Evaluation of ovarian tissue transplantation: results from three clinical centers

Fertility after Cancer: Risks and Successes

The incidence of cancer in reproductive-aged women is 7%, but, despite the increased number of cancer cases, advances in early diagnosis and treatment have raised the survival rate. Furthermore, in the last four decades, there has been a rising trend of delaying childbearing. There has been an increasing number of couples referred to Reproductive Medicine Centers for infertility problems after one partner has been treated for cancer. In these cases, the main cause of reduced fertility derives from treatments. In this review, we describe the effects and the risks of chemotherapy, radiotherapy, and surgery in women with cancer, and we will focus on available fertility preservation techniques and their efficacy in terms of success in pregnancy and live birth rates.

Fresh and cryopreserved ovarian tissue transplantation for preserving reproductive and endocrine function: a systematic review and individual patient data meta-analysis

BACKGROUND

Ovarian tissue cryopreservation involves freezing and storing of surgically retrieved ovarian tissue in liquid or vapour nitrogen below -190°C. The tissue can be thawed and transplanted back with the aim of restoring fertility or ovarian endocrine function. The techniques for human ovarian tissue freezing and transplantation have evolved over the last 20 years, particularly in the context of fertility preservation in pre-pubertal cancer patients. Fresh ovarian tissue transplantation, using an autograft or donor tissue, is a more recent development; it has the potential to preserve fertility and hormonal function in women who have their ovaries removed for benign gynaecological conditions. The techniques of ovarian tissue cryopreservation and transplantation have progressed rapidly since inception; however, the evidence on the success of this intervention is largely based on case reports and case series.

OBJECTIVE AND RATIONALE

The aim of this study was to systematically review the current evidence by incorporating study-level and individual patient-level meta-analyses of women who received ovarian transplants, including frozen-thawed transplant, fresh or donor graft.

SEARCH METHODS

The review protocol was registered with PROSPERO (CRD42018115233). A comprehensive literature search was performed using MEDLINE, EMBASE, CINAHL and Cochrane Central Register of Controlled Trials from database inception to October 2020. Authors were also contacted for individual patient data if relevant outcomes were not reported in the published manuscripts. Meta-analysis was performed using inverse-variance weighting to calculate summary estimates using a fixed-effects model.

OUTCOMES

The review included 87 studies (735 women). Twenty studies reported on ≥5 cases of ovarian transplants and were included in the meta-analysis (568 women). Fertility outcomes included pregnancy, live birth and miscarriage rates, and endocrine outcomes included oestrogen, FSH and LH levels. The pooled rates were 37% (95% CI: 32-43%) for pregnancy, 28% (95% CI: 24-34%) for live birth and 37% (95% CI: 30-46%) for miscarriage following frozen ovarian tissue transplantation. Pooled mean for pre-transplant oestrogen was 101.6 pmol/l (95% CI: 47.9-155.3), which increased post-transplant to 522.4 pmol/l (95% CI: 315.4-729; mean difference: 228.24; 95% CI: 180.5-276). Pooled mean of pre-transplant FSH was 66.4 IU/l (95% CI: 52.8-84), which decreased post-transplant to 14.1 IU/l (95% CI: 10.9-17.3; mean difference 61.8; 95% CI: 57-66.6). The median time to return of FSH to a value <25 IU/l was 19 weeks (interquartile range: 15-26 weeks; range: 0.4-208 weeks). The median duration of graft function was 2.5 years (interquartile range: 1.4-3.4 years; range: 0.7-5 years). The analysis demonstrated that ovarian tissue cryopreservation and transplantation could restore reproductive and hormonal functions in women. Further studies with larger samples of well-characterized populations are required to define the optimal retrieval, cryopreservation and transplantation processes.

WIDER IMPLICATIONS

Ovarian tissue cryopreservation and transplantation may not only be effective in restoring fertility but also the return of reproductive endocrine function. Although this technology was developed as a fertility preservation option, it may have the scope to be considered for endocrine function preservation.

A comparison of fertility preservation outcomes in patients who froze oocytes, embryos, or ovarian tissue for medically indicated circumstances: a systematic review and meta-analysis

OBJECTIVE

To compare obstetric outcomes in patients cryopreserving reproductive cells or tissues before gonadotoxic therapy.

DESIGN

A literature search was conducted following PRISMA guidelines on Embase, Medline, and Web of Science. Studies reporting obstetric outcomes in cancer patients who completed cryopreservation of oocyte, embryo, or ovarian tissue were included.

SETTING

Not applicable.

PATIENT(S)

Cancer patients attempting pregnancy using cryopreserved cells or tissues frozen before cancer therapy.

INTERVENTION(S)

Oocyte, embryo, or ovarian tissue cryopreservation for fertility preservation in cancer.

