EXTERNAL CAUSES [1] CONTACT WITH HARMFUL SUBSTANCES THAT POLLUTE THE ATMOSPHERE [2] TESTES HIGH TEMPERATURE [3] INFECTION [PROSTATITIS/EPIDIDYMITIS/GONORRHEA/C.TRACHOMATIS/TRICHOMONAS VAGINALIS/UREOPLASMA UREALITICUM] [4] INJURIES GENITAL ORGANS [5] DIET [6] OBESITY [7] SMOKING AND ALCOHOL [8] MOBILE PHONES AND OTHER RADIATION [INCREASES THE TEMPERATURE TESTICLE] [9] USE OF SUBSTANCES [ANABOLIC STEROIDS/DRUGW] [10] TIGHT UNDERWEAR [11] TIGHT TROUSERS