Re-implantation of cryopreserved ovarian cortex resulting in restoration of ovarian function, natural conception and successful pregnancy after haematopoietic stem cell transplantation for Wilms tumour

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.

Clinical pregnancy in Turner syndrome following re-implantation of cryopreserved ovarian cortex

Turner syndrome (TS) leads to a characteristic phenotype, including premature ovarian insufficiency and infertility. Ovarian tissue cryopreservation (OTC) is becoming an established fertility preservation strategy for both pre- and post-pubertal females and may offer the chance of having a biological family to selected patients with TS. To date, women with TS have had ovarian tissue cryopreserved but there are few reports of autologous re-implantation and none of pregnancy. We herein report, to our knowledge, the first clinical pregnancy in a patient with TS, conceived naturally following re-implantation of cryopreserved ovarian tissue which had been removed soon after spontaneous puberty. This provides proof of concept for OTC as a means of fertility preservation in TS.

Human ovarian gross morphology and subanatomy across puberty: insights from tissue donated during fertility preservation

Objective

To study ovarian gross morphologic and subanatomic features across pubertal development.

Design

Prospective cohort study.

Setting

An academic medical center with specimens collected from 2018-2022.

Patients

Tissue was obtained from prepubertal and postpubertal participants (0.19-22.96 years) undergoing ovarian tissue cryopreservation before treatment that put them at a significantly or high increased risk of developing premature ovarian insufficiency. Most participants (64%) had not received chemotherapy at tissue collection.

Interventions

None.

Main Outcome Measures

Ovaries procured for fertility preservation were weighed and measured. Ovarian tissue fragments released during processing, biopsies used for pathology, and hormone panels were analyzed for gross morphology, subanatomic features, and reproductive hormones. Graphical analysis of best-fit lines determined age at maximum growth velocity.

Results

Prepubertal ovaries were significantly (1.4-fold and 2.4-fold) smaller than postpubertal ovaries by length and width and 5.7-fold lighter on average. Length, width, and weight grew in a sigmoidal pattern with age. Prepubertal ovaries were less likely to display a defined corticomedullary junction (53% vs. 77% in postpubertal specimens), less likely to have a tunica albuginea (22% vs. 93% in postpubertal specimens), contained significantly more (9.8-fold) primordial follicles, and contained primordial follicles at significantly deeper depths (2.9-fold) when compared with postpubertal ovaries.

Conclusions

Ovarian tissue cryopreservation is a resource to study human ovarian biology and pubertal development. Maximum growth velocity occurs late within the pubertal transition (Tanner 3+) after changes in subanatomic features. This ovarian morphology model adds to foundational knowledge of human ovarian development and supports ongoing transcriptomics research.

RNA Transcripts in Human Ovarian Cells: Two-Time Cryopreservation Does Not Affect Developmental Potential

Sometimes, for medical reasons, when a frozen tissue has already thawed, an operation by re-transplantation may be cancelled, and ovarian tissues should be re-frozen for transplantation next time. Research about the repeated cryopreservation of ovarian cells is rarely reported. It has been published that there is no difference in the follicle densities, proportions of proliferation of early preantral follicles, appearance of atretic follicles, or ultrastructural quality of frozen-thawed and re-frozen-rethawed tissue. However, the molecular mechanisms of a repeated cryopreservation effect on the developmental potential of ovarian cells are unknown. The aim of our experiments was to investigate the effect of re-freezing and re-thawing ovarian tissue on gene expression, gene function annotation, and protein-protein interactions. The morphological and biological activity of primordial, primary, and secondary follicles, aimed at using these follicles for the formation of artificial ovaries, was also detected. Second-generation mRNA sequencing technology with a high throughput and accuracy was adopted to determine the different transcriptome profiles in the cells of four groups: one-time cryopreserved (frozen and thawed) cells (Group 1), two-time cryopreserved (re-frozen and re-thawed after first cryopreservation) cells (Group 2), one-time cryopreserved (frozen and thawed) and in vitro cultured cells (Group 3), and two times cryopreserved (re-frozen and re-thawed after first cryopreservation) and in vitro cultured cells (Group 4). Some minor changes in the primordial, primary, and secondary follicles in terms of the morphology and biological activity were detected, and finally, the availability of these follicles for the formation of artificial ovaries was explored. It was established that during cryopreservation, the CEBPB/CYP19A1 pathway may be involved in regulating estrogen activity and CD44 is crucial for the development of ovarian cells. An analysis of gene expression in cryopreserved ovarian cells indicates that two-time (repeated) cryopreservation does not significantly affect the developmental potential of these cells. For medical reasons, when ovarian tissue is thawed but cannot be transplanted, it can be immediately re-frozen again.

