Objective: To compare the prevalence of contraception in breast cancer (BC) patients at risk of unintentional pregnancy (i.e. not currently pregnant or trying to get pregnant) and matched controls. Study design: The FEERIC study (Fertility, Pregnancy, Contraception after BC in France) is a prospective, multicenter case-control study, including localized BC patients aged 18–43 years, matched for age and parity to cancer-free volunteer controls in a 1:2 ratio. Data were collected through online questionnaires completed on the Seintinelles research platform. Results: In a population of 1278 women at risk of unintentional pregnancy, the prevalence of contraception at study inclusion did not differ significantly between cases (340/431, 78.9%) and controls (666/847, 78.6%, p = 0.97). Contrarily, the contraceptive methods used were significantly different, with a higher proportion of copper IUD use in BC survivors (59.5% versus 25.0% in controls p