Approximately 120,000 young women are diagnosed with cancer every year in the USA. Many will have treatment that can reduce their fertility, although few will learn this fact before their treatment commences. This presents a tremendous quality of life issue post-treatment, as evidenced in this Perspectives by a personal account from a 23-year-old woman diagnosed with breast cancer. Clinicians must increase awareness about patients' desires for motherhood and awareness about their individual reproductive potential. We demonstrate novel evidence about the wide variability in ovarian reserve in women of similar age, using assessment by antral follicle count. We show how a unified approach between oncology and fertility teams can help patients better understand their risk of treatment-related infertility, as well as how to take effective measures to mitigate it. Finally, we present options for fertility preservation, based on the time point at which consultation occurs.