Fertility preservation: successful transplantation of cryopreserved ovarian tissue in a young patient previously treated for Hodgkin's disease

Fertility preservation in patients undergoing gonadotoxic treatments: a Canadian Fertility and Andrology Society clinical practice guideline

The management of young patients with cancer presents several unique challenges. In general, these patients are ill prepared for the diagnosis and the impact on their fertility. With the improved survival for all tumour types and stages, the need for adequate fertility counselling and a multidisciplinary approach in the reproductive care of these patients is paramount. Recent advances in cryopreservation techniques allow for the banking of spermatozoa, oocytes, embryos and ovarian tissue without compromising survival. This Canadian Fertility and Andrology Society (CFAS) guideline outlines the current understanding of social and medical issues associated with oncofertility, and the medical and surgical technologies available to optimize future fertility.

Perinatal outcomes of pregnancies following autologous cryopreserved ovarian tissue transplantation: a systematic review with pooled analysis

OBJECTIVE

This study aimed to synthesize the existing evidence on perinatal outcomes after autologous cryopreserved ovarian tissue transplantation, concurrently identifying key factors influencing these outcomes.

DATA SOURCES

A comprehensive search was performed on MEDLINE, Embase, and Cochrane Library databases to identify relevant studies on the effect of autologous cryopreserved ovarian tissue transplantation on perinatal outcomes from inception to October 22, 2023. Where there was missing information, the authors were contacted for updated data.

STUDY ELIGIBILITY CRITERIA

Observational studies, such as cohort studies, case series, and case reports that reported a live birth after autologous cryopreserved ovarian tissue transplantation, were considered eligible. Studies lacking data on women's demographic characteristics, autologous cryopreserved ovarian tissue transplantation procedure details, or perinatal outcomes were excluded. In addition, cases involving fresh or nonautologous transplantations and those addressing primary ovarian insufficiency were excluded.

METHODS

Two reviewers (M.E. and E.U.) independently performed the study selection, data extraction, and risk of bias assessment, and the results were then reviewed together. The PRISMA guidelines were followed, and the protocol was registered on PROSPERO (CRD42023469296).

RESULTS

This review included 58 studies composed of 122 women with 162 deliveries (154 singletons and 8 twins) after autologous cryopreserved ovarian tissue transplantation, resulting in 170 newborns. Of note, 83.6% of the women had a malignant disease. Moreover, most of these women (51.0%) were exposed to some form of chemotherapy before ovarian tissue cryopreservation. Of the 162 childbirths, 108 (66.7%) were conceived naturally, and 54 (33.3%) were conceived through assisted reproductive techniques. The birthweight of 88.5% of newborns was appropriate for gestational age, whereas 8.3% and 3.1% were small for gestational age and large for gestational age, respectively. The preterm birth rate was 9.4%, with the remaining being term deliveries. Hypertensive disorders of pregnancy were noted in 18.9% of women, including pregnancy-induced hypertension in 7.6%, preeclampsia in 9.4%, and hemolysis, elevated liver enzymes, and low platelet count in 1.9%. The incidences of gestational diabetes mellitus and preterm premature rupture of membranes were 3.8% for each condition. Neonatal anomalies were reported in 3 transplant recipients with 4 newborns: arthrogryposis, congenital cataract, and diaphragmatic hernia in a twin. Finally, among the recipients' characteristics, not receiving chemotherapy before ovarian tissue cryopreservation (odds ratio, 0.23; 95% confidence interval, 0.07-0.72; P=.012) and natural conception (odds ratio, 0.29; 95% confidence interval, 0.09-0.92; P=.035) were associated with a lower perinatal complication rate.

CONCLUSION

On the basis of low certainty evidence from observational studies, perinatal complication rates did not increase after autologous cryopreserved ovarian tissue transplantation compared with the general pregnant population, except for preeclampsia. This could be due to chemotherapy exposure, underlying medical conditions, and the common use of assisted reproductive techniques. Further larger studies are needed to explore the causes of increased preeclampsia incidence in autologous cryopreserved ovarian tissue transplantation pregnancies.

Effects of Ovarian Tissue Cryopreservation on Primary Ovarian Insufficiency in Girls Undergoing Bone Marrow Transplantation

OBJECTIVE

To determine if removing an ovary for ovarian tissue cryopreservation (OTC) increased rates of primary ovarian insufficiency (POI) in girls undergoing bone marrow transplantation (BMT). Institutional review board approval was obtained from all 3 clinical sites.

DESIGN

Multicenter retrospective cohort study SETTING: Academic children's hospitals PATIENTS: Females aged 2-21 who underwent BMT with or without OTC from 2010 to 2017.

INTERVENTIONS

None MAIN OUTCOME MEASURES: Rates of POI in girls who underwent OTC vs those who underwent BMT alone as determined by serum markers, presence of menses, or clinical diagnosis.

RESULTS

A total of 142 patients were identified, 43 who had OTC and 99 with BMT alone. The rate of POI in girls undergoing OTC was 65% vs 41.8% in those who underwent BMT alone (P = .26).

CONCLUSIONS

Although this study was not powered to detect a lack of difference, it is reassuring that there does not seem to be a clinically significant increase in POI in patients undergoing OTC.

Ovarian Tissue Cryopreservation in Children and Adolescents

Cancer during childhood and adolescence remains a major public health issue, affecting a significant portion of this age group. Although newer anti-cancer treatments have improved survival rates, this comes at a cost in terms of gonadotoxic effects. As a result, the preservation of fertility is important. Ovarian tissue cryopreservation, one of the newest methods, has some advantages, especially for prepubertal patients: no need for ovarian stimulation, thus, no further risk for estrogen-sensitive cancer types, and preservation of more and better-quality primordial follicles of the ovarian cortex. The most frequent indications include treatment with alkylating agents, ovarian-focused radiotherapy, leukemias, lymphomas, brain and neurological tumors, as well as Turner syndrome and benign hemoglobinopathies. An expected survival exceeding 5 years, the absence of systematic disease and an overall risk of premature ovarian insufficiency over 50% are among the criteria that need to be fulfilled in order for a patient to undertake this method. Orthotopic transplantation is more frequently used, since it can allow both live birth and the recovery of endocrine function. Reimplantation of malignant cells is always a major risk and should always be taken into consideration. Histological analysis, as well as immunohistochemical and molecular methods, are needed in order to improve the search for malignant cells before transplantation. Ovarian tissue cryopreservation appears to be a method with specific benefits, indications and risks which can be an important tool in terms of preserving fertility in younger women.

