Girls and younger women of fertile age are at risk of infertility and premature ovarian insufficiency, if they have received chemotherapy or radiotherapy. While many are offered fertility preservation before treatment, many are left with a need for follow-up after treatment, which is pointed out in this review. At the fertility clinic at Rigshospitalet, Denmark, a follow-up clinic has been introduced for previous cancer patients with focus on reproductive health, including assessment of ovarian function, planning of future pregnancies and initiation of hormone replacement therapy if needed.