[Importance should be attached to the causes of azoospermia]

Azoospermia is determined when no spermatozoa can be detected on high-powered microscopic examination of a pellet after centrifugation of the seminal fluid. A physician can initially identify the causes of azoospermia by an exhausted history and a complete physical examination. Men with testicular or pretesticular azoospermia should be offered genetic testing and measurement of serum sex hormones to exclude genetic abnormalities or hypogonadism. And the CFTR mutation test should be recommended to exclude the possibility of CF present in the offspring when azoospermia is related to CBAVD or primary epididymal obstruction. Testicular size, inhibin B levels and serum FSH concentration help to evaluate spermatogenesis of the testis, and diagnostic testicular biopsy can further distinguish obstructive causes from testicular failure in case of normal-sized testes. Vasography may be used to identify the site of obstruction, but only when reconstructive surgery is performed.