MAIN OUTCOME MEASURE(S)

The total numbers of clinical pregnancies, live births, and miscarriages in women attempting pregnancy using cryopreserved reproductive cells or tissues were calculated. A meta-analysis determined the effect size of each intervention.

RESULT(S)

The search returned 4,038 unique entries. Thirty-eight eligible studies were analyzed. The clinical pregnancy rates were 34.9%, 49.0%, and 43.8% for oocyte, embryo, and ovarian tissue cryopreservation, respectively. No significant differences were found among groups. The live birth rates were 25.8%, 35.3%, and 32.3% for oocyte, embryo, and ovarian tissue cryopreservation, respectively, with no significant differences among groups. The miscarriage rates were 9.2%, 16.9%, and 7.5% for oocyte, embryo, and ovarian tissue cryopreservation, respectively. Significantly fewer miscarriages occurred with ovarian tissue cryopreservation than with embryo cryopreservation.

CONCLUSION(S)

This enquiry is required to counsel cancer patients wishing to preserve fertility. Although the limitations of this study include heterogeneity, lack of quality studies, and low utilization rates, it serves as a starting point for comparison of reproductive and obstetric outcomes in patients returning for family-planning after gonadotoxic therapy.

In-vitro maturation and transplantation of cryopreserved ovary tissue: understanding ovarian longevity

RESEARCH QUESTION

Is it possible to use experience gained from 24 years of frozen ovarian transplantation, and from recent experience with in-vitro gametogenesis to accomplish simple and robust in-vitro maturation (IVM) of oocytes from human ovarian tissue?

DESIGN

A total of 119 female patients between age 2 and 35 years old underwent ovary cryopreservation (as well as in-vitro maturation of oocytes and IVM in the last 13 individuals) over a 24-year period. Up to 22 years later, 17 returned to have their ovary tissue thawed and transplanted back.

RESULTS

Every woman had a return of ovarian function 5 months after transplant, similar to previous observations. As observed before, anti-Müllerian hormone (AMH) concentration rose as FSH fell 4 months later. The grafts continued to work up to 8 years. Of the 17, 13 (76%) became pregnant with intercourse at least once, resulting in 19 healthy live births, including six live births from three women who had had leukaemia. Of the harvested germinal vesicle oocytes, 35% developed with simple culture media into mature metaphase II oocytes.

CONCLUSIONS

The authors concluded the following. First, ovary tissue cryopreservation is a robust method for preserving fertility even for women with leukaemia, without a need to delay cancer treatment. Second, many mature oocytes can often be obtained from ovary tissue with simple media and no need for ovarian stimulation. Third, ovarian stimulation only be necessary for removing the oocyte from the ovary, which can also be accomplished by simple dissection at the time of ovary freezing. Finally, pressure and just eight 'core genes' control primordial follicle recruitment and development.

Cost-effectiveness analysis of ovarian tissue cryopreservation and transplantation for preservation of fertility in post-pubertal oncological women submitted to high-risk gonadotoxic chemotherapy

OBJECTIVE

To study the economic impact of ovarian tissue cryopreservation and transplantation (OTC) in post-pubertal patients who underwent high-risk gonadotoxic chemotherapy.

METHODS

A decision tree model was used to determine the live birth rate and cost-effectiveness of OTC versus non-OTC. The incremental cost-effectiveness ratio (ICER) was calculated. A sensitivity analysis was performed under the assumption that the costs of ovarian cortex retrieval, cryopreservation, and storage for patients with cancer might be covered by the national health system or health insurance.

RESULTS

Patients had the greatest probability of achieving live birth after high-risk chemotherapy when they underwent OTC versus non-OTC. Although cryopreservation of ovarian tissue results in higher live birth rates, it is always more expensive. Cost-effectiveness increases when the majority of patients completes the path of tissue cryopreservation plus transplantation after 5 years.

CONCLUSION

Although OCT has been demonstrated as a procedure for effective fertility preservation in fertility-age women with cancer, no cost-effectiveness analysis has been performed until now. This model could help healthcare systems to allocate coverage for OCT.

Minimal residual disease detection by multicolor flow cytometry in cryopreserved ovarian tissue from leukemia patients

Background

Cryopreservation of ovarian tissue is a fertility-preservation option for women before gonadotoxic treatments. However, cryopreserved ovarian tissue transplantation must be performed with caution in women with malignancies that may metastasize to the ovaries. For this purpose, detecting minimal residual disease (MRD) in the ovarian cortex using sensitive methods is a crucial step. We developed an automated ovarian tissue dissociation method to obtain ovarian cell suspensions.