Development of a digital anti-Müllerian hormone immunoassay: ultrasensitive, accurate and practical strategy for reduced ovarian reserve monitoring and assessment

Anti-Müllerian hormone (AMH) is an ideal biomarker for the assessment of ovarian reserve. However, its application in determining ovarian reserve reduction is restricted due to the low sensitivity of existing AMH assays. Herein, a homebrew ultrasensitive digital AMH assay (UD-AMH) was established based on a single-molecule array (SiMoA, HD-X platform), and the analytical performance of UD-AMH was evaluated systematically. The limit of detection (LoD) and limit of quantitation (LoQ) of UD-AMH were 0.13 and 0.14 pg/mL, respectively, which is approximately 100-fold higher than that of the current reported general clinical AMH assay. A comparison study showed a high correlation, with r = 0.988 for the Beckman Access AMH assay and r = 0.945 for the Kangrun AMH assay. In addition, we found that the AMH concentrations of premature ovarian insufficiency (POI) patients were very low (2.59 (0.86, 31.79) pg/mL) and similar to those of perimenopausal women (2.37 (0.65, 35.88) pg/mL) but significantly higher than those of menopausal women (0.43 (0.28, 1.17) pg/mL). Furthermore, we observed that the AMH concentration of most hormone therapy (HT) treated POI patients decreased sharply, suggesting that the ovarian reserve of POI patients declines over time even under HT-treatment.

Fertility Preservation: How to Preserve Ovarian Function in Children, Adolescents and Adults

Chemotherapy, pelvic radiotherapy and ovarian surgery have known gonadotoxic effects that can lead to endocrine dysfunction, cessation of ovarian endocrine activity and early depletion of the ovarian reserve, causing a risk for future fertility problems, even in children. Important determinants of this risk are the patient’s age and ovarian reserve, type of treatment and dose. When the risk of premature ovarian insufficiency is high, fertility preservation strategies must be offered to the patient. Furthermore, fertility preservation may sometimes be needed in conditions other than cancer, such as in non-malignant diseases or in patients seeking fertility preservation for personal reasons. Oocyte and/or embryo vitrification and ovarian tissue cryopreservation are the two methods currently endorsed by the American Society for Reproductive Medicine, yielding encouraging results in terms of pregnancy and live birth rates. The choice of one technique above the other depends mostly on the age and pubertal status of the patient, and personal and medical circumstances. This review focuses on the available fertility preservation techniques, their appropriateness according to patient age and their efficacy in terms of pregnancy and live birth rates.

Establishment of a Pediatric Ovarian and Testicular Cryopreservation Program for Malignant and Non-Malignant Conditions: The Mayo Clinic Experience

STUDY OBJECTIVES

To describe the structure of a pediatric fertility preservation (FP) program and to share safety and patient satisfaction data.

DESIGN

The FP program operates under prospective research protocols approved by the Mayo Clinic Institutional Review Board (IRB).

SETTING

The FP program is a multidisciplinary effort between pediatric gynecology, reproductive endocrinology, pediatric urology, pediatric surgery, and laboratory medicine.

PARTICIPANTS

The FP program enrolls patients between 0-17 years of age who have been diagnosed with a fertility-threatening condition and/or are scheduled to undergo gonadotoxic treatment.

INTERVENTIONS

FP is offered in the form of ovarian tissue cryopreservation (OTC) and testicular (TTC) tissue cryopreservation.

