title: The relationship of Chlamydia trachomatis infection and male infertility.
abstract: OBJECTIVE
  Infertility affects at least 2 million couples in the United States. One third of infertility is attributed to male causes, but the etiology of most male infertility remains obscure. This study was designed to investigate the relationship between Chlamydia trachomatis and unexplained infertility in men.
  
  
  METHODS
  Questionnaires and serum were collected prospectively from 52 case subjects (men from couples with explicitly defined idiopathic infertility) and 79 control subjects (first-time expectant fathers).
  
  
  RESULTS
  Case subjects were significantly more likely than control subjects to be seropositive for antibody to C trachomatis at a titer of 1:64 or higher. By test of trend, higher titers were associated with higher odds ratios. Adjustment for age of either partner at initiation of pregnancy attempt, race, income, previous genitourinary symptoms or diagnoses, number of previous sexual partners, and barrier contraceptive use had no significant effect on the estimate of the odds ratio. One half of the men who were antibody positive had no history of genitourinary symptoms.
  
  
  CONCLUSIONS
  Our results suggest an association between infection with C trachomatis in men and unexplained infertility and imply that infection is frequently asymptomatic.
authors.affiliation: Division of General Internal Medicine and Health Services Research, University of California-Los Angeles School of Medicine.
authors.forename: G A
authors.initials: GA
authors.lastname: Greendale
authors.forename: S T
authors.initials: ST
authors.lastname: Haas
authors.forename: K
authors.initials: K
authors.lastname: Holbrook
authors.forename: B
authors.initials: B
authors.lastname: Walsh
authors.forename: J
authors.initials: J
authors.lastname: Schachter
authors.forename: R S
authors.initials: RS
authors.lastname: Phillips
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002690:Chlamydia Infections / Q000150:complications*; D002692:Chlamydia trachomatis; D005260:Female; D006801:Humans; D007248:Infertility, Male / Q000209:etiology*; D016015:Logistic Models; D008297:Male