Preserving Oocytes in Oncofertility†

The prodigious rise of cancer survival rates enables many cancer survivors to live long lives. Therefore, the side effects of cancer treatments as well as the long-term quality of life after cancer have become more relevant. Ovarian toxicity is a major off-target effect of anticancer agents for childhood and young adult female cancer patients. Both chemotherapy and irradiation have been demonstrated to damage the ovary and increase the risks of premature ovarian failure (POF), early menopause, ovarian endocrine disorders, and sub- or infertility. Oncofertility is an emerging and multidisciplinary research and medical field that focuses on providing cancer patients with fertility preservation options. Oocyte quality and quantity are one of the most important factors to determine women's fertility success; therefore, preserving oocytes is paramount for maintaining the ability of young female cancer patients' reproduction after their recovery. This review summarizes peer-reviewed literature on current oocyte preservation options in oncofertility. We describe in-depth oocyte and embryo cryopreservation, ovarian suppression, ovarian tissue cryopreservation, in vitro maturation, ovarian transposition, and adjuvant therapy. Further, we discuss current guidelines and practices of female fertility preservation that cover preserving oocytes.

Promotion of angiogenesis toward transplanted ovaries using nitric oxide releasing nanoparticles in fibrin hydrogel

Transplantation of ovary is one method of facilitating fertility preservation to increase the quality of life of cancer survivors. Immediately after transplantation, ovaries are under ischemic conditions owing to a lack of vascular anastomosis between the graft and host tissues. The transplanted ovaries can suffer damage because of lack of oxygen and nutrients, resulting in necrosis and dysfunction. In the technique proposed in this paper, the ovary is encapsulated with nitric oxide-releasing nanoparticles (NO-NPs) in fibrin hydrogels, which form a carrying matrix to prevent ischemic damage and accelerate angiogenesis. The low concentration of NO released from mPEG-PLGA nanoparticles elicits blood vessel formation, which allows transplanted ovaries in the subcutis to recover from the ischemic period. In experiments with mice, the NO-NPs/fibrin hydrogel improved the total number and quality of ovarian follicles after transplantation. The intra-ovarian vascular density was 4.78 folds higher for the NO-NPs/fibrin hydrogel groups compared to that for the nontreated groups. Finally,in vitrofertilization revealed a successful blastocyst formation rate for NO-NPs/fibrin hydrogel coated ovaries. Thus, NO-NPs/fibrin hydrogels can provide an appropriate milieu to promote angiogenesis and be considered as adjuvant surgery materials for fertility preservation.

Two-Decade Experience of Royan Institute in Obtaining Mature Oocyte from Cryopreserved Ovarian Tissue: In Vitro and In Vivo Approaches

Ovarian tissue cryopreservation (OTC) holds promise for preservation of fertility among women who have lost their fertility due to diseases such as cancer. OTC has significantly assisted such cases by helping them maintain normal hormonal levels and menstrual cycles. Appropriate strategies to develop and extract mature oocytes from OTC could overcome a range of complications that are associated with ovarian dysfunction, caused by aging, and primary or secondary ovarian insufficiency. Scientists from different departments at The Royan Institute (Tehran, Iran) have been conducting studies to find the best way to extract mature oocytes from animal and human cryopreserved ovarian tissues. The various studies conducted in this area in the past 20 years, by researchers of the Royan Institute, are collated and provided in this review, in order to provide an idea of where we are now in the area of fertility preservation.

Novel Approaches in Addressing Ovarian Insufficiency in 2019: Are We There Yet?

Ovarian insufficiency is described as a multifaceted issue typically encountered in the field of assisted reproduction. The three main identified diagnoses of ovarian insufficiency include premature ovarian failure (POF), poor ovarian response (POR), and advanced maternal age (AMA). Patient heterogeneity in the era of individualized medicine drives research forward leading to the emergence of novel approaches. This plethora of innovative treatments in the service of adequately managing ovarian insufficiency is called to undertake the challenge of addressing infertile patients exploring their reproductive options. This review provides an all-inclusive presentation and critical analysis on novel treatments that have not achieved routine clinical practice status yet, but have recently emerged as promising. In light of the lack of randomized controlled trials conveying safety and efficiency, clinicians are left puzzled in addressing the "how" and "for whom" these approaches may be beneficial. From ovarian injection employing platelet-rich plasma (PRP) or stem cells to artificial gametes and ovaries, ovarian transplantation, and mitochondrial replacement therapy, this descriptive review provides insight toward assisting the practitioner in decision making regarding these cutting-edge treatments. Biological mechanisms, invasiveness levels, efficiency, as well as possible complications, the current status along with bioethical concerns are discussed in the context of identifying future optimal treatment.

Comparison between two cryopreservation techniques of human ovarian cortex: morphological aspects and the heat shock response (HSR)

This study was tailored to compare the cryopreservation of the human ovarian cortex using closed metal container vitrification or the slow-freezing technique. Superficial ovarian cortical tissue biopsies were collected from 12 participants who underwent gynaecological videolaparoscopy. The fragmented samples were allocated to three experimental conditions: (a) fresh ovarian tissue, (b) slow-freezing, and (c) vitrification with a metal closed container. After thawing or rewarming, cellular morphological analyses were performed to determine tissue viability. The cellular response to thermal stress was measured by a putative increase in the immune quantification of the heat shock protein 70 kDa (heat shock protein 70 kDa response - HSR) after a heat challenge (2 h exposure at 42 °C). Both the total number of intact follicles and the frequency of primordial follicles were higher in fresh ovarian tissue than in the preserved samples, regardless of the technique employed. There was a trend towards an increase in the absolute number of intact follicles in the tissue preserved by vitrification. After cryopreservation, a higher HSR was obtained after slow-freezing. These results indicate that both cryopreservation techniques present advantages and may be used as alternatives to ovarian tissue cryopreservation.

Practical consensus recommendations on fertility preservation in patients with breast cancer

Young women diagnosed with cancer today have a greater chance of long-term survival than ever before. Successful survivorship for this group of patients includes maintaining a high quality of life after a cancer diagnosis and treatment; however, lifesaving treatments such as chemotherapy, radiation, and surgery can impact survivors by impairing reproductive and endocrine health. Expert oncologists along with reproductive medicine specialists discuss fertility preservation options in this chapter since fertility preservation is becoming a priority for young women with breast cancer. This expert group used data from published literature, practical experience and opinion of a large group of academic oncologists to arrive at these practical consensus recommendations for the benefit of community oncologists.