MAIN OUTCOME MEASURES

The outcome measures are the safety of the procedure and results of patient surveys conducted by phone using a standard list of questions to assess attitudes towards FP.

RESULTS

To date, we have enrolled 38 OTC and 37 TTC patients. The median age (range) of OTC and TTC patients was 11 years (0.83-17 years) and 10 years (0.92-17 years) at the time of enrollment, respectively. Childhood cancers currently represent 88% of the fertility-threatening diagnoses. Meanwhile, patients with non-malignant conditions include those with gender dysphoria, aplastic anemia, and Turner's syndrome. To date, no serious adverse events (SAEs) have been reported following surgery. According to n = 34 one-year follow-ups, 100% of parents felt that FP was a good decision.

CONCLUSION

Consistent with the literature, our data suggests FP is safe and improves the quality of care provided to pediatric patients for their fertility-threatening diagnoses and/or treatments.

TRIAL REGISTRATION

NCT02872532, NCT02646384.

Current Fertility Preservation Options for Female Patients With Hodgkin Lymphoma

Importance

Many adolescents and young adults diagnosed with Hodgkin lymphoma (HL) experience disease progression requiring high-dose alkylating salvage therapy, which often results in permanent infertility.

Objective

The aim of this report is to discuss fertility preservation options in female patients with consideration of chemotherapeutic agents in HL.

Evidence Acquisition

An electronic literature review was performed utilizing a combination of the terms "Hodgkin lymphoma," "fertility preservation," "ovarian tissue cryopreservation," "oocyte cryopreservation," "embryo cryopreservation," and "gonadotropin-releasing hormone agonist." References and data from identified sources were searched and compiled to complete this review.

Results

Initial treatment of HL is often nonsterilizing; however, salvage therapy and conditioning for stem cell transplantation confer significant gonadotoxicity. Established fertility preservation options for pubertal females include embryo cryopreservation and oocyte cryopreservation. These options are contraindicated within 6 months of receipt of chemotherapy. Ovarian tissue cryopreservation is an option for patients who require salvage therapy within 6 months of first-line therapy.

Conclusions

Timing and choice of fertility preservation techniques depends on planned first-line chemotherapy and response to treatment. In patients initially treated with low-risk chemotherapy, it is reasonable to defer invasive fertility techniques until treatment failure; however, upfront fertility preservation should be considered in patients planning to undergo primary treatment with high-risk therapy.

Advances in the Treatment and Prevention of Chemotherapy-Induced Ovarian Toxicity

Due to improvements in chemotherapeutic agents, cancer treatment efficacy and cancer patient survival rates have greatly improved, but unfortunately gonadal damage remains a major complication. Gonadotoxic chemotherapy, including alkylating agents during reproductive age, can lead to iatrogenic premature ovarian insufficiency (POI), and loss of fertility. In recent years, the demand for fertility preservation has increased dramatically among female cancer patients. Currently, embryo and oocyte cryopreservation are the only established options for fertility preservation in women. However, there is growing evidence for other experimental techniques including ovarian tissue cryopreservation, oocyte in vitro maturation, artificial ovaries, stem cell technologies, and ovarian suppression. To prevent fertility loss in women with cancer, individualized fertility preservation options including established and experimental techniques that take into consideration the patient's age, marital status, chemotherapy regimen, and the possibility of treatment delay should be provided. In addition, effective multidisciplinary oncofertility strategies that involve a highly skilled and experienced oncofertility team consisting of medical oncologists, gynecologists, reproductive biologists, surgical oncologists, patient care coordinators, and research scientists are necessary to provide cancer patients with high-quality care.

Fertility preservation in women for medical and social reasons: Oocytes vs ovarian tissue

Approximately 10% of cancers occur in women under 45 years of age. Chemotherapy, radiotherapy, and bone marrow transplantation cure more than 90% of cancer in women, but can result in premature ovarian insufficiency depending on follicular reserve, age, and drugs used. Some benign diseases are also indications for fertility preservation, particularly those requiring chemotherapy (like thalassemia and lupus), recurrent endometriosis, and family history of premature menopause. Social reasons also account for a large proportion of women who wish to postpone pregnancy. This article discusses the two main strategies for fertility preservation, namely oocyte vitrification and ovarian tissue cryopreservation, examining the indications and results of these options. Oocyte cryopreservation is an effective approach, but further studies are needed in cancer patients to ensure the excellent outcomes obtained in women without cancer or in egg donation programs. For prepubertal girls or cases where immediate therapy is required, cryopreservation of ovarian tissue is the only available option.

