Semen analysis is a fundamental part of male fertility investigation. Samples are produced by masturbation, ideally in a private room nearby to the andrology laboratory or submitted within one hour if produced off-site. The ejaculate should be collected in a wide-mouthed, clean, glass or plastic container, from a batch confirmed to be non-toxic to spermatozoa. Patients should be given clear instructions about collection of their sample. To ensure consistency and reliable interpretation of results, there should be a minimum of two days and maximum of seven days abstinence (1), and the complete sample should be collected. Loss of the first portion of the ejaculate, which mainly comprises sperm-rich prostatic fluid, may significantly affect sperm count and concentration.