title: [Pro or contra Papanicolaou cytologic smear every 3 years].
abstract: OBJECTIVE
  To analyse the possibility of three-yearly screening for cervical cancer after two consecutive normal annual smears.
  
  
  METHODS
  Review of the literature.
  
  
  RESULTS
  In Switzerland 78% of women are screened spontaneously for cervical cancer. For 70% of this group the last smear was less than 18 months before. In other European countries or in North America programmed screening is every 3 or even 5 years. A lowered mortality rate is observed depending on the interval between screening. The benefit is only 2.7% between 3-yearly (90.8%) and yearly smears (93.5%). Finding an oncogenic HPV [16, 18, 31, 45] whilst investigating low grade cervical intraepithelial neoplasia (CIN1) is associated with a 17% risk of conversion into high grade cervical intraepithelial neoplasia (CIN3) within 3 years.
  
  
  CONCLUSIONS
  In Switzerland the conditions for screening on a 3-yearly basis are not fulfilled. We recommend an interval of only 2 years after 2 normal annual smears.
authors.affiliation: Département de Gynécologie-Obstétrique, CHUV, Lausanne.
authors.forename: J F
authors.initials: JF
authors.lastname: Delaloye
authors.forename: P
authors.initials: P
authors.lastname: De Grandi
mesh_terms: D005260:Female; D006801:Humans; D008403:Mass Screening / Q000706:statistics & numerical data*; D065006:Papanicolaou Test; D016019:Survival Analysis; D013557:Switzerland / Q000453:epidemiology; D013997:Time Factors; D002583:Uterine Cervical Neoplasms / Q000401:mortality / Q000517:prevention & control*; D014626:Vaginal Smears / Q000706:statistics & numerical data*
vernacular_title: Pour ou contre le frottis cytologique de Papanicolaou chaque trois ans.