188 Chapter 10 (Korte et al., 2008; Vrouenraets et al., 2015). Most people who participated in our 2015 study, the ones who criticize the use of early medical treatment and the ones who claim its benefits, agreed on the fact that the use of PS might change the way adolescents think about themselves (Vrouenraets et al., 2015). However, most of them thought that the use of PS did not inhibit the spontaneous development of a gender identity that would become congruent with the assigned gender after many years of having an incongruent gender identity. One research study shows that the period between 10 to 13 years of age, the time in which onset of puberty is common, may be a key period for retransition, and that gender identity may be more stable after these years for minors who have gender incongruent experiences before these ages (Steensma et al., 2011; Steensma et al., 2013). After these ages, gender identity changes in only a few. For instance, research shows that only 1.9% to 3.5% of the transgender minors who started GAMT during or after their puberty, discontinued their treatment and no longer desired GAMT (e.g. Brik et al., 2020; Carmichael et al., 2021; de Vries et al., 2011b; Hembree et al., 2017). Although numbers are low, these findings endorse that one’s gender identity can change in the period one is receiving treatment with PS. Some informants participating in our 2015 study stated that although PS may disrupt the development of a consistent gender identity, in some cases, the very real risks of the present (e.g. possible risk for suicide because of gender incongruent experiences) override the possible risks for the future (e.g. the individuals’ uncertainty) (Vrouenraets et al., 2015). This consideration is also mentioned in other studies (e.g. Turban & Keuroghlian, 2018). Furthermore, some adolescents who as young adults experienced a change in gender identity, and subsequently stopped GAMT, did not regret undergoing the treatment (Turban et al., 2018s; Turban & Keuroghlian, 2018; Turban, Loo, Almazan, & Keuroghlian, 2021). One young adult who stopped GAMT even stated that undergoing the treatment with GAH was essential for the consolidation of their gender identity (Turban et al., 2018a). Of current interest, in recent years the hypothesis of ‘rapid-onset gender dysphoria’ has been suggested (e.g. Littman, 2019; Hutchinson, Midgen, & Spiliadis, 2020). There is some controversy about what is described as rapid-onset gender dysphoria (Littman, 2019). Some describe rapid-onset gender dysphoria as the phenomenon where the development of gender dysphoria begins suddenly during puberty or after completion of puberty in adolescents or young adults who did not met criteria for gender dysphoria in childhood (Littman, 2019). Some wonder whether there are new aetiologies leading to gender dysphoria, whether rapid-onset gender dysphoria has the same desistence and persistence rates, and outcomes as the previously studied gender dysphorias, and whether it responses the same to treatment (Littman, 2019). A hypothesis on this rapidonset phenomenon is that the transgender identification and gender dysphoria of rapid-