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.

Fertility Preservation for Pediatric and Adolescent Patients With Cancer: Medical and Ethical Considerations

Many cancers presenting in children and adolescents are curable with surgery, chemotherapy, and/or radiotherapy. Potential adverse consequences of treatment include sterility, infertility, or subfertility as a result of gonad removal, damage to germ cells as a result of adjuvant therapy, or damage to the pituitary and hypothalamus or uterus as a result of irradiation. In recent years, treatment of solid tumors and hematologic malignancies has been modified in an attempt to reduce damage to the gonadal axis. Simultaneously, advances in assisted reproductive technology have led to new possibilities for the prevention and treatment of infertility. This clinical report reviews the medical aspects and ethical considerations that arise when considering fertility preservation in pediatric and adolescent patients with cancer.

Primary gonadal failure

The term primary gonadal failure encompasses not only testicular insufficiency in 46,XY males and ovarian insufficiency in 46,XX females, but also those disorders of sex development (DSD) which result in gender assignment that is at variance with the genotype and gonadal type. In boys, causes of gonadal failure include Klinefelter and other aneuploidy syndromes, bilateral cryptorchidism, testicular torsion, and forms of 46,XY DSD such as partial androgen insensitivity. Causes in girls include Turner syndrome and other aneuploidies, galactosemia, and autoimmune ovarian failure. Iatrogenic causes in both boys and girls include the late effects of childhood cancer treatment, total body irradiation prior to bone marrow transplantation, and iron overload in transfusion-dependent thalassaemia. In this paper, a brief description of the physiology of testicular and ovarian development is followed by a section on the causes and practical management of gonadal impairment in boys and girls. Protocols for pubertal induction and post-pubertal hormone replacement - intramuscular, oral and transdermal testosterone in boys; oral and transdermal oestrogen in girls - are then given. Finally, current and future strategies for assisted conception and fertility preservation are discussed.

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.

A case report and follow-up of the first live birth after heterotopic transplantation of cryopreserved ovarian tissue in Eastern Europe

Background

Ovarian insufficiency is a major concern for long-term cancer survivors. Although semen freezing is well established to preserve male fertility, the possibilities to secure post-cancer female fertility are mostly limited to oocyte or embryo freezing. These methods require time-consuming ovarian stimulation with or without in vitro fertilization (IVF) that evidently delays cancer therapy. Ovarian tissue cryopreservation and subsequent thawed tissue autotransplantation are considered the most promising alternative strategy for restoring the fertility of oncology patients, which has not yet received the full clinical acceptance. Therefore, all successful cases are needed to prove its reliability and safety.

Case presentation

Here we report a single case in Estonia, where a 28-year-old woman with malignant breast neoplasm had ovarian cortex cryopreserved before commencing gonadotoxic chemo- and radiotherapy. Two years after cancer therapy, the patient underwent heterotopic ovarian tissue transplantation into the lateral pelvic wall. The folliculogenesis was stimulated in the transplanted tissue by exogenous follicle-stimulating hormone and oocytes were collected under ultrasound guidance for IVF and embryo transfer. The healthy boy was born after full-term gestation in 2014, first in Eastern Europe.

Conclusion

Despite many countries have reported the first implementation of the ovarian tissue freezing and transplantation protocols, the data is still limited on the effectiveness of heterotopic ovarian transplant techniques. Thus, all case reports of heterotopic ovarian tissue transplantation and long-term follow-ups to describe the children’s health are valuable source of clinical experience.

Slush nitrogen vitrification of human ovarian tissue does not alter gene expression and improves follicle health and progression in long-term in vitro culture

OBJECTIVE

To study whether slush nitrogen (SN) vs. liquid nitrogen (LN) vitrification affects human ovarian tissue gene expression and preserves follicle health during extended in vitro culture.