Results

We assessed MRD by multicolor flow cytometry (MFC) in cryopreserved ovarian cortex of 15 leukemia patients: 6 with B-cell acute lymphoblastic leukemia (B-ALL), 2 with T-cell acute lymphoblastic leukemia (T-ALL) and 7 with acute myeloid leukemia (AML). Ovarian MRD was positive in 5 of the 15 leukemia patients (one T-ALL and 4 AML). No B-ALL patient was positive by MFC. Quantitative reverse-transcribed polymerase chain reaction was performed when a molecular marker was available, and confirmed the MFC results for 3 patients tested. Xenografts into immunodeficient mice were also performed with ovarian cortical tissue from 10 leukemia patients, with no evidence of leukemic cells after the 6-month grafting period.

Conclusions

In conclusion, this is the first study using MFC to detect MRD in ovarian cortical tissue from acute leukemia patients. MFC has been accepted in clinical practice for its ease of use, the large number of parameters available simultaneously, and high throughput analysis. We demonstrate here that MFC is a reliable method to detect MRD in cryopreserved ovarian tissue, with a view to controlling the oncological risk before ovarian tissue transplantation in leukemia patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-021-00936-4.

A Systematic Review of Ovarian Tissue Transplantation Outcomes by Ovarian Tissue Processing Size for Cryopreservation

Ovarian tissue cryopreservation (OTC) is the only pre-treatment option currently available to preserve fertility for prepubescent girls and patients who cannot undergo ovarian stimulation. Currently, there is no standardized method of processing ovarian tissue for cryopreservation, despite evidence that fragmentation of ovaries may trigger primordial follicle activation. Because fragmentation may influence ovarian transplant function, the purpose of this systematic review was (1) to identify the processing sizes and dimensions of ovarian tissue within sites around the world, and (2) to examine the reported outcomes of ovarian tissue transplantation including, reported duration of hormone restoration, pregnancy, and live birth. A total of 2,252 abstracts were screened against the inclusion criteria. In this systematic review, 103 studies were included for analysis of tissue processing size and 21 studies were included for analysis of ovarian transplantation outcomes. Only studies where ovarian tissue was cryopreserved (via slow freezing or vitrification) and transplanted orthotopically were included in the review. The size of cryopreserved ovarian tissue was categorized based on dimensions into strips, squares, and fragments. Of the 103 studies, 58 fertility preservation sites were identified that processed ovarian tissue into strips (62%), squares (25.8%), or fragments (31%). Ovarian tissue transplantation was performed in 92 participants that had ovarian tissue cryopreserved into strips (n = 51), squares (n = 37), and fragments (n = 4). All participants had ovarian tissue cryopreserved by slow freezing. The pregnancy rate was 81.3%, 45.5%, 66.7% in the strips, squares, fragment groups, respectively. The live birth rate was 56.3%, 18.2%, 66.7% in the strips, squares, fragment groups, respectively. The mean time from ovarian tissue transplantation to ovarian hormone restoration was 3.88 months, 3.56 months, and 3 months in the strips, squares, and fragments groups, respectively. There was no significant difference between the time of ovarian function' restoration and the size of ovarian tissue. Transplantation of ovarian tissue, regardless of its processing dimensions, restores ovarian hormone activity in the participants that were reported in the literature. More detailed information about the tissue processing size and outcomes post-transplant are required to identify a preferred or more successful processing method.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk], identifier [CRD42020189120].

Differences in gonadal tissue cryopreservation practices for differences of sex development across regions in the United States

OBJECTIVE

Some individuals with differences of sex development (DSD) conditions undergo medically indicated prophylactic gonadectomy. Gonads of individuals with DSD can contain germ cells and precursors and patients interested in future fertility preservation and hormonal restoration can participate in DSD-specific research protocols to cryopreserve this tissue. However, it is unclear how many providers or institutions offer gonadal tissue cryopreservation (GTC) and how widespread GTC for DSD is across the United States (US). The Pediatric Initiative Network (PIN) and Non-Oncologic Conditions committees of the Oncofertility Consortium sought to assess the current state of GTC for patients with DSD.

METHODS

An electronic survey was sent to providers caring for patients with DSD via special interest groups of professional societies and research networks.

RESULTS

The survey was administered between November 15, 2021 and March 14, 2022. A total of 155 providers responded to the survey, of which 132 respondents care for patients with DSD, and 78 work at facilities that offer medically indicated gonadectomy to patients with DSD diagnoses. They represented 55 US institutions including 47 pediatric hospitals, and 5 international sites (Canada, Denmark, Germany, Qatar). Of individual providers, 41% offer cryopreservation after prophylactic gonadectomy for patients with DSD (32/78). At an institutional level, GTC after medically indicated gonadectomy is available at 54.4% (24/46) of institutions. GTC is offered for a variety of DSD diagnoses, most commonly 45,X/46,XY DSD (i.e., Turner Syndrome with Y-chromosome material and mixed gonadal dysgenesis), ovotesticular DSD, complete androgen insensitivity syndrome (CAIS), and complete gonadal dysgenesis. Responses demonstrate regional trends in GTC practices with 83.3% of institutions in the Midwest, 66.7% in the Northeast, 54.6% in the West, and 35.3% in the South providing GTC. All represented institutions (100%) send gonadal tissue for pathological evaluation, and 22.7% preserve tissue for research purposes.

