Study question What degree of reproductive health knowledge have oocyte donors? Summary answer The results of this study reveal that although oocyte donors are aware of the risks of possible fertility disorders, reproductive health knowledge is insufficient What is known already Sterility affects approximately 15% of the population of reproductive age, that is, young people. However, the information that young people have about fertility is scarce. Gamete donors are a group especially involved in reproductive issues since they help many people to solve their fertility problems and must undergo numerous tests before being accepted as such. However, there are no studies in Spain that deal with the knowledge that young people and, more specifically, donors, have about reproductive health and fertility Study design, size, duration A prospective, cross-sectional multicenter study including oocyte donors at ten fertility clinics performing gamete donation treatment in Spain. During a 2-month period (September-October 2020), 63 donors aged between 19 and 35 years old were recruited consecutively and a total of 63 oocyte donors were included as sample population. Most of them (78%) had not donated before Participants/materials, setting, methods 54% oocyte donors had secondary education and 43% have achieved university studies. Participants anonymously completed a questionnaire containing 41 questions divided into three sections: sociodemographic characteristics (11 items), knowledge on fertility and reproduction (22 items) and with a Likert scale, response to determine general reproductive health information as well as known risks for fertility disorders (8 items). Besides descriptive statistics, statistical analysis was performed with Chi square test. p < 0.05 was considered significant Main results and the role of chance In the survey 96.8% of the participants reported that they had already known the tests for fertility disorders. The increasing age of the women was correctly assessed by the participants of the study as a decisive risk factor for fertility, but it was found that exact knowledge was lacking: the decrease of a woman’s fertility by 39.7% was stated to occur on average at the age of 35–40 and by 30% at 40–45. Nevertheless, 66% of donors considered that fertility preservation should be carried out before the age of 35. 61.1% of the non-university donors reported that fertility can drop as a woman ages due to the decreasing number and quality of the remaining eggs. Among university donors, this percentage increases to 92,6% (p:0,034). Merely 47% of the participants informed what they understood that ovarian reserve is and 47.6% of donors believed that women create new eggs every month. Regarding the known risk factors for fertility, lifestyle was mentioned most frequently by all participants (91,2%), followed by chemo/radiotherapy (83,8%) and smoking, alcohol, and drugs (82,4%). Concerning the influence of the body mass index on fertility, differences were found between non-university (61%) and university donors (88,9%) (p:0,012). Limitations, reasons for caution Financial compensation has been found to be a motivating factor for oocyte donors and therefore one could question the representativeness of the participating oocyte donors. It would be of great interest to explore the significance of the financial compensation further. Wider implications of the findings: The present study reveals an existing requirement for information among oocyte donors, which is not only important for the success of prevention plans but also provides a foundation for possible strategies for the prevention of fertility disorder. Trial registration number Not applicable