Iris de Nie

8 C H A P T E R 1 GENERAL INTRODUCTION In this thesis, research is presented on the topic ‘Andrological care in transgender women’. Andrology is a medical discipline concerned with the anatomy, functions, and disorders of the male genital tract. Transgender women are people assigned male at birth, with a female gender identity. In this chapter we will first give some information about gender dysphoria and gender-affirming treatment for transgender women. Then, we will focus on the influence of gender-affirming treatment on the genital tract of transgender women and discuss the implications for fertility and cancer risk. For this purpose, we will also briefly explain the hypothalamic–pituitary–gonadal axis with particular focus on spermatogenesis and semen quality, and describe several types of cancers of the male genital tract and the role of sex steroids in the development of these malignancies. Lastly, we will describe the aims and content discussed in the different chapters. Gender dysphoria and gender-affirming treatment Gender dysphoria refers to the distress experienced by people with an incongruence between the sex assigned at birth and the experienced or identified gender. People assigned male at birth with a female gender identity are referred to as trans(gender) women, whereas birth-assigned males who identify as man are referred to as cis(gender) men. Transgender people may choose to start gender-affirming treatment to align physical characteristics with the identified gender, consisting of hormonal treatment and surgery. 1 For people presenting during adolescence, the first step of the medical treatment consists of puberty suppression with gonadotropin-releasing hormone agonists (GnRHa) in order to alleviate the distress caused by the development of secondary sex characteristics induced by puberty.When adolescents reach the age of 16 years, and have been on puberty suppressive therapy for at least six months, treatment is supplemented with gender- affirming hormones. Gender-affirming hormonal treatment (GAHT) for trans women involves androgen deprivation therapy on the one hand, and estrogen supplementation on the other hand. 2 The aim of this treatment is to lower serum testosterone to concentrations below 2 nmol/L and to elevate serum estradiol to concentrations between 200 to 600 pmol/L, in order to achieve feminization. Expected effects of this treatment include breast development, fat redistribution and a decrease in (facial) hair growth (Figure 1). 3 In addition, trans women of 18 years or older can opt for gender-affirming surgery (GAS) which can involve facial feminization, breast-augmentation, and bilateral orchiectomy often combined with vaginoplasty. 1 It has been shown that gender-affirming treatment effectively alleviates the experienced distress and increases quality of life, but even though it is generally considered safe, there may be risks and side effects, such as thromboembolic events or the development of sex hormone-related cancers (e.g. breast cancer). 4,5 Gender- affirming treatment also substantially affects the male genital tract but before that topic will be discussed, first some information on the hypothalamic–pituitary–gonadal axis, spermatogenesis and several types of cancers of the male genital tract will be given.