title: [A case control study on the risk factors of male infertility].
abstract: OBJECTIVE
  To study the risk factors of male infertility.
  
  
  METHODS
  Case control study including 94 cases and control group with a ratio of 1 to 1.
  
  
  RESULTS
  The risk factors of male infertility were long time heavy smoking habit (OR = 3.45, 95% CI: 1.95 - 6.10), illegal sexual intercourse (OR = 7.29, 95% CI: 2.54 - 20.89), growing vegetable under plastic in higher temperature (OR = 6.73, 95% CI: 1.91 - 23.69), contact with benzene chemicals (OR = 20.53, 95% CI: 4.67 - 90.25) and having Ureaplasma urealyticum (Uu) infection (OR = 5.55, 95% CI: 2.28 - 13.53).
  
  
  CONCLUSIONS
  Male infertility was resulted from many factors repeatedly acting on men for long time. In order to prevent male infertility, issues as environmental pollution, occupational protection need to be improved while bad working condition and risky behavior should be changed.
authors.affiliation: Affiliated Qingzhou Hospital of Weifang Medical College, Weifang 262500, China.
authors.forename: Kai-gui
authors.initials: KG
authors.lastname: Qin
authors.forename: Yun-xia
authors.initials: YX
authors.lastname: Hou
authors.forename: Lan-ying
authors.initials: LY
authors.lastname: Zhang
authors.forename: Ming-hong
authors.initials: MH
authors.lastname: Li
authors.forename: Shu-xia
authors.initials: SX
authors.lastname: Yang
authors.forename: Yue
authors.initials: Y
authors.lastname: Ma
mesh_terms: D000328:Adult; D001554:Benzene / Q000633:toxicity*; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D004787:Environmental Pollution / Q000009:adverse effects*; D006801:Humans; D007248:Infertility, Male / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D016273:Occupational Exposure / Q000009:adverse effects; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D016869:Ureaplasma Infections / Q000150:complications; D016990:Ureaplasma urealyticum
chemical_list: D001554:Benzene