When to cryopreserve ovarian tissue: effects of chemotherapy on the ovarian reserve by studying follicular density and apoptosis.

OBJECTIVES
Patients scheduled to receive chemotherapy should be counseled on fertility preservation. Known gonadotoxic chemotherapies such as alkylating agents have a high risk of altering ovarian reserve. In some cases, the urgency of treatment requires the use of chemotherapy before fertility preservation, which will be carried out at a later stage. Most often the ovarian tissue is cryopreserved. The aim of our study is to investigate the impact of chemotherapies on follicular density and apoptosis of reserve follicles.


METHODS
We included 140 patients: 63 patients, mean age 18.8 years, were included in the group no chemotherapy (group A) and 77 patients, mean age 17.1 years, in the group presence of chemotherapy before ovarian conservation (group B). None of the patients had had pelvic radiotherapy prior to ovarian cryopreservation. The histological parameters studied were: follicular density and the presence of malignant cells. We selected 12 patients from group A and 15 patients from group B, comparable in age and pathology, for whom we evaluated follicle apoptosis by immunostaining cleaved caspase 3.


RESULTS
We demonstrated an inverse relationship between follicular density and age (p<0.0001), as well as a lack of effect of chemotherapy on follicular density (p=0.87). We showed an impact of chemotherapies, especially alkylating agents, on the apoptosis of ovarian follicles (p<0.0001). 3 patients had ovarian tissue infiltration, 2 of which were malignant.


CONCLUSION
This work underlines that conservation of ovarian tissue after chemotherapy remains possible.