow cytometry; the cell dissociation yield and viability were assessed. Two automated dissociation protocols (named laboratory and commercial protocols) were compared.

Results

The effectiveness of the dissociation was not significantly different between reference ovarian tissue (1.58 × 10⁶ ± 0.94 × 10⁶ viable ovarian cells per 100 mg of ovarian cortex, n = 60) and tissue from ovarian tissue cryopreservation (1.70 × 10⁶ ± 1.35 × 10⁶ viable ovarian cells, n = 18). However, the viability was slightly different for fresh ovarian cortex compared to frozen-thawed ovarian cortex whether we used reference tissue (p = 0.022) or tissue from ovarian cryopreservation (p = 0.018). Comparing laboratory and commercial protocols, it appeared that cell yield was similar but cell viability was significantly improved when using the commercial protocol (81.3% ± 12.3% vs 23.9% ± 12.5%).

Conclusion

Both dissociation protocols allow us to isolate more than one million viable cells per 100 mg of ovarian cortex, but the viability is higher when using the commercial dissociation kit. Ovarian cortex dissociation is a promising tool for human ovarian cell qualification and for ovarian residual disease detection by multicolor flow cytometry.

A review of reported surgical techniques in fertility preservation for prepubertal and adolescent females facing a fertility threatening diagnosis or treatment

BACKGROUND

Ovarian tissue cryopreservation is increasing as a preferred option for fertility preservation for prepubertal and young adolescent females facing a fertility threatening diagnosis or treatment.

DATA SOURCES

Ovid MEDLINE and PubMed searches for terms related to ovarian tissue removal for fertility preservation revealed there is no current consensus on operative technique for surgical ovarian cortical tissue removal in adult females. Additionally, there are limited published reports of surgical approach and outcomes in the pediatric population. In total, 22 publications were reviewed for their operative approach, ovarian tissue harvesting techniques, complications and outcomes.

CONCLUSIONS

Reported operative approaches and techniques for ovarian tissue cryopreservation for pediatric and adolescent patients are variable. Further investigations into operative technique and tissue harvesting that maintains healthy ovarian follicles for transplant will help establish standard technical principles for surgery in pediatric and adolescent females undergoing fertility preservation.

In vitro maturation of human immature oocytes for fertility preservation and research material

Aim

In recent years, the importance of fertility preservation (FP) has increased. In vitro maturation (IVM), an important technique in FP, has started to be used in the clinic, but controversies persist regarding this technique. Here, a survey of IVM for FP is provided.

Methods

Based on a literature review, the applications of FP, methods of FP, IVM of oocytes that had been collected in vivo and ex vivo, maturation of oocytes after IVM for FP, cryopreservation of oocytes for FP, explanation of the procedures to patients, and recent research on FP using IVM were investigated.

Results

Although IVM for FP remains controversial, the application of FP is expected to expand. Depending on the age and disease status of the patient, various methods of oocyte collection and ovarian stimulation, as well as various needle types and aspiration pressures, have been reported. The maturation rate of IVM in FP ranges widely and requires optimization in the future. In regard to cryopreservation for matured oocytes, the vitrification method is currently recommended.

Conclusion

Regarding FP for patients with cancer, the treatment of cancer is prioritized; thus, the time and use of medicines are often constrained. As several key points regarding IVM remain unclear, well‐designed and specific counseling for patients is necessary.

The promise of organ and tissue preservation to transform medicine

The ability to replace organs and tissues on demand could save or improve millions of lives each year globally and create public health benefits on par with curing cancer. Unmet needs for organ and tissue preservation place enormous logistical limitations on transplantation, regenerative medicine, drug discovery, and a variety of rapidly advancing areas spanning biomedicine. A growing coalition of researchers, clinicians, advocacy organizations, academic institutions, and other stakeholders has assembled to address the unmet need for preservation advances, outlining remaining challenges and identifying areas of underinvestment and untapped opportunities. Meanwhile, recent discoveries provide proofs of principle for breakthroughs in a family of research areas surrounding biopreservation. These developments indicate that a new paradigm, integrating multiple existing preservation approaches and new technologies that have flourished in the past 10 years, could transform preservation research. Capitalizing on these opportunities will require engagement across many research areas and stakeholder groups. A coordinated effort is needed to expedite preservation advances that can transform several areas of medicine and medical science.