Objective: Young breast cancer (BC) patients receiving chemotherapy are at risk of chemotherapy-induced menopause (CIM). We sought to define the incidence rate of premature menopause after chemotherapy and to retrospectively investigate factors related to the onset of menopause. Methods: We identified BC patients who had received chemotherapy at the Cancer Center (Centre Jean-Perrin). We selected premenopausal women aged between 18 and 50 years at the moment of diagnosis who received chemotherapy between 1994 and 2012. Results: Of the 345 selected patients, the median age was 42 years (interquartile range: 38-46). CIM was defined as amenorrhea for at least 2 years following the end of chemotherapy. A total of 260 premenopausal women versus 85 menopausal women were included. Among the 85 menopausal women, only 46 were in the CIM group (13.3%). This rate increased in the group of women aged >43 years at diagnosis and with early hot flushes. Conclusion: CIM occurred in 13.3% of BC patients after chemotherapy. Age >43 years and early hot flushes were significantly associated with the risk of CIM. We suggest that the definition of CIM should be standardized in the literature: "amenorrhea of at least 2 years" seems a good cutoff, although 2 patients recovered their menstrual cycles beyond this limit. (C) 2017 S. Karger AG, Basel