title: The influence of sexual and social factors on the risk of Chlamydia trachomatis infections: a population-based serologic study.
abstract: BACKGROUND
  Genital chlamydia infections often are asymptomatic, which promotes their spread in the population. In women, the possible consequences of infection are pelvic inflammatory disease and infertility. Most studies on the prevalence of Chlamydia trachomatis have been based on clinical series, and prevalences tend to vary with the clinical setting. Few seroepidemiologic studies have emerged from industrialized countries.
  
  
  OBJECTIVE
  To assess the prevalence of Chlamydia trachomatis using culture and serology, and its relationship with possible risk factors.
  
  
  METHODS
  This was a population-based study involving completion of a self-administered questionnaire, analysis of cervical samples for Chlamydia trachomatis, and serologic tests for Chlamydia trachomatis antibodies.
  
  
  RESULTS
  The prevalence of Chlamydia trachomatis infection was 2.7%, and the seroprevalence was 24.7% among the sexually active women. Seropositivity was correlated with sexual behavior variables, and the incidence of serologic cross-reactivity with respiratory infections (strain TWAR) was low. Multivariate logistic regression analysis showed the number of sexual partners, age at first coitus, history of therapeutic abortion, and previous pelvic inflammatory disease to be independently correlated with seropositivity.
  
  
  CONCLUSIONS
  Early sexual experience and multiple lifetime sexual partners are independent risk factors for Chlamydia trachomatis infection.
authors.affiliation: Department of Family Medicine, University of Umeå, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Jonsson
authors.forename: R
authors.initials: R
authors.lastname: Karlsson
authors.forename: K
authors.initials: K
authors.lastname: Persson
authors.forename: P
authors.initials: P
authors.lastname: Juto
authors.forename: K
authors.initials: K
authors.lastname: Edlund
authors.forename: M
authors.initials: M
authors.lastname: Evander
authors.forename: A
authors.initials: A
authors.lastname: Gustavsson
authors.forename: E
authors.initials: E
authors.lastname: Bodén
authors.forename: E
authors.initials: E
authors.lastname: Rylander
authors.forename: G
authors.initials: G
authors.lastname: Wadell
mesh_terms: D000328:Adult; D002690:Chlamydia Infections / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D002692:Chlamydia trachomatis; D005260:Female; D006801:Humans; D016015:Logistic Models; D011159:Population Surveillance; D015995:Prevalence; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D012725:Sexual Behavior; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology; D014504:Urban Health