1.1.1.4 Idiopathic

In 30–40% of male infertility cases, the cause is classified as idiopathic [13]. In these cases, despite attempting to identify potential mechanisms at play, a cause for abnormal sperm number, morphology, or function cannot be identified [13]. Idiopathic causes should be distinguished from unknown causes which is where men with normal semen analysis and no other identified cause for infertility are unable to impregnate an apparently clinically normal female partner.
