Reproductive outcomes after in vitro fertilization treatment in a cohort of Danish women transplanted with cryopreserved ovarian tissue

Utility and Outcomes of Ovarian Tissue Cryopreservation and Transplantation for Gynecologic Cancers: A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the utility, success, and safety of ovarian tissue cryopreservation and autologous cryopreserved ovarian tissue transplantation for fertility preservation in patients with gynecologic cancers.

DATA SOURCES

A comprehensive search was performed of the MEDLINE, EMBASE, ClinicalTrials.gov , and Cochrane Library databases to identify relevant studies on the utility and outcomes of ovarian tissue cryopreservation and autologous cryopreserved ovarian tissue transplantation for gynecologic cancers from inception until January 23, 2024.

METHODS OF STUDY SELECTION

Two reviewers independently performed the study selection, data extraction, and risk-of-bias assessment, and the results were then reviewed together. Twenty-three studies were included in the current systematic review.

TABULATION, INTEGRATION, AND RESULTS

The resultant data were meta-analyzed to produce a pooled-effect estimate of the utility of ovarian tissue cryopreservation and autologous transplantation in gynecologic cancers as a proportion of all indications. We found that 7.5% and 9.6% of women undergoing ovarian tissue cryopreservation and autologous transplantation, respectively, had gynecologic cancers. In comparison, hematologic malignancies and breast cancer accounted for approximately 66.0% of all indications for these procedures. The return rate for autologous cryopreserved ovarian tissue transplantation in gynecologic cancers (6.0%) was not statistically different from those for other indications. Among women with gynecologic cancer who underwent ovarian stimulation, 27.3% had at least one child, and the ovarian endocrine function was restored in 78.1% of the women after autologous transplantation. The median graft longevity was 32 months, and no graft-site recurrence was reported after autologous transplantation in women with gynecologic cancer.

CONCLUSION

Our results suggest that ovarian tissue cryopreservation and autologous transplantation are feasible options for preserving ovarian function in women with gynecologic cancers, although ovarian tissue cryopreservation is underutilized, and further studies are needed to determine the longer-term outcomes of autologous transplantation.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42024498522.

Current practices in oncofertility counseling: updated evidence on fertility preservation and post-treatment pregnancies in young women affected by early breast cancer

INTRODUCTION

Anticancer treatments have significantly contributed to increasing cure rates of breast cancer in the last years; however, they can also lead to short- and long-term side effects, including gonadotoxicity, and compromised fertility in young women. Oncofertility is a crucial issue for young patients who have not yet completed their family planning at the time of cancer diagnosis.

AREAS COVERED

This review aims to cover all the latest available evidence in the field of oncofertility, including the gonadotoxicity of currently adopted anticancer therapies in the curative breast cancer setting, the available strategies for fertility preservation and the feasibility of achieving a pregnancy following anticancer treatment completion.

EXPERT OPINION

Over the past years, a significant progress has been made in oncofertility care for young women with breast cancer. In the context of the currently available evidence, every young woman with newly diagnosed breast cancer should receive a proper and complete oncofertility counseling before starting any anticancer treatment to increase her chances of future pregnancies.

Safety of ovarian cryopreservation and transplantation in patients with acute leukemia: a case series

BACKGROUND

With increased success, ovarian tissue cryopreservation has recently become a standard technique for fertility preservation. However, malignant cell introduction through ovarian tissue transplantation remains a major concern for patients with acute leukemias.

OBJECTIVE

This study aimed to investigate the safety of performing autologous ovarian tissue transplantation in survivors of acute leukemia.

STUDY DESIGN

Clinical, histopathological, and molecular data of 4 women with acute myeloid leukemia and 2 women with acute lymphoblastic leukemia who underwent ovarian tissue cryopreservation and transplantation were analyzed in this case series. Following cryopreservation of 66% to 100% of an ovarian cortex with a slow freezing method, all women received high-dose multiagent alkylating preconditioning chemotherapy for allogeneic hematopoietic stem cell transplantation. Before the ovarian tissue transplantation, (1) antral follicle counts, serum antimüllerian hormone and follicle-stimulating hormone levels were assessed to confirm primary ovarian insufficiency; (2) all recipients were cleared by their hematologist-oncologists; (3) representative cortical strips were screened for leukemia infiltration by histologic (hematoxylin and eosin staining), immunohistochemical (CD3, CD20, CD34, CD68, CD117, CD163, PAX-5, Tdt, lysozyme, and MPO), and molecular marker evaluation (BCR/ABL p190 and AML1/ETO) where appropriate.

