190 Chapter 10 transgender adolescents who did not want to be referred for fertility preservation, say they are interested in adopting children (Brik et al., 2019). This difference raises the question if there might be a different view on adopting children in the United States and Canada compared with the Netherlands (Brik et al., 2019). Additionally, of interest in this regard, research on survivors of paediatric cancer show that the wish for future children may change over time, which is in line with the observation that some of the transgender adolescents we interviewed say that only during the period they got treatment with PS, they started to realise what the impact of some consequences could be (Armuand et al., 2014; Stein et al., 2014; Vrouenraets et al., 2022a). Furthermore, transgender adolescents, their parents, and clinicians stated that not being able to understand and appreciate the impact of certain consequences of treatment with PS, for example possible loss of fertility for one’s future life, is inherent to the adolescent’s developmental stage and/or age (Vrouenraets et al., 2022a). The WPATH Standards of Care (7th and 8th version) and Endocrine Society clinical practice guideline on care for transgender children and adolescents recommend counselling regarding fertility preservation options before initiating treatment with PS (Coleman et al., 2012; Coleman et al., 2022; Hembree et al., 2017). Our study shows that all 35 participating adolescents who were referred to start treatment with PS, had been informed about the risks of infertility, and 32 (91%) of them had been counselled about the option of fertility preservation (Brik et al., 2019). Counselling does not always lead to proceeding to actual fertility preservation however. Two studies from the United States indicate that transgender adolescents rarely use fertility preservation, respectively three and five percent (Nahata et al., 2017; Chen et al., 2017). Our study with transgirls in the Netherlands shows a much higher percentage (38%) of transgirls attempting fertility preservation, of which 75% was able to cryopreserve sperm (Brik et al., 2019). However, the same study shows that one-third of the transgirls who attempted fertility preservation, could not make use of it because they were not able to produce a semen sample because of early pubertal stage. This is in line with the results of other studies (de Sutter et al., 2002; Persky et al., 2020). Besides the physical limitations to producing a semen sample, several adolescents and their parents also mentioned barriers from a psychological perspective (Brik et al., 2019; Cheng et al., 2019; Vrouenraets et al., 2022a). Discomfort with reproductive anatomy, for example not feeling comfortable with masturbation or having an aversion of their penis, is a major influencing factor for some transgender adolescents in deciding about fertility preservation (Brik et al., 2019; Perksky et al., 2020; Nahata et al., 2017; Vrouenraets et al., 2022a). In sum, several aspects make it all the more important that transgender adolescents deciding on starting PS are adequately informed about the possible impact of GAMT on fertility, and about fertility preservation (Vrouenraets et al., 2022a). Guidance on best