Implications of Nonphysiological Ovarian Primordial Follicle Activation for Fertility Preservation

In recent years, ovarian tissue cryopreservation has rapidly developed as a successful method for preserving the fertility of girls and young women with cancer or benign conditions requiring gonadotoxic therapy, and is now becoming widely recognized as an effective alternative to oocyte and embryo freezing when not feasible. Primordial follicles are the most abundant population of follicles in the ovary, and their relatively quiescent metabolism makes them more resistant to cryoinjury. This dormant pool represents a key target for fertility preservation strategies as a resource for generating high-quality oocytes. However, development of mature, competent oocytes derived from primordial follicles is challenging, particularly in larger mammals. One of the main barriers is the substantial knowledge gap regarding the regulation of the balance between dormancy and activation of primordial follicles to initiate their growing phase. In addition, experimental and clinical factors also affect dormant follicle demise, while the mechanisms involved remain largely to be elucidated. Moreover, most of our basic knowledge of these processes comes from rodent studies and should be extrapolated to humans with caution, considering the differences between species in the reproductive field. Overcoming these obstacles is essential to improving both the quantity and the quality of mature oocytes available for further fertilization, and may have valuable biological and clinical applications, especially in fertility preservation procedures. This review provides an update on current knowledge of mammalian primordial follicle activation under both physiological and nonphysiological conditions, and discusses implications for fertility preservation and priorities for future research.

Whole Ovary Cryopreservation and Transplantation: A Systematic Review of Challenges and Research Developments in Animal Experiments and Humans

Ovarian tissue cryopreservation and transplantation is the only fertility preservation option that enables both restoration of fertility and resumption of ovarian endocrine function, avoiding the morbidity associated with premature menopause. It is also the only technique available to prepubertal patients and those whose treatment cannot be delayed for life-threatening reasons. Ovarian tissue cryopreservation can be carried out in two different ways, either as ovarian cortical fragments or as a whole organ with its vascular pedicle. Although use of cortical strips is the only procedure that has been approved by the American Society for Reproductive Medicine, it is fraught with drawbacks, the major one being serious follicle loss occurring after avascular transplantation due to prolonged warm ischemia. Whole ovary cryopreservation involves vascular transplantation, which could theoretically counteract the latter phenomenon and markedly improve follicle survival. In theory, this technique should maintain endocrine and reproductive functions much longer than grafting of ovarian cortical fragments. However, this procedure includes a number of critical steps related to (A) the level of surgical expertise required to accomplish retrieval of a whole ovary with its vascular pedicle, (B) the choice of cryopreservation technique for freezing of the intact organ, and (C) successful execution of functional vascular reanastomosis upon thawing. The aim of this systematic review is to shed light on these challenges and summarize solutions that have been proposed so far in animal experiments and humans in the field of whole ovary cryopreservation and transplantation.

Human Ovarian Cortex biobanking: A Fascinating Resource for Fertility Preservation in Cancer

Novel anti-cancer treatments have improved the survival rates of female young patients, reopening pregnancy issues for female cancer survivors affected by the tumor treatment-related infertility. This condition occurs in approximately one third of women of fertile age and is mainly dependent on gonadotoxic protocols, including radiation treatments. Besides routine procedures such as the hormonal induction of follicular growth and subsequent cryopreservation of oocytes or embryos, the ovarian protection by gonadotropin-releasing hormone (GnRH) agonists during chemotherapy as well as even gonadal shielding during radiotherapy, other innovative techniques are available today and need to be optimized to support their introduction into the clinical practice. These novel methods are hormone stimulation-free and include the ovarian cortex cryopreservation before anti-cancer treatments and its subsequent autologous reimplantation and a regenerative medicine approach using oocytes derived in vitro from ovarian stem cells (OSCs). For both procedures, the major benefit is related to the prompt recruitment and processing of the ovarian cortex fragments before gonadotoxic treatments. However, while the functional competence of oocytes within the cryopreserved cortex is not assessable, the in vitro maturation of OSCs to oocytes, allows to select the most competent eggs to be cryopreserved for fertility restoration.

Vitrification technique for female germinative tissue cryopreservation and banking

Objective

To report on a device designed for the vitrification of germinative tissue, and a systematic vitrification/warming protocol.

Methods

We obtained six fragments of cortical germinative tissue from a human ovary. We randomly chose two fragments and sent them to histological analysis. We vitrified four test samples and stored them for one week in liquid nitrogen (LN), and warmed one week later. We sent the vitrified/warmed fragments to the pathology laboratory, where they analyzed them morphologically under an optical microscope (10-40X). They analyzed the nuclear and cytoplasmic characteristics of the follicular cells, luteal layer, and stroma. The primordial and primary follicles in the fresh and vitrified/warmed fragments were counted and compared with the Mann-Whitney test (p<0.05).

Results

There were ovarian follicles in different phases of maturation in both fresh and vitrified/warmed fragments, with a predominance of healthy-looking primordial and primary follicles. In the test fragments, the fusocellular architecture supporting the stromal cells exhibited some foci of edema, and were associated with cells with hydropic degeneration, with cytoplasmic fragmentation and eosinophilia. However, there were no signs of tissue necrosis or autolysis. There was no statistically significant difference between the number of follicles found in the control and test tissue fragments (p>0.05).

Conclusions

There were no significant morphological changes between fresh and vitrified/warmed germinative tissue. The vitrification device and protocol tested were effective in the preservation of human follicles, and should be considered for the banking germinative tissue for the restoration of fertility of women who are submitted to life-saving sterilizing treatments.

Heterotopic transplantation of cryopreserved ovarian tissue in cancer patients: a case series

Transplantation of cryopreserved ovarian tissue offers patients a chance to preserve fertility during cancer treatment. In this study of ten young women with gynecological cancer, heterotopic sites were tested for serum hormones and follicle growth to estimate transplant longevity and prospects for assisted conception. Frozen-thawed grafts were implanted subcutaneously in the forearm (FA) (2 cases), the abdominal wall (AW) (11 cases), and the peritoneal lining (P) (3 cases) . In the follow-up of 36 months, a total of 80 ovarian cycles in different heterotopic sites were analyzed. FA and AW grafts had wildly fluctuating FSH, while estradiol (E2) reached preovulatory levels only in AW and P grafts. Follicular growth was active in P sites (1.2 ± 0.1 mm/d) and sluggish in FA and AW sites (0.4 ± 0.1 mm/d). A mature oocyte was only retrieved from the AW, while seven other aspirations were unsuccessful. Meanwhile, a patient delivered twice after treatment for Hodgkin's lymphoma when orthotopic transplantation was performed, first from an IVF cycle and subsequently from a natural cycle. In conclusion, these findings offer no strong encouragement for fertility preservation by transplanting cryopreserved ovarian tissue to subcutaneous sites, and although the peritoneal site gave better results, graft longevity averaged the same at around 3 years.

Reproductive outcomes following a stem cell transplant for a haematological malignancy in female cancer survivors: a systematic review and meta-analysis

PURPOSE

The use of high-dose chemotherapy and radiotherapy combined with haematopoietic stem cell transplantation (HSCT) may negatively affect a woman's reproductive potential. Reproductive outcomes such as infertility are a major concern for women who undergo treatment for a haematological cancer diagnosis.

OBJECTIVE

This systematic review and meta-analysis explores reproductive outcomes following a haematological cancer requiring HSCT.

METHODS

Electronic databases were searched to identify studies that reported on reproductive outcomes after treatment for a haematological cancer diagnosis. Studies were included that reported on pregnancy and reproductive outcomes following HSCT for a haematological malignancy.