RESULTS

The median age was 20 years (interquartile range, 15-32) at ovarian tissue cryopreservation. Before undergoing hematopoietic stem cell transplantation, all patients received induction or consolidation chemotherapy that included cytarabine + daunorubicin or Berlin-Frankfurt-Munich-95 protocol and were in remission. The mean serum antimüllerian hormone was 1.9±1.7 ng/mL before ovarian tissue cryopreservation. In all cases, ovarian tissue screening for leukemic cells was negative. Ovarian transplantation was performed laparoscopically with or without robotic assistance, after a median of 74.5 months (interquartile range, 41-120) after ovarian tissue cryopreservation. Ovarian function resumed in all patients after a median of 3.0 months (range, 2.5-4.0), and 2 women had 1 live birth each. The median graft longevity was 35.5 months (interquartile range, 18-57) after ovarian tissue transplantation. After a median follow-up of 51 months (interquartile range, 20-74), all patients remained relapse-free. In 1 patient, the graft was removed during cesarean delivery and was negative for immunochemical leukemia markers.

CONCLUSION

Our long-term follow-up demonstrated no evidence of disease relapse after ovarian tissue transplantation in patients with acute leukemia who received allogeneic hematopoietic stem cell transplantation. This safety profile may be explained by the fact that these patients are induced into remission by nongonadotoxic induction chemotherapy before undergoing ovarian tissue cryopreservation. We propose that ovarian tissue cryopreservation should not be excluded as a fertility preservation option for young women with leukemia who are due to receive preconditioning chemotherapy before allogeneic hematopoietic stem cell transplantation.

Assessing the impact of transplant site on ovarian tissue transplantation: a single-arm meta-analysis

BACKGROUND

Survival rates of young women undergoing cancer treatment have substantially improved, with a focus on post-treatment quality of life. Ovarian tissue transplantation (OTT) is a viable option to preserve fertility; however, there is no consensus on the optimal transplantation site. Most studies on OTT are nonrandomized controlled trials with limited sample sizes and uncontrolled statistical analyses, leaving the question of which transplant site yields the highest chance of achieving a live birth unanswered.

OBJECTIVE

This meta-analysis aimed to assess the effect of different ovarian transplant sites on postoperative reproductive outcomes.

METHODS

We adhered to the PRISMA Reporting Items for Systematic Reviews and Meta-Analyses recommendations. Systematic searches were conducted in PubMed, Embase, Web of Science, and the Cochrane Library from inception to September 17, 2023. The inclusion criteria were as follows: (1) women who underwent OTT with a desire for future childbirth, and (2) reports of specific transplant sites and corresponding pregnancy outcomes. The exclusion criteria included the inability to isolate or extract relevant outcome data, case reports, non-original or duplicate data, and articles not written in English.

RESULTS

Twelve studies (201 women) were included in the meta-analysis of cumulative live birth rates (CLBR) after OTT. The CLBR, which encompasses both spontaneous pregnancies and those achieved through assisted reproductive technology (ART) following OTT to the ovarian site, was 21% (95% CI: 6-40, I2: 52.81%, random effect). For transplantation to the pelvic site, the live birth rate was 30% (95% CI: 20-40, I2: 0.00%, fixed effect). Combining transplantation to both the pelvic and ovarian sites resulted in a live birth rate of 23% (95% CI: 11-36, I2: 0.00%, fixed effect). Notably, heterotopic OTT yielded a live birth rate of 3% (95% CI: 0-17, I2: 0.00%, fixed effect).

CONCLUSION

Pregnancy outcomes were not significantly different after orthotopic ovarian transplantation, and pregnancy and live birth rates after orthotopic OTT were significantly higher than those after ectopic transplantation.

REGISTRATION NUMBER

INPLASY202390008.