CONCLUSIONS

GTC after gonadectomy is offered at half of the US institutions represented in our survey, though a minority are currently preserving tissue for research purposes. GTC is offered for several DSD conditions. Future research will focus on examining presence and quality of germ cells to support clinical decision making related to fertility preservation for patients with DSD.

Learning curve of surgeons performing laparoscopic ovarian tissue transplantation in women with premature ovarian insufficiency: A statistical process control analysis

STUDY OBJECTIVE

To analyze patient safety in laparoscopic ovarian tissue transplantation surgery by tracking the rate of postoperative complications and the learning curves of the surgeons by statistical process control (SPC) analysis.

DESIGN

A retrospective study.

SETTING

A university-affiliated hospital.

PATIENTS

One hundred patients with premature ovarian insufficiency (POI) who underwent ovarian tissue cryopreservation by vitrification and then autologous transplantation of frozen-thawed ovarian tissues with in vitro activation (IVA).

INTERVENTION

Ovarian tissue cryopreservation, in vitro activation and transplantation.

MEASUREMENTS AND MAIN RESULTS

We assessed the surgery complications, differences in total surgery time, transplantation time, and transplantation time per ovarian sheet in operations performed by 3 experienced laparoscopic surgeons. Surgeon A performed 80 operations; surgeon B, 29 operations; and surgeon C, 20 operations. Complications occurred in 1.55% of the procedures. While all three surgeons' performance never fell below the unacceptable failure limit, only surgeon A became competent after 66 cases.

CONCLUSION

The laparoscopic ovarian tissue transplantation surgery was generally safe as the postoperative complications were infrequent (1.55%). Although the performance of all 3 surgeons was acceptable, only surgeon A attained the level of competency after 66 cases. The transplantation method may not be the key factor for reducing surgery time in this surgery. An efficient OTT team is more important in reducing the surgery time than the surgeon's surgical technique alone.

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.

Longitudinal study of AMH variations in 122 Adolescents and Young Adults (AYA) and non-AYA lymphoma patients to evaluate the chemo-induced ovarian toxicity to further personalise fertility preservation counselling

STUDY QUESTION

What is the influence of age and chemotherapy regimen on the longitudinal blood anti-Müllerian hormone (AMH) variations in a large series of adolescents and young adult (AYA) (15-24 years old) and non-AYA (25-35 years old) lymphoma patients?

SUMMARY ANSWER

In case of alkylating regimen treatment, there was a deep and sustained follicular depletion in AYA as well as non-AYA patients; however in both groups, the ovarian toxicity was extremely low in cases of non-alkylating treatments.

WHAT IS KNOWN ALREADY

AMH is now well-recognised to be a real-time indicator of ovarian follicular depletion and recovery in women treated by chemotherapy. Its longitudinal variations may discriminate between highly and minimally toxic protocols regarding ovarian function. It has been shown, in different cancer types, that age, type of chemotherapy regimen and pre-treatment AMH levels are the main predictors of ovarian recovery. Large studies on longitudinal AMH variations under chemotherapy in lymphoma patients are few but can provide the opportunity to assess the degree of follicle loss at a young age.

STUDY DESIGN, SIZE, DURATION

This prospective cohort study was conducted in the Fertility Observatory of the Lille University Hospital. Data were collected between 2007 and 2016. Non-Hodgkin or Hodgkin lymphoma patients (n = 122) between 15 and 35 years old were prospectively recruited before commencing chemotherapy. Patients were treated either by a non-alkylating protocol (ABVD group; n = 67) or by an alkylating regimen (alkylating group; n = 55).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Serial AMH measurements were performed at baseline (AMH0), 15 days after the start of chemotherapy (AMH1), 15 days before the last chemotherapy cycle (AMH2), and at time 3, 6, 9, 12, 18 and 24 months from the end of chemotherapy. The whole study population was divided into two groups according to age: AYA (15-24; n = 65) and non-AYA (25-35; n = 57). All patients received a once monthly GnRH agonist injection during the whole treatment period. A linear mixed model was used to account for the repeated measures of single patients.

