Bidet toilet use and incidence of hemorrhoids or urogenital infections: A one-year follow-up web survey

Teppei Kiuchi, Keiko Asakura, Makiko Nakano, Kazuyuki Omae

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4 Citations (Scopus)


Although bidet toilets are widely used in Japan, the relationship between habitual bidet toilet use and the incidence of hemorrhoids or urogenital infections has not been prospectively studied. We performed a web survey and followed bidet toilets users and non-users to assess the incidence of hemorrhoids or urogenital infections from 2013 to 2014. Study subjects were randomly selected from a research company's (Macromill, Inc.) web panel. The baseline survey inquired about toilet use and confounding parameters, and the follow-up survey examined outcome parameters. A total of 7637 subjects were analyzed using single or multiple logistic regression models. The prevalence odds ratios (ORs) between bidet toilet users and non-users for hemorrhoids, urological infections, and vulval pruritus were significantly > 1.0 but their incidence ORs were not significant. The adjusted incidence OR for bacterial vaginitis symptoms was significant (2.662, 95% confidence interval [CI] [1.315–5.520]). These findings suggest that positive relations between habitual bidet toilet use and hemorrhoids and urogenital symptoms, except bacterial vaginitis, were due to reverse causation. The incidence of bacterial vaginitis might be caused by bidet toilet use, but the incidence rates were too small to make a definite conclusion, and further studies are needed.

Original languageEnglish
Pages (from-to)121-125
Number of pages5
JournalPreventive Medicine Reports
Publication statusPublished - 2017 Jun 1



  • Bidet toilet
  • Female urogenital infection
  • Hemorrhoids

ASJC Scopus subject areas

  • Health Informatics
  • Public Health, Environmental and Occupational Health

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