Iris de Nie

134 C H A P T E R 9 This final chapter summarizes and discusses the findings of the work presented in this thesis. In addition, the strengths and limitations of this thesis will be discussed as well as the implications for clinical practice and future research.This thesis focused on andrological care in transgender women and aimed to obtain insight in topics such as the importance of fertility and family building, options for fertility preservation and the influence of GAHT on testicular and prostate tissue. SUMMARY OF MAIN FINDINGS In chapter 2 we discussed the results of a survey study we conducted among transgender people of reproductive age (±30 year) who initiated treatment for gender dysphoria during adolescence, before 2014, and as a consequence were posed with the inevitable choice of giving up the possibility of genetic parenthood for legal gender recognition. Almost all participants of our study underwent gonadectomy before the abolition of this law, and as a result became permanently infertile. We found that, for various reasons, none of the participants pursued fertility preservation prior to initiation of treatment, but a substantial percentage indicated that, in retrospect, they would have wanted to do so. Moreover, 1 out of 6 would have wanted to keep their gonads. The majority of the study population reported to currently have a desire for children, to desire children in the future, or to have children. Furthermore, many participants advised adolescents who are currently in the process of starting treatment, to pursue fertility preservation and hereby keep all options for future family building open. The preferred method for fertility preservation in trans women is cryopreservation of spermatozoa, obtained from a semen sample, prior to initiation of medical treatment. As described in chapter 3 , we found that at time of semen cryopreservation, semen quality in trans women is significantly decreased compared to WHO data on semen quality in the general population. Furthermore, the vast majority of semen samples were only suitable for invasive and expensive reproductive techniques (IVF/ICSI) to establish a pregnancy in the future. In order to find an explanation for the impaired semen quality in our study population, we assessed the influence of factors known to have a negative impact on semen quality in the general population, such as demographic factors and lifestyle.Although smoking and a higher age at time of fertility preservation were found to correlate with an impaired progressive motility, it was insufficient to explain the overall decreased semen quality in this cohort. Since it is often assumed that habitual behavior more typicallyobserved in trans women (e.g. tucking, wearing tight undergarments, and a low ejaculation frequency) is explanatory for the impaired semen quality, we decided to conduct a consecutive study with prospectively obtained data on these lifestyle factors. In chapter 4 , the results of this study are described. Semen quality was also impaired but no negative impact of age, BMI, smoking, alcohol consumption, cannabis use and medical history on the semen parameters was observed. However, when we assessed the influence of transgender specific lifestyle, it was found that approximately half of the study population reported to sometimes or always wear tight undergarments and that always wearing tight undergarments was associated with