MAIN RESULTS AND THE ROLE OF CHANCE

At baseline, non-AYA patients had higher BMI and lower AMH levels than AYA patients. All AYA and non-AYA patients having received ABVD protocols had regular cycles at 12 months of follow-up. In case of alkylating regimens, amenorrhoea was more frequent in non-AYA patients than in AYA patients at 12 months (37% vs 4%, P = 0.011) and at 24 months (24% vs 4%, P = 0.045). We distinguished a similar depletion phase from AMH0 to AMH2 between ABVD and alkylating groups but significantly different recovery phases from AMH2 to AMH + 24 months. AMH recovery was fast and complete in case of ABVD protocols whatever the age: AMH reached pre-treatment values as soon as the 6th month of follow-up in the AYA group (mean (95% CI) in log AMH M0 vs M6: 3.07 (2.86 to 3.27) vs 3.05 (2.78 to 3.31), P = 1.00) and in the non-AYA group (mean (95% CI) in log AMH M0 vs M6: 2.73 (2.40 to 3.05) vs 2.47 (2.21 to 2.74), P = 1.00). In contrast, no patients from the alkylating group returned to pre-treatment AMH values whatever the age of patients (AYA or non-AYA). Moreover, none of the AMH values post-chemotherapy in the non-AYA group were significantly different from AMH2. Conversely in the AYA group, AMH levels from 6 months (mean (95% CI) in log AMH: 1.79 (1.47 to 2.11), P < 0.001) to 24 months (mean (95% CI) in log AMH: 2.16 (1.80 to 2.52), P ≤ 0.001) were significantly higher than AMH2 (mean (95% CI) in log AMH: 1.13 (0.89 to 1.38)). Considering the whole study population (AYA and non-AYA), pre-treatment AMH levels influenced the pattern of the AMH variation both in alkylating and ABVD protocols (interaction P-value = 0.005 and 0.043, respectively). Likewise, age was significantly associated with the pattern of the recovery phase but only in the alkylating group (interaction P-value =0.001). BMI had no influence on the AMH recovery phase whatever the protocol (interaction P-value = 0.98 in alkylating group, 0.72 in ABVD group).

LIMITATIONS, REASONS FOR CAUTION

There was a large disparity in subtypes of protocols in the alkylating group. The average duration of chemotherapy for patients treated with alkylating protocols was longer than that for patients treated with ABVD.

WIDER IMPLICATIONS OF THE FINDINGS

These results make it possible to develop strategies for fertility preservation according to age and type of protocol in a large series of young lymphoma patients. In addition, it was confirmed that young age does not protect against ovarian damage caused by alkylating agents.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by Agence Régionale de Santé Hauts de France and Agence Onco Hauts-de-France who provided finances for AMH dosages (n° DOS/SDES/AR/FIR/2019/282). There are no competing interests.

TRIAL REGISTRATION NUMBER

DC-2008-642 and CNIL DEC2015-112.

Applying plastic surgery principles to ovarian tissue transplantation

Ovarian tissue cryopreservation (OTC) and transplantation is an innovative procedure increasingly utilized to help preserve fertility after gonadotoxic treatments especially in cancer patients. Approximately 30% of autotransplanted patients are able to achieve live birth, typically with the help of in-vitro fertilization. Numerous techniques and grafting sites have been described to continue to increase this figure. In the field of plastic surgery, tissue grafting has been successful performed for thousands of years and knowledge in this area has been significantly refined. A qualitative review of the literature using PubMed, Cochrane, SCOPUS and Medline databases was performed to look for articles relating to ovarian tissue transplantation (OTT) and comparisons made to plastic surgery tissue grafting. Many parallels were found between the principles of grafting in plastic surgery and the principles of OTT, including pre-operative patient optimization, suitable donor site selection, tissue harvest and preparation, graft site choice, immobilization of the graft and post-operative care. Consideration of the benefits and risks of using orthotopic versus heterotopic recipient sites is also highly important with regards to graft take, morbidity and ease of access of oocyte collection. We believe that ongoing discussion between disciplines can have the potential to improve knowledge, surgical techniques and patient outcomes.

Comparison of open and a novel closed vitrification system with slow freezing for human ovarian tissue cryopreservation

PURPOSE

To investigate the differences concerning post-thawing/warming follicle survival, DNA damage and apoptosis in human ovarian tissues cryopreserved by slow freezing, open, or closed vitrification methods.

METHODS

A total of 50 pieces of 5 × 5 × 1 mm ovarian cortical pieces were harvested (5 donor ovaries; mean age 31 ± 6.62 years). From each donor, one cortical piece was used as baseline; the remaining were randomly assigned to slow freezing (SF), vitrification using open device (VF-open), or closed device (VF-closed) groups. After 8-10 weeks of cryostorage, tissues were evaluated 4 h after thawing/warming. Histological analysis was evaluated for follicle survival (primordial and primary follicle densities) by H&E staining. The percentages of primordial and primary follicles with DNA double-strand breaks (γH2AX) and apoptotic cell death pathway activation (AC3) were immunohistochemically assessed. Data were analysed using one-way ANOVA and LSD post hoc comparison.

RESULTS

Compared to the baseline, primordial follicle (pdf) densities significantly declined in all cryopreserved groups (SF, VF-open, and VF-closed, P < 0.05). However, the total and non-apoptotic pdf densities were similar among SF, VF-open, and VF-closed. SF and VF with either open or closed devices did not increase the percentages of primordial or primary follicles with DNA double-strand breaks (DSBs) or apoptosis compared to the baseline or among the freezing methods in the present study.