RESULTS

The meta-analysis included 14 studies, collectively involving 744 female patients. The subgroup analysis showed an overall pooled estimated pregnancy rate, for autologous or allogeneic HSCT recipients, of 22.7% (n = 438). There were 25% (n = 240) of women who became pregnant after autologous HSCT compared with 22% (n = 198) who subsequently became pregnant following allogeneic HSCT.

CONCLUSIONS

This meta-analysis reflects low pregnancy rates for cancer survivors desiring a family. However, live births are improving over time with new technology and novel therapies. Hence, female cancer patients should be offered timely discussions, counselling and education around fertility preservation options prior to starting treatment with gonadotoxic therapy.

Current state and future possibilities of ovarian tissue transplantation

BACKGROUND

As a result of recent developments in cancer treatment, cancer survivorship and survivors' quality of life have been emphasized. Although ovarian tissue cryopreservation (OTC) is an experimental technique, it would be the sole technique for fertility preservation treatment for girls with malignant disease. Indeed, OTC requires ovarian tissue transplantation (OTT) for conception. As for OTC, there is room to investigate OTT. The present review focused on the current state and progress of OTT.

METHOD

The literature regarding OTT, which is currently under development, was reviewed.

MAIN FINDINGS

To improve the outcome of OTT, both efficacy and safety are important. Good surgical technique and the optimal site are important surgical factors, with orthotopic transplantation increasing. Treatment of growth factors, gonadotropins, antioxidants, apoptosis suppression factors, and cell therapy may improve the efficacy of OTT by inducing neo-angiogenesis and preventing damage. Artificial ovaries, complete in vitro primordial follicle culture technique, and non-invasive ovarian imaging techniques, such as optical coherence tomography, to select the best ovarian tissue are future possibilities.

CONCLUSION

Improving neo-angiogenesis and preventing damage with optimization, as well as investigation of future techniques, may bring us to the next stage of a fertility preservation strategy.

Cryopreservation of Human Ovarian Tissue: A Review

BACKGROUND

Cryopreservation of human ovarian tissue has been increasingly applied worldwide to safeguard fertility in cancer patients, notably in young girls and women who cannot delay the onset of their treatment. Moreover, it has been proposed to patients with benign pathologies with a risk of premature ovarian insufficiency. So far, more than 130 live births have been reported after transplantation of cryopreserved ovarian tissue, and almost all patients recovered their ovarian function after tissue reimplantation.

SUMMARY

This review aims to summarize the recent results described in the literature regarding human ovarian tissue cryopreservation in terms of methods and main results obtained so far. To cryopreserve human ovarian tissue, most studies describe a slow freezing/rapid thawing protocol, which is usually an adaptation of a protocol developed for sheep ovarian tissue. Since freezing has been shown to have a deleterious effect on ovarian stroma and granulosa cells, various research groups have been vitrifying ovarian tissue. Despite promising results, only 2 babies have been born after transplantation of vitrified/warmed ovarian tissue. Optimization of both cryopreservation strategies as well as thawing/warming protocols is therefore necessary to improve the survival of follicles in cryopreserved ovarian tissue.

KEY MESSAGES

Human ovarian tissue cryopreservation has been successfully applied worldwide to preserve fertility in patients with malignant or nonmalignant pathologies that have a detrimental effect on fertility. Human ovarian tissue cryopreservation could also be applied as an alternative to postpone pregnancy or menopause in healthy women. Slow freezing and vitrification procedures have been applied to cryopreserve human ovarian tissue, but both alternatives require optimization.

Pyroptosis is involved in cryopreservation and auto-transplantation of mouse ovarian tissues and pyroptosis inhibition improves ovarian graft function

The aim of this study was to investigate the role of pyroptosis in the cryopreservation and transplantation of mouse ovarian tissues; the effects of pyroptosis inhibitior on the ovarian graft function were also explored. ICR (institute of cancer research) mice were randomly divided into control group and experimental groups (n = 10 per group). The experimental groups included fresh graft group (autograft), cryopreserved graft group (cryopreservation + autograft), and pyroptosis inhibition group (cryopreservation + autograft + pyroptosis inhibitor). At the third day after auto-transplantation, caspase-1 and NLRP3 protein expression in grafts were assessed by Western blot; in the meantime, serum concentration of IL-1β was examined by ELISA. After 28 days of auto-transplantation, estradiol concentrations and follicular densities of grafts were evaluated. The caspase-1 and NLRP3 protein expression in grafts from all the experimental groups were significantly higher than that from control group respectively; moreover, there was a significant increase in serum concentrations of IL-1β in all experimental groups compared with control group. The concentration of estradiol and follicular densities of grafts in pyroptosis inhibition group were significantly higher than that in cryopreserved graft group. Pyroptosis is involved in cryopreservation and auto-transplantation of mouse ovarian tissues, and pyroptosis inhibition can improve the ovarian graft function.

Reproductive Outcomes After a Childhood and Adolescent Young Adult Cancer Diagnosis in Female Cancer Survivors: A Systematic Review and Meta-analysis

Improvements in cancer therapy for childhood and adolescent and young adult (AYA) survivors have increased in excess of 80% among pediatric patients and in excess of 85% among AYA cancer patients. Our research group explored the late effects consequences of cancer treatment on pregnancy and birth outcomes subsequent to a childhood (0-14 years) or AYA (15-25 years) diagnosis of cancer in female cancer survivors. Embase and Medline databases were searched. There were 17 review (n = 10 matched and n = 7 unmatched) studies that met the inclusion criteria. Subanalyses were conducted on 10 matched studies. The median age for all studies for patients at diagnosis and birth was 11 and 27 years, respectively. In matched cohort studies, female childhood and AYA cancer patients, who received chemotherapy alone, had a pooled estimated rate of 18% of experiencing a live birth compared with 10% of females who received radiotherapy alone and subsequently had a live birth. Females who received surgery alone reported higher pooled estimated rates of 44% for a live birth. For matched retrospective review studies, 79% (n = 973) of women experienced a live birth, of which 22% of these babies were born preterm. This meta-analysis found lower birth rates for survivors. Access to fertility-related information and discussions around fertility preservation options and oncofertility psychosocial support should be offered to all cancer patients and their families before starting cancer treatment.