DESIGN

Randomized experimental study.

SETTING

University research laboratory.

PATIENT(S)

Ovarian biopsies collected by laparoscopic surgery from patients with benign gynaecologic conditions.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Ovarian strips were vitrified with LN or SN, warmed, and analyzed before or after culture for 9 days (d9) in gas-permeable dishes. Expression of genes involved in stress and toxicity pathways was analyzed in fresh and warmed strips by polymerase chain reaction (PCR) array and quantitative real-time-PCR. Fresh and vitrified/warmed strips were analyzed for follicle quality, progression, and viability before or after culture.

RESULT(S)

The SN vitrification preserved follicle quality better than LN (% grade 1 follicles: fresh control, 54.2; LN, 29.3; SN, 48.8). Quantitative reverse transcription-PCR demonstrated a noticeable up-regulation of 13 genes in LN samples (range, 10-35) and a markedly lower up-regulation of only 5 genes (range, 3.6-7.8) in SN samples. Long-term in vitro culture evidenced worse follicle quality and viability in LN samples than in both fresh and SN samples (% grade 1 follicle: fresh d0, 51.5; fresh d9, 41; LN d9, 16.4; SN d9, 55) and a highly significant reduction of primordial follicles and a concomitant increase of primary and secondary follicles in all samples. Follicle growth to the secondary stage was significantly higher in vitrified tissue than in fresh tissue, being better in SN than in LN vitrified tissue.

CONCLUSION(S)

Follicle quality, gene expression, viability, and progression are better preserved after SN vitrification.

Cryostorage and retransplantation of ovarian tissue as an infertility treatment

While still considered an experimental procedure in most countries, ovarian tissue cryopreservation and transplantation has been increasingly applied worldwide to restore fertility in patients with malignant and non-malignant pathologies with risk of premature ovarian insufficiency. It has yielded more than 130 live births up to now and almost all transplanted patients recovered their ovarian function. This study summarizes ovarian tissue cryopreservation and transplantation indications, procedures, their efficacy and main results and proposes different strategies to improve this strategy. Although the main focus of this study is on ovarian tissue cryopreservation and transplantation as a strategy to restore fertility, we believe that it is also important to discuss other applications for this approach.

First Italian birth after cryopreserved ovarian tissue transplantation in a patient affected by non-Hodgkin's lymphoma

This case report describes the first Italian live birth obtained by cryopreserved ovarian tissue transplantation in a woman affected by non-Hodgkin's lymphoma. Before anticancer treatments, several fertility preservation options were proposed. At 29 years the patient underwent laparoscopy for ovarian tissue cryopreservation. After treatments she experienced premature ovarian failure (POF) and asked for cryopreserved ovarian tissue transplantation. Before transplantation, ovarian samples were analyzed to assess neoplastic contamination and tissue quality. Two subsequent ovarian tissue transplantations were performed 4 and 7 years after cryopreservation. The follicle-stimulating hormone and luteinizing hormone reduction, estradiol increase and first menstrual cycle appeared 2 months after the second transplantation. The woman conceived spontaneously 5 months after the second transplantation. After 39 weeks of uneventful gestation, a healthy male baby was born. Ovarian tissue cryopreservation, thawing and transplantation successfully restored ovarian function and fertility after tissue storage.

Cat ovarian follicle ultrastructure after cryopreservation with ethylene glycol and dimethyl sulfoxide

