Controlled ovarian stimulation outcomes of fertility preservation procedures in newly diagnosed breast cancer patients: a retrospective study from a single-tertiary-IVF centre

Abstract

The aim of this study was to evaluate the effectiveness of controlled ovarian stimulation (COS) using the letrozole-supplemented stimulation protocol in breast cancer (BC) patients prior to their cancer treatment. Sixty-one BC patients (Stages 0–3) who were referred to a university IVF unit for fertility preservation (FP) and underwent embryo and/or oocyte cryopreservation between 2008 − 2020 were included in this retrospective study. Time intervals between breast surgery and initial fertility consultation (IFC)/completion of FP procedures were evaluated. COS outcomes were assessed and compared between the early follicular phase (EFP) and the random-start (RS) protocols. The patients’ mean age was 33.3 ± 4.9 years. The mean time interval between breast surgery and IFC was 20.6 ± 11 (day, mean ± SD) and from IFC to completion of FP procedure was 14.7 ± 5.3. Overall, 9.1 ± 5.9 mature oocytes were obtained, with a peak serum oestradiol level of 388 ± 358 pg/mL. The number of oocytes obtained (11.5 ± 9.3 vs. 10.9 ± 6.9, p = .9) and maturation rates (84.3 ± 17.5% vs. 89.2 ± 11.7, p = .5) were not statistically different between the EPF and RS protocols. The study results support that oocyte or embryo freezing can be performed effectively in a limited time period with letrozole-supplemented COS protocols before the initiation of oncological treatments in breast cancer patients.

Impact statement

• What is already known on this subject? Currently, embryo and oocyte freezing are considered the most established fertility preservation (FP) methods for newly diagnosed cancer patients.

• What do the results of this study add? This study reports the COS outcomes of newly diagnosed breast cancer patients for FP over a period of twelve years from a single IVF unit. The results support that a considerable number of oocytes can be harvested with letrozole-supplemented COS protocol, which appears to be an effective protocol for BC patients.

• What are the implications of these findings for clinical practice and/or further research? There is a need for additional studies evaluating long-term follow-up of patients with their pregnancy outcomes.

Keywords:

• Breast cancer
• fertility preservation
• ovarian stimulation
• random start
• embryo cryopreservation

Disclosure statement

The authors declare that there is no conflict of interest.