Fertility and ovarian function preservation in young women with breast cancer: A joint analysis of the Joven & Fuerte and PREFER prospective studies.

Background: Potential infertility and premature ovarian insufficiency represent notable concerns for young women with breast cancer (YWBC) undergoing chemotherapy. Cryopreservation techniques and temporary ovarian suppression with GnRH agonists (GnRHa) can be offered for fertility preservation (FP) and/or ovarian protection. This joint analysis of the Joven & Fuerte and PREFER multicenter prospective studies compared the uptake of these strategies and associated factors among Mexican and Italian YWBC.

Methods: Females ≤40 years diagnosed with non-metastatic BC from 2014 to 2019, who were offered FP strategies before (neo)adjuvant chemotherapy were included. Uptake of GnRHa for ovarian protection and cryopreservation procedures and reasons for their non-utilization were examined.

Results: Among 485 patients (74 % from Mexico; 26 % from Italy), cryopreservation techniques were used in 8 % of Mexican patients and 25 % of Italian patients (p < 0.001). Methods in Mexico and Italy, respectively, comprised oocyte (50 % and 87 %), embryo (53 % and 0 %), and ovarian tissue (0 % and 16 %) cryopreservation. GnRHa were used in 98 % of Italian patients and 6 % of Mexican patients. Cryopreservation uptake was associated with younger age (OR 1.2, 95 %CI 1.1-1.2), childlessness (OR 21.8, 95 %CI 10.0-47.6), stage I-II BC (OR 3.1, 95 %CI 1.5-6.3), private healthcare in Mexico (OR 3.0, 95 %CI 1.1-8.1), and unpartnered status in Italy (OR 5.4, 95 %CI 2.2-13.2).

Conclusion: FP and ovarian protection uptake were markedly higher in Italy than Mexico, possibly reflecting divergent social and healthcare contexts, though cryopreservation remained underutilized in both countries. Improved access to oncofertility services is warranted to provide comprehensive care aligned with the personal needs and life plans of YWBC.