Effects of needle puncturing on re-vascularization and follicle survival in xenotransplanted human ovarian tissue

BACKGROUND

Ovarian tissue transplantation can restore fertility in young cancer survivors, however the detrimental loss of follicles following transplantation of cryopreserved ovarian tissue is hampering the efficiency of the procedure. This study investigates whether needle puncturing prior to transplantation can enhance revascularization and improve follicle survival in xenotransplanted human ovarian cortex.

METHODS

Cryopreserved human ovarian cortex pieces (N = 36) from 20 women aged 24-36 years were included. During the thawing process, each piece of tissue was cut in halves; one half serving as the untreated control and the other half was punctured approximately 150-200 times with a 29-gauge needle. The cortex pieces were transplanted subcutaneously to immunodeficient mice for 3, 6 and 10 days (N = 8 patients) and for 4 weeks (N = 12 patients). After 3, 6 and 10 days, revascularization of the ovarian xenografts were assessed using immunohistochemical detection of CD31 and gene expression of angiogenic factors (Vegfα, Angptl4, Ang1, and Ang2), and apoptotic factors (BCL2 and BAX) were performed by qPCR. Follicle density and morphology were evaluated in ovarian xenografts after 4 weeks.

RESULTS

A significant increase in the CD31 positive area in human ovarian xenografts was evident from day 3 to 10, but no significant differences were observed between the needle and control group. The gene expression of Vegfα was consistently higher in the needle group compared to control at all three time points, but not statistically significant. The expression of Ang1 and Ang2 increased significantly from day 3 to day 10 in the control group (p < 0.001, p = 0.0023), however, in the needle group this increase was not observed from day 6 to 10 (Ang2 p = 0.027). The BAX/BCL2 ratio was similar in the needle and control groups. After 4-weeks xenografting, follicle density (follicles/mm³, mean ± SEM) was higher in the needle group (5.18 ± 2.24) compared to control (2.36 ± 0.67) (p = 0.208), and a significant lower percentage of necrotic follicles was found in the needle group (19%) compared to control (36%) (p = 0.045).

CONCLUSIONS

Needle puncturing of human ovarian cortex prior to transplantation had no effect on revascularization of ovarian grafts after 3, 6 and 10 days xenotransplantation. However, needle puncturing did affect angiogenic genes and improved follicle morphology.

Live birth rate after female fertility preservation for cancer or haematopoietic stem cell transplantation: a systematic review and meta-analysis of the three main techniques; embryo, oocyte and ovarian tissue cryopreservation

STUDY QUESTION

What are the chances of achieving a live birth after embryo, oocyte and ovarian tissue cryopreservation (OTC) in female cancer survivors?

SUMMARY ANSWER

The live birth rates (LBRs) following embryo and oocyte cryopreservation are 41% and 32%, respectively, while for IVF and spontaneous LBR after tissue cryopreservation and transplantation, these rates are 21% and 33%, respectively.

WHAT IS KNOWN ALREADY

Currently, fertility preservation (FP) has become a major public health issue as diagnostic and therapeutic progress has made it possible to achieve an 80% survival rate in children, adolescents and young adults with cancer. In the latest ESHRE guidelines, only oocyte and embryo cryopreservation are considered as established options for FP. OTC is still considered to be an innovative method, while it is an acceptable FP technique in the American Society for Reproductive Medicine guidelines. However, given the lack of studies on long-term outcomes after FP, it is still unclear which technique offers the best chance to achieve a live birth.

STUDY DESIGN, SIZE, DURATION

We performed a systematic review and meta-analysis of published controlled studies. Searches were conducted from January 2004 to May 2021 in Medline, Embase and the Cochrane Library using the following search terms: cancer, stem cell transplantation, FP, embryo cryopreservation, oocyte vitrification, OTC and reproductive outcome.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 126 full-text articles were preselected from 1436 references based on the title and abstract and assessed via the Newcastle-Ottawa Quality Assessment Scale. The studies were selected, and their data were extracted by two independent reviewers according to the Cochrane methods. A fixed-effect meta-analysis was performed for outcomes with high heterogeneity.