Contemporarily Treated Patients With Hodgkin Lymphoma Have Childbearing Potential in Line With Matched Comparators

Purpose With excellent cure rates for young patients with Hodgkin lymphoma (HL), there is an increasing number of female survivors of HL interested in becoming pregnant. Here, we report childbearing among contemporarily treated HL survivors in comparison with the general population. Material and Methods Using Swedish registers, 449 women (ages 18 to 40 years) diagnosed with HL between 1992 and 2009 and in remission 9 months after diagnosis were identified. Patients were age- and calendar-year-matched to 2,210 population comparators. Rates of first postdiagnosis childbirth were calculated. Hazard ratios (HRs) with 95% CIs were estimated for different follow-up periods using Cox regression. Cumulative probabilities of first childbirth were calculated in the presence of the competing risk of death or relapse. Results Twenty-two percent of relapse-free patients with HL had a child during follow-up, and first childbirth rates increased over time, from 40.2 per 1,000 person-years (1992 to 1997) to 69.7 per 1,000 person-years (2004 to 2009). For comparators, childbirth rates remained stable (70.1 per 1,000 person-years). Patients diagnosed between 2004 and 2009 had a cumulative probability of childbirth similar to comparators. Three years or more after diagnosis, no differences in childbirth rates were observed between patients and comparators, regardless of stage or treatment. Patients who received six to eight courses of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone had a lower childbirth rate than comparators during the first 3 years (HR, 0.23; 95% CI, 0.06 to 0.94), as did patients who received six to eight courses of chemotherapy and radiotherapy (HR, 0.21; 95% CI, 0.07 to 0.65). Conclusion Childbearing potential among female survivors of HL has improved over time, and childbirth rates 3 years after diagnosis in contemporarily treated patients are, in the absence of relapse, similar to those in the general population, regardless of stage and treatment.

Ovarian tissue cryopreservation and transplantation in patients with cancer

Chemotherapy and radiotherapy improved survival rates of patients with cancer. However, they can cause ovarian failure and infertility in women of reproductive age. Infertility following cancer treatment is considered a major quality of life issue. Ovarian tissue cryopreservation and transplantation is an important option for fertility preservation in adult patients with cancer who need immediate chemotherapy or do not want to undergo ovarian stimulation. Ovarian tissue freezing is the only option for preserving the fertility of prepubertal patients with cancer. In a recent review, it was reported that frozen-thawed ovarian transplantation has lead to about 90 live births and the conception rate was about 30%. Endocrine function recovery was observed in 92.9% between 3.5 and 6.5 months after transplantation. Based on our review, ovarian tissue cryopreservation and transplantation may be carefully considered before cancer treatment in order to preserve fertility and endocrine function in young cancer survivors.

Transplantation of frozen-thawed ovarian tissue: an update on worldwide activity published in peer-reviewed papers and on the Danish cohort

PURPOSE

The purpose of the study is to review all peer-reviewed published reports of women receiving ovarian tissue transplantation (OTT) with frozen/thawed tissue (OTC) with respect to age, diagnosis, transplantation site, fertility outcome, and potential side effects, including data from all women in the Danish program.

METHODS

A systematic review of the literature was performed in PubMed combined with results from all patients who had received OTT in Denmark up to December 2017.

RESULTS

OTT has been reported from 21 different countries comprising a total of 360 OTT procedures in 318 women. In nine women, malignancy was diagnosed after OTT; none were considered to be directly caused by the OTT. Despite a potential under reporting of cancer recurrence, there is currently no evidence to suggest that OTT causes reseeding of the original cancer. Renewed ovarian endocrine function was reported in 95% of the women. Half of all children born following OTT resulted from natural conception, and newborns were reported to be healthy except for one neonate with a chromosome anomaly with a family disposition. Women who conceived after OTT were significantly younger than those who failed.

CONCLUSION

This study found no indications of sufficient numbers of malignant cells present in the ovarian tissue to cause recurrence of cancer after OTT. Further, it is unlikely that OTC affects the well-being of children born. OTC is now an established method of fertility preservation in Denmark with public reimbursement. The current data encourage that women who require gonadotoxic treatment should be offered an individual evaluation considering fertility preservation.

Fertility protection: complications of surgery and results of removal and transplantation of ovarian tissue

Fertility-preserving measures are becoming important for patients receiving oncological treatment. One method involves cryopreservation of ovarian tissue and transplanting it when treatment is completed. We report complications resulting from surgical and fertility medicine, and the results of procedures for the removal and transplantation of ovarian tissue carried out within the FertiProtekt network. A survey using a structured questionnaire was conducted among the FertiProtekt network centres between November 2015 and June 2016. The analysis included surgical techniques used to remove and transplant ovarian tissue, surgical complications and results. Laparoscopic removal and transplantation of ovarian tissue have a low risk of complications. Surgical complications occurred in three of the network's 1373 ovarian tissue removals (n = 1302) and transplantations (n = 71); two complications (0.2%) occurred during removal and one during transplantation. Menstruation resumed in 47 out of 58 women (81%) who underwent ovarian tissue transplantation. Hormonal activity occurred in 63.2% of transplantations with a follow-up of 6 months or over. Sixteen pregnancies occurred in 14 patients, with nine births. The risks and complications of removal and transplantation of ovarian tissue are similar to those of standard laparoscopy. These procedures are becoming standard for fertility protection in cancer patients.

Cryopreservation of human ovarian tissue using the silver closed vitrification system

PURPOSE

The aim of this study is to evaluate the feasibility of using a hand-made silver container for the cryopreservation of human ovarian cortex.

METHODS

Human ovarian cortex tissues were vitrified using an open vitrification system (OVS) of needle immersed vitrification (NIV) and two closed vitrification systems (CVS) of a plastic vial (plastic CVS) and a silver container (silver CVS). Outcomes of vitrification were evaluated morphologically and histologically by in vitro culture and xenotransplantation. The apoptosis of primordial follicles was assessed by TUNEL staining. The production of E2 and P4 was examined by a chemiluminescent immunoassay. Blood vessels were visualized with CD31 staining.

RESULTS

Compared with the fresh ovarian cortex tissue, ovarian cortex tissues that were vitrified using the three different carriers and then warmed showed significantly reduced percentages of normal primordial follicles, viability of primordial follicles, E2 and P4 levels during in vitro culture and decreased amounts of blood vessels. However, much better outcomes were obtained with NIV and silver CVS than with plastic CVS, based on the better morphology and viability of primordial follicles, higher E2 and P4 production during an in vitro culture, and greater numbers of blood vessels after xenografting. Importantly, the outcomes of ovarian cortex cryopreservation with silver CVS were similar and comparable to those with NIV.

CONCLUSIONS

The hand-made silver container as a CVS is a promising carrier for the cryopreservation of the human ovarian cortex.

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.

Viability of homologous and heterologous subcutaneous transplantation of fresh germ cells in rabbits

OBJECTIVE

This study aimed to compare heterologous to homologous transplantation of fresh ovarian germ cells in rabbits.

METHODS

Twelve female white New Zealand rabbits (Oryctolagus cuniculus) were randomly numbered and submitted to bilateral oophorectomies. The ovaries from the six odd-numbered rabbits were dissected and cortical germinal tissue was digested in collagenase type 1 to obtain six solutions containing stromal and germ cells, which were injected in the abdominal region of the odd-numbered rabbits themselves (homologous transplantation) and of the even-numbered rabbits (heterologous transplantation) off immunosuppression. Sixty days after transplantation, the tissue around the transplanted region was excised, processed and sent to histological analysis with hematoxylin-eosin staining and Bcl-2 immunohistochemistry to verify the presence and viability of the transplanted cells.

