title: Rectal Lactobacillus species and their influence on the vaginal microflora: a model of male-to-female transsexual women.
abstract: BACKGROUND
  Based on Lactobacillus species co-colonizing the vagina and rectum, it has been hypothesized that the rectum may be an important reservoir for vaginal colonization by lactobacilli. There are no data on this issue in male-to-female transsexual women.
  
  
  OBJECTIVE
  We undertook this observational study to characterize the Lactobacillus species present in the neovagina and rectum of male-to-female transsexual women and to determine the degree of neovaginal-rectal co-colonization in order to gain a better understanding of the potential role of the gut as a reservoir for genital lactobacilli.
  
  
  METHODS
  Sixty-one male-to-female transsexual women with penile skin lined neovagina without clinical signs of infection were recruited on an ongoing basis from among male-to-female transsexual outpatients. Neovaginal and rectal smears were taken for molecular Lactobacillus species profiling by denaturing gradient gel electrophoresis (PCR-DGGE).
  
  
  METHODS
  Matching Lactobacillus species between neovagina and rectum.
  
  
  RESULTS
  Forty-three of the 61 male-to-female transsexual women (70.5%) simultaneously harbored the same lactobacilli in both the neovagina and rectum. We found 276 neovaginal and 258 rectal DGGE bands representing 11 Lactobacillus species, with 201 matches of the same Lactobacillus species in neovagina and rectum. 37 of the 61 women (61%) had two or more matching Lactobacillus species.
  
  
  CONCLUSIONS
  These data support the hypothesis that the rectum may play an important role as source of Lactobacillus species that colonies neovagina of male-to-female transsexual women. In view of the specific anatomical circumstances of the study population, these findings may be extended to the general population of women.
authors.affiliation: Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria.
authors.forename: Ljubomir
authors.initials: L
authors.lastname: Petricevic
authors.forename: Ulrike
authors.initials: U
authors.lastname: Kaufmann
authors.forename: Konrad J
authors.initials: KJ
authors.lastname: Domig
authors.forename: Manuel
authors.initials: M
authors.lastname: Kraler
authors.forename: Julian
authors.initials: J
authors.lastname: Marschalek
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kneifel
authors.forename: Herbert
authors.initials: H
authors.lastname: Kiss
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007778:Lactobacillus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D008297:Male; D064307:Microbiota; D008875:Middle Aged; D008954:Models, Biological; D012007:Rectum / Q000382:microbiology*; D063106:Transgender Persons / Q000706:statistics & numerical data; D014621:Vagina / Q000382:microbiology*
keywords: Gender Dysphoria; Lactobacillus; Neovagina; Rectum; Transsexual Women; Vaginal Lactobacilli