title: People with gender dysphoria who self-prescribe cross-sex hormones: prevalence, sources, and side effects knowledge.
abstract: BACKGROUND
  There is a scarcity of research into the use of non-physician-sourced cross-sex hormones in the transgender population. However, when medication is not prescribed by health professionals, users' knowledge of such medication may be adversely affected.
  
  
  OBJECTIVE
  This study aims to define the prevalence of Internet-sourced sex hormone use in a population attending for initial assessment at a gender identity clinic, to compare the prevalence between gender-dysphoric men and women, and to compare knowledge of cross-sex hormone side effects between users who source cross-sex hormones from medical doctors and those who source them elsewhere.
  
  
  METHODS
  In the first part of the study, a cross-sectional design is used to measure the overall prevalence of sex hormone use among individuals referred to a gender clinic. The second part is a questionnaire survey aiming at measuring sex hormone knowledge among individuals referred to this clinic.
  
  
  METHODS
  Main outcome measures were (i) categorical data on the prevalence and source of cross-sex hormone use and (ii) knowledge of sex hormone side effects in a population referred to a gender clinic.
  
  
  RESULTS
  Cross-sex hormone use was present in 23% of gender clinic referrals, of whom 70% sourced the hormones via the Internet. Trans men using testosterone had a sex hormone usage prevalence of 6%; one-third of users sourced it from the Internet. Trans women had a sex hormone usage prevalence of 32%; approximately 70% of users sourced hormones from the Internet. Cross-sex hormone users who sourced their hormones from physicians were more aware of side effects than those who used other sources to access hormones.
  
  
  CONCLUSIONS
  One in four trans women self-prescribe cross-sex hormones before attending gender clinics, most commonly via the Internet. This practice is currently rare among trans men. Self-prescribing without medical advice leaves individuals without the knowledge required to minimize health risks.
authors.affiliation: Nottingham Gender Clinic, Mandala Centre, Nottingham, UK.
authors.forename: Nick
authors.initials: N
authors.lastname: Mepham
authors.forename: Walter P
authors.initials: WP
authors.lastname: Bouman
authors.forename: Jon
authors.initials: J
authors.lastname: Arcelus
authors.forename: Mark
authors.initials: M
authors.lastname: Hayter
authors.forename: Kevan R
authors.initials: KR
authors.lastname: Wylie
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D005783:Gender Identity; D012739:Gonadal Steroid Hormones / Q000600:supply & distribution* / Q000627:therapeutic use; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D020407:Internet / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D004366:Nonprescription Drugs / Q000600:supply & distribution* / Q000627:therapeutic use; D012651:Self Medication / Q000706:statistics & numerical data; D012737:Sex Factors; D011795:Surveys and Questionnaires; D013739:Testosterone / Q000600:supply & distribution / Q000627:therapeutic use; D014189:Transsexualism / Q000188:drug therapy*; D055815:Young Adult
chemical_list: D012739:Gonadal Steroid Hormones; D004366:Nonprescription Drugs; D013739:Testosterone
keywords: Cross-Sex Hormones; Gender Dysphoria; Internet; Prevalence; Transgender; Transsexualism