The issue of improving the living conditions of breast cancer survivors is receiving increasing attention. The main aspects concerned are sexuality, fertility and reintegration problems, particularly among young women. The integration of patients’ needs into their care, as well as the experience of their fertility and sexuality, is an important aspect today. However, to our knowledge, no studies including a qualitative component have been carried out in France in the exploration of the needs considered priority and the living conditions of young women in the post-cancer. This cross-sectional mixed population study (quantitative and qualitative components) will involve several registers involved in the epidemiological surveillance of cancers via the FRANCIM Network, Public Health France and INCA (National Cancer Institute). Its main objective is to identify the clinical and socio-economic determinants of fertility and sexuality of young women after a CS. The quality of life, psychological characteristics (anxiety/depression) and socio-professional reintegration of young women after a CS will also be studied. The qualitative component of the study will explore the experiences of young patients after a CS and the aspects considered priority by the patients in improving their management and conditions after the disease.