CONCLUSION

Based on the intact primordial follicle survival, DNA damage, and apoptosis rates after thawing/warming, SF vs VF with either open or newly developed closed devices appear to be comparable.

Experience with transplantation of human cryopreserved ovarian tissue to a sub-peritoneal abdominal site

STUDY QUESTION

Is a sub-peritoneal abdominal site a suitable site for cryopreserved ovarian tissue transplantation?

SUMMARY ANSWER

Live births have resulted from oocytes aspirated from follicles within cryopreserved ovarian tissue transplanted in a sub-peritoneal abdominal site with similar outcomes observed in terms of number of mature oocytes recovered and embryo development from tissue transplanted to sub-peritoneal abdominal, ovarian, and pelvic sites in our clinic.

WHAT IS KNOWN ALREADY

Over 130 live births have been reported from cryopreservation of ovarian tissue and subsequent transplantation. In the majority of these, tissue was transplanted onto the remaining ovary. Although grafting to a non-ovarian, non-pelvic, sub-peritoneal abdominal site has resulted in births, it has been suggested that compromised outcomes may be expected from a non-pelvic site.

STUDY DESIGN, SIZE, DURATION

The aim of the study was to assess the outcome from cryopreserved ovarian tissue transplanted to a site out of the pelvic area; a sub-peritoneal abdominal site. These outcomes were compared to transplantation to the ovary and peritoneal pelvic area in a cohort of 17 fertility preservation women where the individual sites of follicle aspiration were known and subsequent outcomes tracked. Ovarian tissue was slow frozen using the cryoprotectants propanediol and sucrose (n = 16 women) or using dimethyl sulfoxide and sucrose (n = 1 woman). Tissue was kept at 4°C overnight prior to freezing for 1 case. Tissue was thawed appropriately and prepared on 6.0 vicryl sutures for transplantation. Tissue was placed laparoscopically into a sub-peritoneal abdominal site, a pelvic side wall peritoneal pocket and the ovary.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Following resumption of cycling, gonadotrophin stimulation commenced with FSH, LH and antagonist and a trigger was given when one follicle was >13 mm in diameter. Abdominal follicles were aspirated under ultrasound guidance trans-abdominally; ovarian and pelvic follicles were aspirated trans-vaginally. Due to an inability to differentiate pelvic from ovarian follicles at the time of ultrasound-guided oocyte retrieval, both were classified as ovarian on the side where both were present. However, on the side, where no ovary was present, outcomes from pelvic follicles were reported.

MAIN RESULTS AND THE ROLE OF CHANCE

Average time lapse between ovarian tissue harvest and graft was 6 years. Resumption of cycling occurred on average 4.2 months post first graft, regardless of graft site. Mean follicle diameter on the day of oocyte aspiration was 14 mm for all sites. Aspiration failed to retrieve an oocyte in 30% (36/120) of abdominal follicles which was similar to the other sites; ovarian 24% (21/87), pelvic 32% (31/97). A similar proportion of retrieved oocytes was mature from all sites (67% (50/75) abdominal, 68% (42/62) ovarian, 59% (34/58) pelvic). The proportion of embryos which developed on Day 2 from those fertilized was also similar in all groups (90% (34/38) abdominal, 76% (22/29) ovarian, 96% (22/23) pelvic). To our knowledge, this is the first report of outcomes from cryopreserved ovarian tissue transplanted to a sub-peritoneal abdominal site and the subsequent comparison to outcomes from the ovary and a sub-peritoneal pelvic graft, within the same cohort of patients, where tissue was slow frozen predominantly with the cryoprotectant propanediol and sucrose.

LIMITATIONS, REASONS FOR CAUTION

The study reports outcomes from a small number of women following ovarian tissue transplantation. Follicle density is an estimate only and the amount of tissue grafted varied between patients.

WIDER IMPLICATIONS OF THE FINDINGS

The demonstration of successful outcomes from cryopreserved ovarian tissue grafted to a sub-peritoneal abdominal site has significant implications for the management of women in which grafting to pelvic sites is contraindicated although it appears to be important to trigger follicle maturation at a lower than normal follicular diameter. The relative ease of oocyte retrieval at the sub-peritoneal abdominal site also has positive implications for the introduction of this approach into clinical practice.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was used. All authors have no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Ovarian tissue damage after grafting: systematic review of strategies to improve follicle outcomes

