Interpreting Semen Analysis and Level 2 Sperm Testing

Semen analysis is the first test requested when fertility potential of a man becomes questionable. The results of the semen analysis are often taken as a surrogate measure of his ability to father a pregnancy. The test provides information on the functional status of the seminiferous tubules, epididymis, seminal vesicles, and the prostate. Thus the results of the test should be interpreted in the light of a full clinical history and physical examination of the patient to determine possible causes for reduced fertility potential and of any suboptimal semen analysis result (see Chap. 1). Although semen analysis is the most practical laboratory assessment of the male we have, it comes with many limitations. The foremost of these limitations is the limited reliability of the result of semen analysis due to variations in the method and timing of obtaining ejaculates and the lack of standardization of the semen analysis methodology [1–4]. There is also limitation of scope as semen analysis is concerned primarily with measuring the volume of the ejaculate and with assessing the number, motility, and the shape of the sperm population. The count of other cellular contents such as spermatids and leucocytes may be noted. The narrow scope of the analysis reduces its ability to identify an underlying pathology when the analysis results are substandard. This in turn contributes to the relatively low prognostic power of semen analysis as a diagnostic test. When azoospermia cases are excluded, the results of semen analyses do not always correlate with pregnancy rates or infertility [5, 6]. Nevertheless, semen analysis provides essential information on the clinical status of the man being investigated.