RESULTS

The analyzed specimens contained ovarian stroma, while follicular cells were found in 66.6% of the homologous and in 60% of the heterologous transplant specimens. Mild inflammatory reaction was observed in all heterologous specimens, and in only one (16.7%) of the homologous specimens. However, this inflammatory reaction was not so intense as to cause the death of the implanted cells. Except for the specimens from rabbits 7 and 8, all specimens were stained for Bcl-2, indicating that most of them were viable.

CONCLUSIONS

The results of this study supported the viability of heterologous transplantation of fresh ovarian germ cells. However, more studies are required to further our understanding and improve the germ cell separation technique.

Operative techniques and complications of extraction and transplantation of ovarian tissue: the Erlangen experience

PURPOSE

Extracting ovarian tissue before oncologic therapy and transplanting it afterwards are increasingly being used to preserve fertility in women. This study describes standardized and safe operative procedures, with few complications, and reports the resulting ovarian function and pregnancy rates.

METHODS

The standardized operative techniques for removing and transplanting ovarian tissue used at the Erlangen center are: for tissue removal, one-third to half of the tissue from one ovary is excised with scissors, without tissue coagulation; for subsequent transplantation, pieces of ovarian tissue are placed in a retroperitoneal pocket without closure of the pocket.

RESULTS

Between January 2007 and December 2015, ovarian tissue was extracted in 399 women and transplanted following cancer therapy in 38. No surgical complications were observed within 28 days. To date, there have been ten pregnancies and nine live births after transplantation in seven different women; 26 of the 38 women developed hormonal activity, confirmed by a menstrual cycle or raised serum estradiol levels.

CONCLUSIONS

The techniques for laparoscopic removal and transplantation of ovarian tissue described here provide a standardized method with a very low risk of complications. The pregnancy rate after ovarian tissue transplantation, currently 15-30%, can be expected to rise further in the near future.

86 successful births and 9 ongoing pregnancies worldwide in women transplanted with frozen-thawed ovarian tissue: focus on birth and perinatal outcome in 40 of these children

PURPOSE

This study aims to make an account of the children born following transplantation of frozen-thawed ovarian tissue worldwide with specific focus on the perinatal outcome of the children. Furthermore, perinatal outcome of seven deliveries (nine children) from Denmark is reported.

METHODS

PubMed was searched for papers of deliveries resulting from ovarian tissue cryopreservation (OTC). Seven women underwent OTC prior to chemotherapy. Four of these women still had low ovarian function and had tried to conceive. They therefore had tissue autotransplanted to augment their fertility. The other three women had developed premature ovarian insufficiency (POI) after the end of treatment.

RESULTS

Worldwide, approximately 95 children have been born or will be born in the near future from OTC, including these 9 new children. Information on the perinatal outcome was found on 40 children. The mean gestational age was 39 weeks and the mean birth weight was 3168 g of the singleton pregnancies, which is within internationally recognized normal standards. Furthermore, half the singletons resulted from natural conception and all twins resulted from in vitro fertilization treatment. All seven Danish women became pregnant within 1-3 years after transplantation. They gave birth to nine healthy children.

CONCLUSION

The data is reassuring and further suggests that cryopreservation of ovarian tissue is becoming an established fertility preservation method. The seven Danish women reported in this study were all in their early thirties when OTC was performed. Most other reported cases were in the women's twenties. This suggests that the follicular pool in the thirties is large enough and sufficient to sustain fertility.

Ovarian tissue cryopreservation and transplantation: scientific implications

After fresh or frozen ovary transplantation, FSH levels return to normal, and menstrual cycles resume by 150 days, coincident with anti-Müllerian hormone rising to higher than normal levels. AMH then returns to well below normal levels by 240 days, remaining as such for many years with nonetheless normal ovulation and fertility. To date, 20 babies have been born in our program from 11 fresh and 13 cryopreserved ovary transplant recipients with a live baby rate of over 70 % (11 babies from fresh and 9 from frozen). Globally, over 70 live births have been reported for both fresh and frozen ovary transplants with an approximate 30 % live birth rate. Given the rapid rise of AMH after the fall of FSH, with a subsequent AMH decrease with retention of ovarian function, it is tempting to speculate the existence of a shared mechanism controlling primordial follicle recruitment, fetal oocyte meiotic arrest, and recruitment in the adult ovary. With the massive recruitment of primordial follicles observed after human ovarian cortical tissue transplantation, which subsides to an extremely low recruitment rate, we will discuss how this phenomenon suggests a unifying theory implicating ovarian cortical tissue rigidity in the regulation of both fetal oocyte arrest and recruitment of follicles in the adult ovary. As the paper by Winkler-Crepaz et al. in this issue demonstrates, our in vivo results are consistent with the in vitro demonstration that primordial follicles in the fetal cortex are "locked" in development, resulting in meiotic arrest, which spares the oocytes from being rapidly lost all at once (Winkler-Crepaz et al., J Assist Reprod Genet, 1). Winkler-Crepaz et al. demonstrate that follicle loss after ovarian cortex transplantation is unlikely due to ischemic apoptosis, but rather from a "burst" of primordial follicle recruitment. In vivo, primordial follicles are normally resistant to further development or activation to prevent oocyte depletion. The dense fibrous ovarian cortex, through as yet unresolved mechanisms, arrests the further continuation of meiosis and also prevents a sudden depletion of all resting follicles in the adult ovary. Intrinsic tissue pressure is released after cortical tissue transplantation, temporarily resulting in a rapid follicle depletion. These results are consistent with the observation that once the ovarian reserve is reduced in the graft, the rate of recruitment diminishes and the ovarian tissue exhibits a relatively long duration of function.

Fertility preservation through gonadal cryopreservation

Fertility preservation is an area of immense interest in today's society. The most effective and established means of fertility preservation is cryopreservation of gametes (sperm and oocytes) and embryos. Gonadal cryopreservation is yet another means for fertility preservation, especially if the gonadal function is threatened by premature menopause, gonadotoxic cancer treatment, surgical castration, or diseases. It can also aid in the preservation of germplasm of animals that die before attaining sexual maturity. This is especially of significance for valuable, rare, and endangered animals whose population is affected by high neonatal/juvenile mortality because of diseases, poor management practices, or inbreeding depression. Establishing genome resource banks to conserve the genetic status of wild animals will provide a critical interface between ex-situ and in-situ conservation strategies. Cryopreservation of gonads effectively lengthens the genetic lifespan of individuals in a breeding program even after their death and contributes towards germplasm conservation of prized animals. Although the studies on domestic animals are quite promising, there are limitations for developing cryopreservation strategies in wild animals. In this review, we discuss different options for gonadal tissue cryopreservation with respect to humans and to laboratory, domestic, and wild animals. This review also covers recent developments in gonadal tissue cryopreservation and transplantation, providing a systematic view and the advances in the field with the possibility for its application in fertility preservation and for the conservation of germplasm in domestic and wild species.