Frozen-thawed human ovarian tissue endures large-scale follicle loss in the early post-grafting period, characterized by hypoxia lasting around 7 days. Tissue revascularization occurs progressively through new vessel invasion from the host and neoangiogenesis from the graft. Such reoxygenation kinetics lead to further potential damage caused by oxidative stress. The aim of the present manuscript is to provide a systematic review of proangiogenic growth factors, hormones and various antioxidants administered in the event of ovarian tissue transplantation to protect the follicle pool from depletion by boosting revascularization or decreasing oxidative stress. Although almost all investigated studies revealed an advantage in terms of revascularization and reduction in oxidative stress, far fewer demonstrated a positive impact on follicle survival. As the cascade of events driven by ischaemia after transplantation is a complex process involving numerous players, it appears that acting on specific molecular mechanisms, such as concentrations of proangiogenic growth factors, is not enough to significantly mitigate tissue damage. Strategies exploiting the activated tissue response to ischaemia for tissue healing and remodelling purposes, such as the use of antiapoptotic drugs and adult stem cells, are also discussed in the present review, since they yielded promising results in terms of follicle pool protection.

Modulating hypoxia and oxidative stress in human xenografts using adipose tissue-derived stem cells

OBJECTIVE

To investigate whether adipose tissue-derived stem cells (ASCs) modulate hypoxia and oxidative stress in human ovarian tissue transplants.

DESIGN

Prospective experimental study SETTING: Gynecological research unit in a university hospital PATIENT(S): Cryopreserved ovarian cortex from 5 adult women.

INTERVENTION(S)

Thirty mice were grafted with frozen-thawed human ovarian tissue, with or without ASCs (2-step/ASCs+ovarian tissue [OT] group and OT group). The ovarian grafts were retrieved on days 3 (n = 5), 10 (n = 5), and 21 (n = 5). The 10 animals grafted for 21 days underwent in vivo evaluations using microdialysis. One piece of ovarian tissue per patient was fixed for analysis after thawing (non-grafted controls).

MAIN OUTCOME MEASURE(S)

Direct reactive oxygen species were collected every second day after grafting by means of microdialysis. Analyses of ovarian fragments included immunolabeling for double CD34 (revascularization by host and graft components); immunofluorescence for hypoxia-inducible factor 1α (hypoxia-related response), nuclear factor erythroid 2-related factor 2 (oxidative stress-related response), and 8-hydroxy-deoxyguanosine (oxidative stress-related DNA damage); and gene expression (quantitative reverse transcription polymerase chain reaction) for vascular endothelial growth factor-A (neoangiogenesis), superoxide dismutase 2 (antioxidant activity), and nuclear respiratory factor 1 (mitochondrial biogenesis).

RESULT(S)

Reactive oxygen species peaked earlier in the ASC group (day 2) compared with that in the OT group (day 10) after grafting. Total vascularization was stable in the ASC group at all time points, while it was lower in the OT group 3 days after grafting. Hypoxia-inducible factor 1α expression, also detected in non-grafted controls, was significantly lower in the ASC group than in the OT group on days 3 and 10. The increase in VEGF gene expression lasted significantly longer in the ASC group than in the OT group. There was no significant upturn in the oxidative stress-related response (nuclear factor erythroid 2-related factor 2 pathway) or oocyte DNA damage (8-hydroxy-deoxyguanosine) in any of the grafted groups.

CONCLUSION(S)

Use of ASCs allows faster ovarian graft reperfusion and mitigates the hypoxia-related response through rapid revascularization, sustained by prolonged increase in vascular endothelial growth factor after grafting. No evidence of oxidative stress-related damage was detected irrespective of the transplantation strategy.

Building Organs Using Tissue-Specific Microenvironments: Perspectives from a Bioprosthetic Ovary

Recent research in tissue engineering and regenerative medicine has elucidated the importance of the matrisome. The matrisome, effectively the skeleton of an organ, provides physical and biochemical cues that drive important processes such as differentiation, proliferation, migration, and cellular morphology. Leveraging the matrisome to control these and other tissue-specific processes will be key to developing transplantable bioprosthetics. In the ovary, the physical and biological properties of the matrisome have been implicated in controlling the important processes of follicle quiescence and folliculogenesis. This expanding body of knowledge is being applied in conjunction with new manufacturing processes to enable increasingly complex matrisome engineering, moving closer to emulating tissue structure, composition, and subsequent functions which can be applied to a variety of tissue engineering applications.

Preservation of fertility in teenagers and young adults treated for haematological malignancies

As survival rates in teenagers and young adults diagnosed with haematological malignancies now exceed 70%, it is important that long-term quality of life, including measures to protect future fertility, are considered and discussed with patients and their families. Although discussion on the effect of planned cancer treatment on fertility is standard of care, knowledge of potential fertility treatment options and when they should be offered in haematological malignancies is not always so clear. In each case, the advice on the appropriate preservation of fertility depends upon a complex interplay of factors, weighing out the risk of future infertility against the risk of fertility preservation treatment, and recommendations must be made on a case-by-case basis. The aim of this Review is to evaluate the gonadotoxicity of treatments of prevalent haematological malignancies in teenagers and young adults, and provide an evidence-based framework to help with fertility discussion and management at the time of diagnosis, relapse or resistant disease, and in long-term follow-up settings.