MAIN RESULTS AND THE ROLE OF CHANCE

Data from 34 studies were used for this meta-analysis. Regarding cryopreserved embryos, the LBR after IVF was 41% (95% CI: 34-48, I2: 0%, fixed effect). Concerning vitrified oocytes, the LBR was 32% (95% CI: 26-39, I2: 0%, fixed effect). Finally, the LBR after IVF and the spontaneous LBR after ovarian tissue transplantation were 21% (95% CI: 15-26, I2: 0%, fixed-effect) and 33% (95% CI: 25-42, I2: 46.1%, random-effect), respectively. For all outcomes, in the sensitivity analyses, the maximum variation in the estimated percentage was 1%.

LIMITATIONS, REASONS FOR CAUTION

The heterogeneity of the literature prevents us from comparing these three techniques. This meta-analysis provides limited data which may help clinicians when counselling patients.

WIDER IMPLICATIONS OF THE FINDINGS

This study highlights the need for long-term follow-up registries to assess return rates, as well as spontaneous pregnancy rates and birth rates after FP.

STUDY FUNDING/COMPETING INTEREST(S)

This work was sponsored by an unrestricted grant from GEDEON RICHTER France. The authors have no competing interests to declare.

REGISTRATION NUMBER

CRD42021264042.

Reproductive and Endocrine Outcomes in a Cohort of Danish Women following Auto-Transplantation of Frozen/Thawed Ovarian Tissue from a Single Center

Ovarian tissue cryopreservation (OTC) is a method of fertility preservation in girls and young women prior to gonadotoxic treatment. It is a safe and promising method to restore fertility. The initial recovery of endocrine function is high, but the longevity of the grafted tissue varies. In this single-center, combined retro- and prospective cohort study, we report the reproductive outcome and hormonal recovery following ovarian tissue transplantation (OTT) and evaluate possible predictors of the chance of pregnancy. The study includes 40 women from eastern Denmark undergoing 53 OTTs between 2003 and 2021. Permission to obtain retrospective data was given by the Danish Patient Safety Authorities and prospective data-collection by informed consent. Initial recovery of endocrine function was seen in 18/19 women with POI, and ongoing function of the grafted tissue in 7/14 two years from OTT. Live birth rate (LBR) was 41%, with 20 children to 39 women trying to conceive. Women who conceived had higher AFC at the time of OTC than women who did not (p ± 0.04). Repeated transplantations were not successful in terms of delivery. Half of all pregnancies were achieved by ART, but PRs were lower after ART than by spontaneous conception. LBRs after OTT are encouraging. Chance of pregnancy after OTT is correlated to ovarian reserve at OTC. Repeated transplantations were not successful in terms of unfulfilled pregnancy wish.

A synopsis of global frontiers in fertility preservation

Since 2007, the Oncofertility Consortium Annual Conference has brought together a diverse network of individuals from a wide range of backgrounds and professional levels to disseminate emerging basic and clinical research findings in fertility preservation. This network also developed enduring educational materials to accelerate the pace and quality of field-wide scientific communication. Between 2007 and 2019, the Oncofertility Consortium Annual Conference was held as an in-person event in Chicago, IL. The conference attracted approximately 250 attendees each year representing 20 countries around the world. In 2020, however, the COVID-19 pandemic disrupted this paradigm and precluded an in-person meeting. Nevertheless, there remained an undeniable demand for the oncofertility community to convene. To maintain the momentum of the field, the Oncofertility Consortium hosted a day-long virtual meeting on March 5, 2021, with the theme of "Oncofertility Around the Globe" to highlight the diversity of clinical care and translational research that is ongoing around the world in this discipline. This virtual meeting was hosted using the vFairs ® conference platform and allowed over 700 people to participate, many of whom were first-time conference attendees. The agenda featured concurrent sessions from presenters in six continents which provided attendees a complete overview of the field and furthered our mission to create a global community of oncofertility practice. This paper provides a synopsis of talks delivered at this event and highlights the new advances and frontiers in the fields of oncofertility and fertility preservation around the globe from clinical practice and patient-centered efforts to translational research.

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.

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.

Ovarian transplantation with robotic surgery and a neovascularizing human extracellular matrix scaffold: a case series in comparison to meta-analytic data

OBJECTIVE

To report our experience with robot-assisted (RA) autologous cryopreserved ovarian tissue transplantation (ACOTT) with the use of a neovascularizing extracellular matrix scaffold.

