ObjectiveOvarian failure is a common effect of treatment for cancer. The aim of this study was to describe the practices concerning ovarian protection and fertility preservation in young women treated for cancer. Study designWomen between 15 and 49 years old diagnosed with cancer between 2005 and 2014 were studied, abstracted from a representative French National Healthcare database. To assess practices concerning ovarian protection, gonadotropin-releasing hormone (GnRH) agonist consumption and ovarian transposition were analyzed. For fertility preservation, GnRH agonist consumption, ovarian cryopreservation and oocyte cryopreservation were analyzed. Explanatory variables were analyzed using a multilevel model. ResultsA total of 2447 women were identified. Among the 553 patients exposed to ovarian failure, 74 (13%) had ovarian protection (67 received GnRH agonists, 7 underwent ovarian transposition). Among the 227 women exposed to fertility alteration, 53 (23%) had fertility preservation (37 received GnRH agonists, 16 had ovarian or oocyte cryopreservation). Factors associated with ovarian protection were age under 40 years old (OR = 1.56 [1.5–1.62], p = 0.006) and diagnosis of breast cancer (OR = 1.15 [1.08–1.22], p < 0.001). The only factor associated with fertility preservation was breast cancer (OR = 1.17 [1.1–1.24], p < 0.001). The five-year probability of pregnancy was 3.8% and 9.8% (p = 0.26) for women with and without fertility preservation, respectively. ConclusionOver the last decade, ovarian protection and fertility preservation concerned 13% and 23%, respectively, of young French women treated for cancer. Awareness about ovarian protection and fertility preservation remain insufficient and need to be extended to improve this major aspect of cancer management.