Impact of breast cancer treatments on fertility and the importance of timing for a fertility preservation intervention

The increased survival achieved with surgery and cancer treatments for breast cancer has led to a growing concern about fertility in young women, adversely affecting quality of life outcomes. Th e potential loss of fertility not only has a psychological but can also affect patients' treatment adherence or decisions, such as selection of treatments associated with a lower risk of infertility despite inferior outcomes. Our objective is to provide an overview of current knowledge about how systemic cancer treatments could impact the future fertility of breast cancer survivors The main hypothesis of how chemotherapy produce damage to the ovaries is a direct damage to the DNA of the oocytes, resulting in the activation of apoptosis and / or autophagy-related pathways. Alkylating agents as cyclophosphamide are the chemotherapeutic agents that are associated with the highest risk of gonadotoxicity; however, breast cancer patients are usually given combinations of chemotherapy drugs. Conversely, endocrine therapy, such as tamoxifen, does not appear to have a permanent effect on fertility but long-term use could lower oocyte quality due to patient aging. There is still not enough evidence about the effect on ovarian reserve for many biological therapies and for new drugs being used in the non-metastatic setting, and further research in this area is needed. Members of multidisciplinary teams in breast cancer should understand the impact on fertility of cancer treatments and the importance of an early referral of premenopausal patients to specialists in reproductive medicine to discuss all possible fertility preservation strategies.