title: Incidence of thrombophilia and venous thrombosis in transsexuals under cross-sex hormone therapy.
abstract: OBJECTIVE
  To evaluate the incidence of venous thromboembolism (VTE) in transsexual patients and the value of screening for thrombophilia in this population.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Academic research institution.
  
  
  METHODS
  Two hundred fifty-one transsexuals (162 male-to-female [MtF] and 89 female-to-male [FtM] transsexuals).
  
  
  METHODS
  Screening for activated protein C (aPC) resistance, antithrombin III, free protein S antigen, and protein C deficiency.
  
  
  METHODS
  Incidence of thrombophilic defects and VTE during cross-sex hormone therapy.
  
  
  RESULTS
  Activated protein C resistance was detected in 18/251 patients (7.2%), and protein C deficiency was detected in one patient (0.4%). None of the patients developed VTE under cross-sex hormone therapy during a mean of 64.2 +/- 38.0 months. There was no difference in the incidence of thrombophilia comparing MtF and FtM transsexuals (8.0% [13/162] vs. 5.6% [5/89], respectively).
  
  
  CONCLUSIONS
  VTE during cross-sex hormone therapy is rare. General screening for thrombophilic defects in transsexual patients is not recommended. Cross-sex hormone therapy is feasible in MtF as well as in FtM patients with aPC resistance.
authors.affiliation: Department of Gynaecologic Endocrinology and Reproductive Medicine, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria. johannes.ott@meduniwien.ac.at
authors.forename: Johannes
authors.initials: J
authors.lastname: Ott
authors.forename: Ulrike
authors.initials: U
authors.lastname: Kaufmann
authors.forename: Eva-Katrin
authors.initials: EK
authors.lastname: Bentz
authors.forename: Johannes C
authors.initials: JC
authors.lastname: Huber
authors.forename: Clemens B
authors.initials: CB
authors.lastname: Tempfer
mesh_terms: D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D020249:Hormone Replacement Therapy / Q000009:adverse effects; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D019851:Thrombophilia / Q000097:blood / Q000139:chemically induced / Q000453:epidemiology*; D014189:Transsexualism / Q000097:blood / Q000188:drug therapy / Q000453:epidemiology*; D020246:Venous Thrombosis / Q000097:blood / Q000139:chemically induced / Q000453:epidemiology*; D055815:Young Adult