There are many reasons why men become sterile. It can be due to alcoholism, stress, obesity and hormonal problems.

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  1. What Causes Men to be Sterile? – http://answers.ask.com/Health/Reproductive/what_causes_men_to_be_sterile
  2. What causes infertility and sterility? – http://wiki.answers.com/Q/What_causes_infertility_and_sterility
  3. What causes sterility? – http://wiki.answers.com/Q/What_causes_sterility
  4. What are the causes of sterility.? – http://wiki.answers.com/Q/What+would+cause+a+man+be+sterile
  5. What is a disease that can cause sterility? – http://wiki.answers.com/Q/What_is_a_disease_that_can_cause_sterility
  6. Why would a vasectomy cause sterility? – http://wiki.answers.com/Q/Why_would_a_vasectomy_cause_sterility
  7. Why does a vasectomy cause sterility? – http://wiki.answers.com/Q/Why_does_a_vasectomy_cause_sterility
  8. What can cause sterility in men? – http://wiki.answers.com/Q/What_can_cause_sterility_in_men