Ovarian tissue cryopreservation is a promising technique for fertility maintenance. The aim of this study was to compare the morphology of domestic cat ovarian follicles after tissue cryopreservation with ethylene glycol (EG) and dimethyl sulfoxide (Me₂SO). Ovaries from healthy adult cats undergoing elective ovariohysterectomy were used. Eight fragments were obtained from each pair of ovaries: two were used as fresh controls; three were submitted to fresh perfusion toxicity test and perfused with M199, 10% fetal calf serum and 0.4% sucrose containing Me₂SO 1.5 M, EG 1.5 M or Me₂SO 0.75 M + EG 0.75 M; and the remaining three fragments were perfused as described and submitted to slow freezing. After 45 days of cryopreservation, the samples were thawed, fixed and processed for light and transmission electron microscopy (TEM). The percentages of morphologically normal follicles identified by light microscopy were higher in the control group (94.45%) in comparison to the frozen groups (80.56% with EG, 78.7% with Me₂SO and 75.87% with EG + Me₂SO). The fresh perfused tissue showed no statistical difference compared to control or frozen samples. The TEM analysis showed less damage in the ultrastructure of follicles from the Me₂SO group in comparison with the EG and Me₂SO + EG groups. According to the morphological analysis, 1.5 M Me₂SO is the best cryoprotectant for cryopreservation of domestic cat ovarian tissue regarding the morphology of preantral follicles after thawing. Further studies regarding the viability of these follicles should be performed.

Ovarian function, fertility and reproductive lifespan in cancer patients

INTRODUCTION

The increasing survival of girls and young women after cancer has led to a rapid growth in research into assessment of ovarian function after treatment.

AREAS COVERED

This aim of this review is to discuss normal ovarian function over time, the impact of cancer treatment on ovarian function, the assessment of ovarian reserve after treatment, and pretreatment predictors of ovarian recovery.

EXPERT COMMENTARY

Ovarian function damage after chemotherapy and radiotherapy will impact on fertility and reproductive lifespan, but with great variability. Age at menopause has implications for the duration of estrogen deficiency, with its own adverse health consequences. This has led to identification of the key treatment and patient factors at the time of treatment, notably age and ovarian reserve that impact on post-treatment ovarian function. However, most studies have used outcome measures such as ongoing menses, or biomarkers such as anti-mullerian hormone (AMH), with few reporting on fertility or age at menopause.

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.

Untapped Reserves: Controlling Primordial Follicle Growth Activation

Even with the benefit of assisted reproductive technologies (ART), many women are unable to conceive and deliver healthy offspring. One common cause of infertility is the inability to produce eggs capable of contributing to live birth. This can occur despite standard-of-care treatment to maximize the recovery of eggs from growing ovarian follicles. Dormant primordial follicles in the human ovary are a 'reserve ' that can be exploited clinically to overcome this problem. We discuss how controlling primordial follicle growth activation (PFGA) can produce increased numbers of high-quality eggs available for fertility treatment(s). We consider the state of the art in interventions used to control PFGA, and consider genetic and epigenetic strategies on the horizon that might improve compromised oocyte quality to increase live births.

Ovarian tissue cryopreservation (OTC) in prepubertal girls and young women: an analysis of parents' and patients' decision-making

PURPOSE

The purpose of this study was to explore the decision-making influences, perceived level of control over decision-making, and mood states of parents and patients who were offered OTC prior to gonadotoxic therapy.

METHODS

Parents and patients, at least 12 years old, who required gonadotoxic therapy and were offered OTC prior to therapy, were asked to complete questionnaires. Two validated instruments were also used: the Decision-Making Control Instrument (DMCI) and the Profile of Mood States (POMS). The factors that influenced decision-making were compared using Student's t test, and the scores of DMCI and POMS were compared using the Mann-Whitney test.

RESULTS

Thirty-six parents and 16 patients who elected ovarian tissue cryopreservation (OTC) completed questionnaires. Five parents who declined OTC also completed questionnaires. Accepters thought OTC was a good idea and that, in the future, science would enable cryopreserved ovarian tissue to be used to restore fertility (100% parents, 93.8% patients). Among accepters, the desire for genetically related children and prevention of the stress of infertility drove parents' and patients' decisions (90.9 and 100%, respectively). The desire to prevent the stress of infertility was important to parents, but patients were less likely to report that a desire to prevent the stress of infertility factored into their decision-making (66.7 vs. 50.0%; p < 0.001). All respondents felt in control of their decision and displayed low levels of mood disturbance.

CONCLUSIONS

Though the decision to undergo experimental OTC is difficult and often urgent, this study suggests that families feel in control of their decision-making and report little emotional disturbance.

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.

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.

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.