Bases fisiológicas, técnicas y principales indicaciones de preservación de la fertilidad en la paciente oncológica

In recent decades, the use of fertility preservation techniques in women with oncologic pathology has increased, aiming to improve their future reproductive prognosis. This trend is attributed to the increasing incidence of neoplasms in women of reproductive age, improved survival rates, and the progressive delay of motherhood. The gonadotoxicity of chemotherapy is influenced by factors like the patient's age, baseline ovarian reserve, and the type and cumulative dose of chemotherapy. Therefore, it is crucial to provide appropriate reproductive counseling and refer patients to specialized fertility preservation programs, where comprehensive assessment of gonadotoxic risk and individual patient risk are performed. Oocyte cryopreservation is the main technique for fertility preservation, non-experimental since 2013. Controlled ovarian stimulation starts at any phase of the menstrual cycle (random start), avoiding the delay in starting chemotherapy. In addition, the treatment with letrozole is recommended to breast cancer patients performing ovarian stimulation to prevent excessive increases in serum estrogen levels. The ovarian cortex cryopreservation is still considered experimental in many countries. However, it is performed in some cases, for example, when chemotherapy cannot be delayed for 2 weeks or in prepubertal patients. At the present time, gonadotropin-releasing hormone (GnRH) treatment is not regarded as a fertility preservation technique. However, it can be employed in certain clinical contexts.