Male factor infertility is solely responsible in ∼20% of cases and contributory in ∼30 - 40%. Therefore, in at least 50% of cases a male factor for infertility contributes to failure to conceive. A semen analysis is still a cornerstone laboratory evaluation and contributes to defining the severity of a possible single or contributing male factor to a couple's infertility.http://www.cmej.org.za/index.php/cme