DESIGN

Case series with meta-analytic update.

SETTING

Academic.

PATIENT(S)

Seven recipients of RA-ACOTT.

INTERVENTION(S)

Before or shortly after initiating chemotherapy, ovarian tissue was cryopreserved from 7 women, who then underwent RA-ACOTT 9.9 ± 1.8 years (range, 7-12 years) later. Perioperatively, they received transdermal estrogen and low-dose aspirin to enhance graft vascularization. Ovarian cortical pieces were thawed and sutured on an extracellular matrix scaffold, which was then robotically anastomosed to the bivalved remaining ovary in 6 cases and retroperitoneally (heterotopic) to the lower abdomen in 1 case.

MAIN OUTCOME MEASURE(S)

Ovarian function return, the number of oocytes/embryos, aneuploidy %, live births, and neonatal outcomes were recorded. Graft longevity was compared with the mean from the meta-analytic data.

RESULT(S)

Ovarian function returned 13.9 ± 2.7 weeks (11-16.2 weeks) after ACOTT, and oocytes were retrieved in all cases with 12.3 ± 6.9 embryos generated. In contrast to orthotopic, the heterotopic ACOTT demonstrated low embryo quality and an 80% aneuploidy rate. A recipient did not attempt to conceive and 2 needed a surrogate, whereas 4 of 4 delivered 6 healthy children, compared with 115 of 460 (25% pregnancy rate) from the meta-analytic data (n = 79). The mean graft longevity (43.2 ± 23.6/47.4 ± 22.8 months with/without sensitivity analysis) trended longer than the meta-analytic mean (29.4 ± 22.7), even after matching age at cryopreservation.

CONCLUSION(S)

In this series, RA-ACOTT resulted in extended graft longevity, with ovarian functions restored in all cases, even when the tissues were cryopreserved after chemotherapy exposure.

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].

Reproductive issues in carriers of germline pathogenic variants in the BRCA1/2 genes: an expert meeting

BACKGROUND

Healthy individuals and patients with cancer who are carriers of germline pathogenic variants in the BRCA1/2 genes face multiple reproductive challenges that require appropriate counseling and specific expertise.

MAIN BODY

On December 5th-7th, 2019, patient advocates and physicians with expertise in the field of reproductive medicine, fertility preservation, and oncology were invited to "San Giuseppe Moscati" Hospital in Avellino (Italy) for a workshop on reproductive management of women with germline pathogenic variants in the BRCA1/2 genes. From the discussion regarding the current evidence and future prospective in the field, eight main research questions were formulated and eight recommendations were developed regarding fertility, fertility preservation, preimplantation genetic testing, and pregnancy in healthy carriers and patients with cancer.

CONCLUSION

Several misconceptions about the topic persist among health care providers and patients often resulting in a discontinuous and suboptimal management. With the aim to offer patient-tailored counseling about reproductive issues, both awareness of current evidences and research should be promoted.

Use of cryopreserved ovarian tissue in the Danish fertility preservation cohort

OBJECTIVE

To evaluate the use of cryopreserved ovarian tissue in the Danish fertility preservation cohort.

DESIGN

Retrospective cohort study.

SETTING

University hospitals and fertility clinics.

PATIENT(S)

Ovarian tissue cryopreservation (OTC) was performed for 1,186 Danish girls and women from 1999-2020, of whom 117 subsequently underwent ovarian tissue transplantation (OTT). Subgroup 1 included 759 patients with a follow-up period of >5 years. Out of these, OTT rates were further analyzed for those patients who were alive and aged >24 years in July 2020 (subgroup 2; n = 554).

INTERVENTION(S)

OTC and OTT.

MAIN OUTCOME MEASURE(S)

OTT, death, donation of tissue.

RESULT(S)

In subgroup 1, 14% of the patients had undergone OTT, 18% had died, 9% had donated their tissue for research, and 59% still had their tissue stored. In subgroup 2, 19% had undergone OTT and for most diagnoses the OTT rates ranged from 15% to 22% with benign hematologic diseases having the highest OTT rate (35%). On the basis of the entire cohort, stratified age analysis indicated that women aged ≥30 years at OTC were more likely to return for OTT than women aged 18-29 years at OTC; mean storage times were 3.7 and 3.6 years, respectively. Only 4% of the girls aged <18 years at OTC had undergone OTT.

