A Novel Approach of Tracing in Vivo Bioluminescence Imaging Expression of Vitrified Immature Testicular Tissue Grafts Until Adulthood: A Translational Transgenic Mouse Model

Background: The optimal method for cryopreserving immature testicular tissue (ITT) remains unknown and there is no standardized protocol. Controlled slow freezing remains the mainstream method of choice in human prepubertal male fertility preservation. Currently, the outcomes for ITT vitrification are conflicting, and most data are limited to in vitro animal studies.Methods: A total of 12 pairs of donor and recipient mice were included in our experiments. The donors were immature transgenic mice, and the recipients were wild-type male mice. In the vitrification group, ITT was vitrified and thawed before transplantation. In the control group, ITT was transplanted to the recipients immediately. After thawing, we measured the expression of apoptosis-related mRNA caspase-3. More importantly, we monitored to adulthood all the transplanted grafts in vivo using noninvasive bioluminescence imaging (BLI) technology. On day 31, we removed the grafts for evaluation via hematoxylin and eosin staining and immunohistochemistry (IHC).Results: We traced the survival of the grafts by in vivo BLI on days 1, 2, 5, 7, and 31 after transplantation. In both the vitrification and the control groups, bioluminescence decreased between days 2 and 5. Subsequently, the bioluminescence showed an upward trend until day 31. Compared with day 1, the bioluminescence was significantly stronger on day 31 after transplantation (P = 0.009). The differences between the two groups were constantly insignificant after analysis. These results indicate that both fresh and frozen–thawed testicular tissues can survive for at least 31 days after transplantation. Moreover, the vitrification group showed BLI signals comparable with those of fresh tissues. Compared with the control group, expression of the caspase-3 gene was significantly increased after vitrification (P = 0.04). Histology and IHC showed that both tissue structure and protein expression were intact in both groups.Conclusions: Transplanted vitrified ITT grafts could survive till adulthood with BLI intensity comparable to that of the fresh control. Intact cells and structures for spermatogenesis in vitrified ITT grafts were as well-preserved as those in the control group. This translational model of self-repairing vitrified ITT grafts in vivo, lends weight to the role of vitrification in prepubertal male fertility preservation.

Oocyte cryopreservation review: outcomes of medical oocyte cryopreservation and planned oocyte cryopreservation

Background The utilization of oocyte cryopreservation (OC) has become popularized with increasing numbers of reproductive-aged patients desiring to maintain fertility for future family building. OC was initially used for fertility preservation in postmenarchal patients prior to gonadotoxic therapies; however, it is now available to patients to circumvent age-related infertility and other diagnoses associated with early loss of ovarian reserve. The primary aim of this paper is to provide a narrative review of the most recent and robust data on the utilization and outcomes of OC in both patient populations. Summary OC results in similar oocyte yield in patients facing gonadotoxic therapies and patients undergoing planned OC. Available data are insufficient to predict the live birth rates or the number of oocytes needed to result in live birth. However, oocyte yield and live birth rates are best among patients < 37.5 years old or with anti-mullerian hormone levels > 1.995 ng/dL, at the time of oocyte retrieval. There is a high ‘no use’ rate (58.9%) in patients using planned OC with 62.5% returning to use frozen oocytes with a spouse. The utilization rate in medical OC patients is < 10%. There is currently no data on the effects of BMI, smoking, or ethnicity on planned OC outcomes. Conclusion It is too early to draw any final conclusions on outcomes of OC in medical OC and planned OC; however, preliminary data supports that utilization of OC in both groups result in preservation of fertility and subsequent live births in patients who return to use their cryopreserved eggs. Higher oocyte yield, with fewer ovarian stimulation cycles, and higher live birth rates are seen in patients who seek OC at younger ages, reinforcing the importance of age on fertility preservation. More studies are needed in medical OC and planned OC to help guide counseling and decision-making in patients seeking these services.

Usefulness of random-start progestin-primed ovarian stimulation for fertility preservation

Background Progestin-primed ovarian stimulation (PPOS) has been used in infertility cases in recent years, and several reports have stated that it has oocyte collection results similar to those of gonadotropin-releasing hormone antagonist (GnRH-ant) protocol. For emergency fertility preservation, random-start ovarian stimulation is usually recommended. Therefore we compared the clinical outcomes of random-start PPOS with those of conventional random-start GnRH-ant protocols in fertility-preserving cases. Methods We retrospectively examined 86 cycles of oocyte collection, of which 56 were random-start GnRH-ant and 30 were random-start PPOS for fertility preservation at our hospital between January 2016 and April 2021. The primary outcome was the number of mature oocytes per cycle. The secondary outcome was the number of vitrified blastocysts per cycle for embryo freezing cases. Results No significant differences were noted in the number of days of stimulation, total dose of gonadotropin preparation, and the number of mature oocytes and vitrified blastocysts. The number of hospital visits for monitoring was significantly lower in the PPOS group. The start of menstruation before oocyte collection was significantly less in the PPOS group. Conclusions Random-start PPOS and GnRH-ant were similar in oocyte collection results. PPOS can reduce the number of hospital visits, thus reducing patient stress. PPOS at the start of the luteal phase can prevent the start of menstruation during ovarian stimulation.

Fertility preservation for transgender children and young people in paediatric healthcare: a systematic review of ethical considerations

BackgroundWhile fertility preservation is recommended practice for paediatric oncology patients, it is increasingly being considered for transgender children and young people in paediatric care. This raises ethical issues for clinicians, particularly around consent and shared decision-making in this new area of healthcare.MethodsA systematic review of normative literature was conducted across four databases in June 2020 to capture ethical considerations related to fertility counselling and preservation in paediatric transgender healthcare. The text of included publications was analysed inductively, guided by the Qualitative Analysis Guide of Leuven.ResultsTwenty-four publications were identified for inclusion. Four key ethical considerations emerged from this literature: access to fertility preservation, conscientious objection, decision-making capacity of children and young people, and shared decision-making.ConclusionIn the identified literature, there is consensus that transgender children and young people should not be refused access to fertility preservation services solely due to their gender identity, and that clinicians with conscientious objections to fertility preservation for this group have an obligation to refer on to willing providers. Factors that create ethical complexity in this area of paediatric care include the child’s age, mental health, and parents’ views.