Seminal fluid analysis (spermiogram) is the cornerstone of diagnostic procedure which evaluates male fertility. It determines whether the male partner of a couple is actually infertile, if the infertility level is sufficient to consider a procedure of assisted reproduction and eventually which assisted reproduction technique is the most appropriate. It is also the main guide for monitoring the effectiveness of the given therapy. It is therefore essential that it be carried out in a laboratory equipped with specific expertise and adequately trained personnel, which complies with international standards proposed by the World Health Organization (WHO), in the most recent version of 1999 and subsequent amendment of 2000. These standards include, among others, internal quality controls (inter- and intra-operator), to guarantee the reliability of results.
In an effort to increase standardization of semen examination, the main scientific societies of andrology, reproductive medicine, laboratory medicine and endocrinology recently developed methodological guidelines in a Workshop held in November 2003 in Rome and available in the literature. These guidelines, though essentially following the WHO indications, have made a number of improvements driven by the rapid numerical and qualitative increase of carrying out a test which progress in andrology is now proposing as “routine” (and less as an unpleasant test for a “problematic” situation).
Based on these assumptions, the main aspects of semen analysis are presented in as comprehensible a language as possible in order to give the reader simple and clear information about the test.
• Before collecting the sample for analysis, it is necessary to abstain from ejaculation for 2-7 days (WHO, 2000), traditionally 3-5 days, in order to standardize values.
• Collection, except in exceptional circumstances, must be carried out by masturbation at the laboratory, in a standard container (sterile for urine test); if collection is performed elsewhere, the sample must be delivered within 30-60 min of collection and protected from temperature fluctuations. Any loss of ejaculate fractions must be indicated.
• The sample is “macroscopically” evaluated in the laboratory to determine a series of physical-chemical and rheological characteristics, in particular, the volume, pH, appearance, fluidification and viscosity.
• Following microscopic evaluation to determine sperm concentration (concentration/ml , WHO reference value > 20 mil/ml; ejaculate concentration, WHO reference value > 40 mil/ejaculate) , motility (rapid and slow progressive motility > 50 % WHO reference value) and morphology sec . spermiocytogram (atypical forms <70 % WHO reference value)
• Further investigations are carried out concerning sperm vitality present in the ejaculate (sperm vitality > 70% WHO reference value), the concentration of leukocytes (<1 million/ml, WHO reference value), the presence of red blood cells (normally absent) of elements of the spermatogenetic germ line, exfoliation of the genitourinary tract epithelial cells, prostate corpuscles and areas of possible sperm agglutination.
The more sophisticated laboratories with specific andrology competences also use computerized analytical systems for seminal fluid evaluation (Computer Assisted Sperm Analysis – CASA). These systems, which require a substantial financial commitment, offer the considerable advantage of an extremely objective rilievo of semen parameters by a computer, without human influence. The advantage of such objectivity in the determination of seminal parameters is, however, limited by the lack of a precise standardization of the reference values. In other words, seminal investigations currently carried out by the computer must still be verified with manual operating standards and any computerized reports must always be accompanied by traditional ones.
Semen analysis (spermiogram) can be accompanied by the concomitant determination of other parameters, eg . the determination of antisperm antibodies, etc. Implementation of these tests depends on the specific laboratories .
Seminal analysis reports may include comments about the suitability of the sample collected, the number of sperm present, their motility and morphology (eg, oligospermia, asthenospermia, teratospermia) , but should never express clinical opinions about the patient’s fertility. Fertility indices proposed in the past which summarized patient fertility in a single datum (eg. Page-Houlding index) are at present considered to be meaningless, if not misleading. Data must be interpreted by the clinical andrologist (endocrinologist – andrologist) .
To conclude this brief description, the author would like to stress that seminal fluid analysis (semen analysis) is basically a laboratory investigation, ie a set of data that must be interpreted in the context of the clinical problem of the patient and correlated with any other investigations carried out by the patient within the specific diagnostic procedure .