CONCLUSION(S)

The OTT rates depended on the diagnosis, age at OTC, and follow-up time. Specific criteria are needed for reporting and comparing OTT rates. Six out of 10 patients still had their cryopreserved tissue stored and longer follow-up is needed, especially for younger girls.

N-acetylcysteine protects ovarian follicles from ischemia-reperfusion injury in xenotransplanted human ovarian tissue

STUDY QUESTION

Can antioxidant treatment with N-acetylcysteine (NAC) protect ovarian follicles from ischemia-reperfusion injury in xenotransplanted human ovarian tissue?

SUMMARY ANSWER

Daily administration of NAC for 7-12 days post-transplantation reduced ischemia-reperfusion injury and increased follicle survival in human ovarian xenografts by upregulating the antioxidant defense system and exerting anti-inflammatory and antiapoptotic effects.

WHAT IS KNOWN ALREADY

Freezing of human ovarian tissue is performed with high follicular survival rates but up to 70% of follicles appear to be lost due to hypoxia and ischemia-reperfusion injury during ovarian tissue transplantation (OTT). NAC has been demonstrated to possess antioxidant and antiapoptotic properties, and studies in rodents have shown that intraperitoneal administration of NAC reduces ischemia-reperfusion injury and increases follicle survival in autotransplanted murine ovaries.

STUDY DESIGN, SIZE, DURATION

Pieces of frozen-thawed human ovarian tissue from 28 women aged 23-36 years were transplanted to immunodeficient mice in short- and long-term xenograft studies or cultured in vitro. Three short-term xenograft studies (1-week duration) were performed, in which saline or 150 mg/kg NAC was administered for 7 days post-transplantation (n = 12 patients per group). Two long-term xenograft studies (4 weeks of duration) were performed. In one of these studies, saline or 150 mg/kg NAC was administered for 12 days (n = 12 patients per group), while in the other study 50, 150 or 300 mg/kg NAC was administered for 7 days (n = 8 patients per group). In addition, human ovarian tissue (n = 12 pieces from three patients per group) was cultured with increasing concentrations of NAC (0, 5, 25 and 75 mM) for 4 days in vitro.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Donated ovarian tissue was obtained from women who had undergone ovarian tissue cryopreservation for fertility preservation at the University Hospital of Copenhagen. Cortical tissue pieces (5 × 5 × 1 mm) were transplanted subcutaneously to immunodeficient mice and NAC or saline was injected intraperitoneally. Grafts were retrieved after 1 or 4 weeks and follicle density was assessed. Gene expression analysis of antioxidant defense markers (superoxide dismutase; Sod1/SOD1, heme oxygenase-1; Hmox1/HMOX1, catalase; Cat/CAT), proinflammatory cytokines (tumor necrosis factor-alpha; Tnf-α, interleukin-1-beta; Il1-β, interleukin 6; Il6), apoptotic factors (B-cell lymphoma 2; Bcl2/BCL2, Bcl-2-associated X protein; Bax/BAX) and angiogenic factors (vascular endothelial growth factor A; Vegfa/VEGFA, angiopoietin-like 4; Angptl4/ANGPTL4) was performed in 1-week-old human ovarian xenografts and in cultured human ovarian tissue. Grafts retrieved after 4 weeks were histologically processed and analyzed for vascularization by CD31 immunohistochemical staining, fibrosis by Masson's Trichrome staining and apoptosis by immunofluorescence using cleaved caspase-3.

