Cryopreservation of ovarian tissue after pretreatment with a gonadotropin-releasing hormone agonist

Ovarian tissue cryopreservation in Malaysia: a case series

OBJECTIVES

We aim to discuss the hematological cancer cases that opted for ovarian tissue cryopreservation (OTC) as fertility preservation before the gonadotoxic chemotherapy agent.

CASE PRESENTATION

The ovarian tissue cryopreservation (OTC) was started in August 2020 in our center. Up to now, there were four cases have been performed and included in this report. The ovarian tissue cortex was cryopreserved with cryoprotectant using Kitazato™ (Tokyo, Japan) media and fit in the closed system devices. A total of four post-OTC patients were included. The mean age was 24 years old, whereas the mean serum AMH level was 30.43 pmol/L. Most of them were diagnosed with lymphoma, except one was leukemia. All of them received additional GnRH analog following OTC as a chemoprotective agent before cancer treatment. Currently, they are recovering well and on regular follow-up with the hematological department.

CONCLUSIONS

Although The OTC is an ultimate option for prepubertal girls, it can be proposed as a good strategy for adult cancer women who could not delay cancer therapy.

Assessment of long-term function of heterotopic transplants of vitrified ovarian tissue in cynomolgus monkeys

BACKGROUND

Ovarian tissue cryopreservation by rapid cooling (vitrification) is a convenient fertility preservation option. However, the progress of vitrified ovarian tissue after transplantation is not well understood in primates.

METHODS

For tissues from cynomolgus monkeys, we used closed straw vitrification and open cryosupport vitrification in which tissues are immersed directly into liquid nitrogen. Following warming, ovarian cortical pieces were autotransplanted and their function was monitored by computed tomography (CT), hormone assays and oocyte recovery, ICSI and embryo transfers (ETs).

RESULTS

Hormone cycles were restored in 6 of 7 animals in a mean of 126 days with no significant difference between the two vitrification regimens. The presence of new blood vessels supplying the grafted ovarian tissue was confirmed by contrast-enhanced CT. Oocyte retrieval from two monkeys after transplantation of the ovarian cortex vitrified by cryosupport vitrification yielded a total of nine oocytes of which six fertilized after ICSI, but ETs did not lead to any pregnancies.

CONCLUSIONS

This work shows that CT can give insight into ovarian function after heterotopic transplantation, and that heterotopic autografts of vitrified ovarian cortex can give rise to long-term ovarian function and embryos in a primate model. It remains to be established how outcomes following rapid vitrification compared with outcomes following conventional slow cooling procedures.