Ovaries of patients recently treated with alkylating agent chemotherapy indicate the presence of acute follicle activation, elucidating its role among other proposed mechanisms of follicle loss

OBJECTIVE

To investigate mechanisms of primordial follicle (PMF) loss in vivo in human ovaries shortly after alkylating agent (AA) chemotherapy.

DESIGN

Cohort study.

SETTING

Tertiary university medical center.

PATIENT(S)

Ninety-six women aged 15-39 years who underwent ovarian tissue cryopreservation for fertility preservation.

INTERVENTION(S)

Fresh ovarian tissue samples were harvested from women treated with AA (n = 24) or non-AA (n = 24) chemotherapy <6 months after treatment and age-matched untreated women (n = 48).

MAIN OUTCOME MEASURE(S)

Differential follicle counts, time from chemotherapy exposure, immunostaining for apoptosis (cleaved caspase-3) and FOXO3A on tissue harvested within ultrashort time intervals (4-12 days), collagen (Sirius red) and neovascularization (CD34).

RESULT(S)

AA-treated ovaries had significant loss of PMFs, and significant increase in absolute numbers of growing follicles compared with untreated control ovaries. The number of growing follicles was inversely correlated with time from chemotherapy. Representative staining for FOXO3A observed decreased nuclear localization in PMF oocytes in AA-treated ovaries removed within the ultrashort time interval compared with untreated ovaries. Neither significant loss of PMFs, increase in growing follicles, nor decrease in nuclear FOXO3A were observed in non-AA-treated ovaries. No increased expression of cleaved caspase-3 was seen in PMFs within the ultrashort time interval after AA or non-AA chemotherapy. Significant stromal fibrosis and neovascularization were observed in AA-treated ovaries only after follicle loss had already occurred (4-6 months).

CONCLUSION(S)

Follicle activation occurs in vivo in ovaries of patients treated with AA, indicating a pathologic mechanism which may contribute to chemotherapy-induced follicle loss.

Fertility Preservation: The Challenge of Freezing and Transplanting Ovarian Tissue

Cancer treatments are increasingly effective, but can result in iatrogenic premature ovarian insufficiency. Ovarian tissue cryopreservation is the only option available to preserve fertility in prepubertal girls and young women who require immediate chemotherapy. Ovarian tissue transplantation has been shown to restore hormonal cycles and fertility, but a large proportion of the follicle reserve is lost as a consequence of exposure to hypoxia. Another crucial concern is the risk of reimplanting malignant cells together with the grafted tissue. In this review, the authors advance some challenging propositions, from prevention of chemotherapy-related gonadotoxicity to ovarian tissue cryopreservation and transplantation, including the artificial ovary approach.

Fertility Desires of Adolescent Females: Decreased Desire for Children in Those Identifying as Transgender/Gender Diverse and in Depressed Adolescents

STUDY OBJECTIVE

We aimed to describe fertility desires in healthy adolescent females and to explore associations of fertility desire with conditions and therapies potentially compromising fertility.

DESIGN

This was a cross-sectional, anonymous survey.

SETTING AND PARTICIPANTS

A total of 323 female adolescents aged 13-19 years were recruited from clinic waiting areas at a children's hospital. We oversampled on days when clinics serving adolescents with potential fertility compromise were scheduled.

MAIN OUTCOME MEASURES

We measured fertility desire by agreement with the statement "I want to have children someday." To measure compromised fertility we asked "In the past year, has a doctor, nurse or other medical professional ever talked to you about the possibility that you may have decreased fertility and may not be able to have your own biological child someday?" To measure depression severity, we used a validated scale, the PHQ-9, scores were dichotomized into no/mild and moderate/severe depression.

RESULTS

Mean age was 16.06 ± 1.87 years. Of the 323 participants, 57% identified as Hispanic, 24% as Black, 93.5% as cisgender, 6.5% as transgender/gender diverse, 70% as heterosexual, and 30% as sexual minority. A total of 35% had moderate/severe depression, and 12% had compromised fertility. Overall, 89% wanted children. Fewer transgender/gender diverse than cisgender participants wanted children (67% vs 93%, P < .001), as did fewer with moderate/severe versus no/mild depression (83% vs 93%, P < .05), whereas those with compromised fertility versus those without and heterosexual versus sexual minority participants had similar fertility desires. Transgender/gender diverse identity (odds ratio, 0.33; 95% confidence interval, 0.11-0.97; P < .05) and moderate/severe depression (odds ratio, 0.45; 95% confidence interval, 0.22-0.93; P < .05) were independently associated with lower fertility desire.

CONCLUSIONS

We found a high overall proportion of female adolescents desiring future children, and only 2 independent predictors of decreased fertility desire, namely, transgender/gender diverse identity and moderate/severe depression.

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.