MAIN RESULTS AND THE ROLE OF CHANCE

After 1-week grafting, the relative expression of Sod1, Hmox1 and Cat was significantly higher in the group receiving 150 mg/kg NAC (NAC150-treated group) compared to controls (P = 0.04, P = 0.03, and P = 0.01, respectively), whereas the expression levels of Tnf-α, Il1-β and Il6 were reduced. The Bax/Bcl2 ratio was also significantly reduced in the NAC150-treated group (P < 0.005). In vitro, the relative gene expression of SOD1, HMOX1 and CAT increased significantly in the human ovarian tissue with increasing concentrations of NAC (P < 0.001 for all genes). However, the expression of VEGFA and ANGPTL4 as well as the BAX/BCL2 ratio decreased significantly with increasing concentrations of NAC (P < 0.02, P < 0.001 and P < 0.001, respectively). After 4-week grafting, fibrosis measured by collagen content was similar in the NAC150-treated group compared to controls (control: 56.6% ± 2.2; NAC150: 57.6% ± 1.8), whereas a statistically significant reduction in the CD31-positive vessel area was found (control: 0.69% ± 0.08; NAC150: 0.51% ± 0.07; P < 0.02). Furthermore, a reduced immunoreactivity of cleaved caspase-3 was observed in follicles of the NAC150-treated xenografts compared to controls. Follicle density (follicles/mm3, mean ± SD) was higher in the NAC150-treated group compared to the control group in the 1-week xenografts (control: 19.5 ± 26.3; NAC150: 34.2 ± 53.5) and 4-week xenografts (control: 9.3 ± 11.0; NAC150: 14.4 ± 15.0). Overall, a 2-fold increase in follicle density was observed in the NAC150-group after 1-week grafting where fold changes in follicle density were calculated in relation to grafts from the same patient. Around a 5-fold increase in follicle density was observed in the NAC150 and NAC300 groups after 4-week grafting.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

Follicle density in the human ovarian cortex is highly heterogeneous and can vary 100-fold between cortex pieces from the same woman. A high variability in follicle density within and between treatment groups and patients was found in the current study. Thus, solid conclusions cannot be made. While intraperitoneal injections of NAC appeared to reduce ischemia-reperfusion injury in human ovarian xenografts, different administration routes should be investigated in order to optimize NAC for potential clinical use.

WIDER IMPLICATIONS OF THE FINDINGS

This is the first study to demonstrate the antioxidant, anti-inflammatory and antiapoptotic properties of NAC in xenotransplanted human ovarian tissue. Therefore, NAC appears to be a promising candidate for protecting ovarian follicles from ischemia-reperfusion injury. This provides the initial steps toward clinical application of NAC, which could potentially reduce the loss of ovarian follicles following OTT.

STUDY FUNDING/COMPETING INTEREST(S)

We are grateful to the Danish Childhood Cancer Foundation, Hørslev Foundation, Aase and Einar Danielsen's Foundation (grant number: 10-001999), Dagmar Marshalls Foundation, Else and Mogens Wedell-Wedellsborgs Foundation, Knud and Edith Eriksens Mindefond, and Fabrikant Einar Willumsens Mindelegat for funding this study. None of the authors have any competing interests to declare.

Efficacy of assisted reproductive technology after ovarian tissue transplantation in a cohort of 11 patients with or without associated infertility factors

PURPOSE

IVF treatment in women with grafted frozen-thawed ovarian tissue is associated with poor reproductive outcomes. The aim of this study was to evaluate the efficacy of ovarian tissue transplantation (OTT) followed by assisted reproductive technology (ART) in women with or without associated infertility factors.

METHODS

This is a prospective cohort study with retrospective data collection including eleven women, four of whom having an infertility factor (IF), who had undergone OTT in one university center between 2005 and 2017, followed by ART in six in vitro fertilization (IVF) centers.

RESULTS

In total, 25 of the 85 cycles initiated (29%) were canceled, resulting in 60 oocyte retrievals. Ninety-five oocytes were retrieved: 36 were abnormal or immature, 29/39 fertilized (74%) after ICSI and 13/20 (65%) after IVF. Thirty-five embryos were transferred in seven patients (5/7 patients without IF and 2/4 patients with IF). After ART, one patient with IF experienced two pregnancies, one resulting in a live birth. For all patients, pregnancy rates and live birth rates were 7.4% and 3.7% per embryo transfer, respectively. Nine pregnancies and four live births occurred after spontaneous conception in five patients without IF, none in the infertility group.

CONCLUSION

This study confirms that IVF treatment in women with grafted frozen-thawed ovarian tissue is associated with poor outcomes. However, the chances of natural conception are high in women without IF. Patients with IF, without the possibility of spontaneous pregnancy, should be informed of poor reproductive outcomes after OTT followed by ART.

TRIAL REGISTRATION NUMBER

NCT02184806.