Surgical Aspects of Ovarian Tissue Removal and Ovarian Tissue Transplantation for Fertility Preservation

Introduction: The removal of ovarian tissue prior to starting oncologic treatment and the subsequent transplantation of this tissue after completing therapy have become increasingly important surgical fertility-preserving techniques. The aim of this review was to investigate the different surgical techniques used for this method reported in the literature to date and to discuss the advantages and disadvantages of the respective techniques. Review: A search was done in MEDLINE using a defined algorithm to find studies published between January 2004 and December 2015. All study designs were included in our review if they contained statements on the surgical technique used. We found 16 publications (8 retrospective cohort studies, 6 case reports and 2 systematic reviews) with a total of 1898 female patients which reported on the surgical technique used for ovarian biopsy and 15 publications (7 retrospective cohort studies, 6 case reports and 2 systematic reviews) with a total of 455 women which mentioned the surgical technique used for ovarian transplantation. Different surgical techniques can be used both for ovarian biopsy and for the transplantation of ovarian tissue. A number of different surgical routes have been used, and the amount of tissue extracted, the instruments used, the treatment of the ovary, the transplantation site, the blood supply to the transplanted ovarian tissue and the procedure used for simultaneous surgical interventions vary. Conclusion: In future, one of the tasks will be to establish a standard surgical method for ovarian extraction and transplantation which will have a low rate of complications and a high pregnancy and birth rate while ensuring that the transplanted tissue is fully functional.

New advances in ovarian autotransplantation to restore fertility in cancer patients

Human ovary autotransplantation is a promising option for fertility preservation of young women and girls undergoing gonadotoxic treatments for cancer or some autoimmune diseases. Although experimental, it resulted in at least 42 healthy babies worldwide. According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic literature review was performed for all relevant full-text articles published in English from 1 January 2000 to 01 October 2015 in PubMed to explore the latest clinical and research advances of human ovary autotransplantation. Human ovary autotransplantation involves ovarian tissue extraction, freezing/thawing, and transplantation back into the same patient. Three major forms of human ovary autotransplantation exist including (a) transplantation of cortical ovarian tissue, (b) transplantation of whole ovary, and (c) transplantation of ovarian follicles (artificial ovary). According to the recent guidelines, human ovary autotransplantation is still considered experimental; however, it has unique advantages in comparison to other options of female fertility preservation. Human ovary autotransplantation (i) does not need prior ovarian stimulation, (ii) allows immediate initiation of cancer therapy, (iii) can restore both endocrine and reproductive ovarian functions, and (iv) may be the only fertility preservation option suitable for prepubertal girls or for young women with estrogen-sensitive malignancies. As any other fertility preservation option, human ovary autotransplantation has both advantages and disadvantages and may not be feasible for all cases. The major challenges facing this option are how to avoid the risk of reintroducing malignant cells and how to prolong the lifespan of ovarian transplant as well as how to improve artificial ovary results.

Female fertility preservation strategies: cryopreservation and ovarian tissue in vitro culture, current state of the art and future perspectives

In the present review, the main strategies of female fertility preservation are covered. Procedures of fertility preservation are necessary for women who suffer from diseases whose treatment requires the use of aggressive therapies, such as chemotherapy and radiotherapy. These kinds of therapy negatively influence the health of gametes and their progenitors. The most commonly used method of female fertility preservation is ovarian tissue cryopreservation, followed by the retransplantation of thawed tissue. Another approach to female fertility preservation that has been actively developed lately is the ovarian tissue in vitro culture. The principal methods, advantages and drawbacks of these two strategies are discussed in this article.

Systematic review of available guidelines on fertility preservation of young patients with breast cancer

BACKGROUND

Since the survival rate of breast cancer patients has improved, harmful effects of new treatment modalities on fertility of the young breast cancer patients has become a focus of attention. This study aimed to systematically review and critically appraise all available guidelines for fertility preservation in young breast cancer patients.

MATERIALS AND METHODS

Major citation databases were searched for treatment guidelines. Experts from relevant disciplines appraised the available guidelines. The AGREE II Instrument that includes 23 criteria in seven domains (scope and purpose of the guidelines, stakeholder involvement, rigor of development, clarity, applicability, editorial independence, and overall quality) was used to apprise and score the guidelines.

RESULTS

The search strategy retrieved 2,606 citations; 72 were considered for full-text screening and seven guidelines were included in the study. There was variability in the scores assigned to different domains among the guidelines. ASCO (2013), with an overall score of 68.0%, had the highest score, and St Gallen, with an overall score of 24.7%, had the lowest scores among the guidelines.

CONCLUSIONS

With the promising survival rate among breast cancer patients, more attention should be given to include specific fertility preservation recommendations for young breast cancer patients.

Transplantation of ovarian tissue

Since the first live birth after orthotopic transplantation of frozen-thawed ovarian tissue, >40 babies have been born. It is time to consider fertility preservation in women as one of the foremost challenges of the next decade and to offer women facing the risk of induced or iatrogenic premature menopause the best chances of becoming mothers. Heterotopic transplantation has also been attempted, with consistent restoration of endocrine function; nonetheless, its clinical value remains questionable as it may not provide an optimal environment for follicular development, possibly because of differences in temperature, pressure, paracrine factors and blood supply. Finally, orthotopic allo-transplantation of fresh human ovarian tissue has been successfully attempted between monozygotic twins and also between genetically different sisters. The next step in this field will be the development of an artificial ovary, using, as a support, a biodegradable scaffold made of an alginate matrigel matrix onto which isolated preantral follicles and ovarian cells can be grafted.

Identification of a β-galactosidase transgene that provides a live-cell marker of transcriptional activity in growing oocytes and embryos

Identifying the events and molecular mechanisms that regulate oocyte growth has emerged as a key objective of research in human fertility, fuelled by evidence from human and animal studies indicating that disease and environmental factors can act on oocytes to affect the health of the resulting individual and by efforts to grow oocytes in vitro to enable fertility preservation of cancer survivors. Techniques that monitor the development of growing oocytes would be valuable tools to assess the progression of growth under different conditions. Most methods used to assess oocytes grown in vitro are indirect, however, relying on characteristics of the somatic compartment of the follicle, or compromise the oocyte, preventing its subsequent culture or fertilization. We investigated the utility of T-cell factor/lymphoid enhancer-binding factor (TCF/Lef)-LacZ transgene expression as a predictor of global transcriptional activity in oocytes and early embryos. Using a fluorescent β-galactosidase substrate combined with live-cell imaging, we show that TCF/Lef-LacZ transgene expression is detectable in growing oocytes, lost in fully grown oocytes and resumes in late two-cell embryos. Transgene expression is likely regulated by a Wnt-independent mechanism. Using chromatin analysis, LacZ expression and methods to monitor and inhibit transcription, we show that TCF/Lef-LacZ expression mirrors transcriptional activity in oocytes and preimplantation embryos. Oocytes and preimplantation embryos that undergo live-cell imaging for TCF/Lef-LacZ expression are able to continue development in vitro. TCF/Lef-LacZ reporter expression in living oocytes and early embryos is thus a sensitive and faithful marker of transcriptional activity that can be used to monitor and optimize conditions for oocyte growth.

Ovarian tissue cryopreservation in girls undergoing haematopoietic stem cell transplant: experience of a single centre

Fertility after childhood haemopoietic stem cell transplant (HSCT) is a major concern. Conditioning regimens before HSCT present a high risk (>80%) of ovarian failure. Since 2000, we have proposed cryopreservation of ovarian tissue to female patients undergoing HSCT at our centre, to preserve future fertility. After clinical and haematological evaluation, the patients underwent ovarian tissue collection by laparoscopy. The tissue was analysed by histologic examination to detect any tumour contamination and then frozen following the slow freezing procedure and cryopreserved in liquid nitrogen. From August 2000 to September 2013, 47 patients planned to receive HSCT, underwent ovarian tissue cryopreservation. The median age at diagnosis was 11.1 years and at the time of procedure it was 13 years, respectively. Twenty-four patients were not pubertal at the time of storage, whereas 23 patients had already experienced menarche. The median time between laparoscopy and HSCT was 25 days. Twenty-six out of 28 evaluable patients (93%) developed hypergonadotropic hypogonadism at a median time of 23.3 months after HSCT. One patient required autologous orthotopic transplantation that resulted in one live birth. Results show a very high rate of iatrogenic hypergonadotropic hypogonadism, highlighting the need for fertility preservation in these patients.

Regenerative medicine for the treatment of reproductive system disorders: current and potential options

Regenerative medicine has opened new avenues for treating patients with severe reproductive system disorders, such as congenital abnormalities, cancer, trauma, infection, inflammation and iatrogenic injuries. Over the past two decades, scientists have advanced the field of reproductive tissue engineering to restore normal sexual function and preserve fertility in both female and male patients. In this review, we summarize recent advances in the use of cell, tissue, and organ-based regenerative medicine strategies for clinical application in reproductive system disorders.

Fertility preservation for age-related fertility decline

Cryopreservation of eggs or ovarian tissue to preserve fertility for patients with cancer has been studied since 1994 with R G Gosden's paper describing restoration of fertility in oophorectomised sheep, and for decades previously by others in smaller mammals. Clinically this approach has shown great success. Many healthy children have been born from eggs cryopreserved with the Kuwayama egg vitrification technique for non-medical (social) indications, but until now very few patients with cancer have achieved pregnancy with cryopreserved eggs. Often, oncologists do not wish to delay cancer treatment while the patient goes through multiple ovarian stimulation cycles to retrieve eggs, and the patient can only start using the oocytes after full recovery from cancer. Ovarian stimulation and egg retrieval is not a barrier for patients without cancer who wish to delay childbearing, which makes oocyte cryopreservation increasingly popular to overcome an age-related decline in fertility. Cryopreservation of ovarian tissue is an option if egg cryopreservation is ruled out. More than 35 babies have been born so far with cryopreserved ovarian tissue in patients with cancer who have had a complete return of hormonal function, and fertility to baseline. Both egg and ovarian tissue cryopreservation might be ready for application to the preservation of fertility not only in patients with cancer but also in countering the increasing incidence of age-related decline in female fertility.

Treatment history and outcome of 24 deliveries worldwide after autotransplantation of cryopreserved ovarian tissue, including two new Danish deliveries years after autotransplantation

PURPOSE

To report another two successful pregnancies and deliveries resulting from autotransplanted cryopreserved ovarian tissue several years after the autotransplantation procedure took place. Further, to review the literature on the treatment history, number of live births and their outcome so far reported worldwide.

METHODS

Two women underwent fertility preservation with cryopreservation of their ovarian tissue prior to a potentially sterilizing treatment with bone marrow transplantation. One woman suffered from paroxystic nocturnal hemoglobinuria and one woman from relapse of Hodgkin's lymphoma. Both suffered from premature ovarian insufficiency after treatment. Because of a pregnancy wish they later had pieces of thawed cortical tissue transplanted to the remaining ovary and the anterior abdominal wall. PubMed was searched for reports of deliveries resulting from cryopreserved ovarian tissue in peer-reviewed papers.

RESULTS

Five years after the autotransplantation the first patient became spontaneously pregnant and delivered a healthy baby boy at term. The second patient became pregnant after undergoing one cycle of in vitro fertilisation five years after the autotransplantation. She delivered a healthy baby boy at gestational week 36. Twenty healthy singletons and two sets of twins have been born according to peer-reviewed publications.

CONCLUSION

Contrary to most of the published deliveries our latest two cases occurred several years after the autotransplantation procedure took place. This proves that ovarian grafts are capable of functioning for several years after the autotransplantation has occurred. Today, a total of 26 healthy children have been born as a result of cryopreservation of ovarian tissue.

Slow-freezing versus vitrification for human ovarian tissue cryopreservation

PURPOSE

Ovarian tissue can be cryopreserved prior to chemotherapy using either the slow-freezing or the vitrification method; however, the data on the equality of the procedures are still conflicting. In this study, a comparison of the cryo-damage of human ovarian tissue induced by either vitrification or slow-freezing was performed.

METHODS

Ovarian tissue from 23 pre-menopausal patients was cryopreserved with either slow-freezing or vitrification. After thawing/warming, the tissue was histologically and immunohistochemically analyzed and cultured in vitro. During tissue culture the estradiol release was assessed.

RESULTS

No significant difference was found in the proportion of high-quality follicles after thawing/warming in the slow-freezing and vitrification group, respectively (72.7 versus 66.7 %, p = 0.733). Estradiol secretion by the ovarian tissue was similar between groups during 18 days in vitro culture (area-under-the-curve 5,411 versus 13,102, p = 0.11). Addition of Sphingosine-1-Phosphate or Activin A to the culture medium did not alter estradiol release in both groups. The proportion of Activated Caspase-3 or 'Proliferating-Cell-Nuclear-Antigen' positive follicles at the end of the culture period was similar between slow-freezing and vitrification.

CONCLUSION(S)

Slow-freezing and vitrification result in similar morphological integrity after cryopreservation, a similar estradiol release in culture, and similar rates of follicular proliferation and apoptosis after culture.