Sertoli cell-only syndrome), the diagnostic value ... only syndrome or spermatogenic arrest (Bar-On ..... Parinaud, J. (eds), Human Sperm Acrosome Reaction.
Diagnostic tools in male infertility Christopher L.R.Barratt1 and Justin C.St John University Department of Obstetrics and Gynaecology, Birmingham Women's Hospital, Edgbaston, Birmingham B15 2TG, UK !
To whom correspondence should be addressed
Introduction The aim of this manuscript is to analyse critically several important areas in the diagnosis of male infertility, i.e. the role of basic semen assessment, sperm function testing and testicular biopsies. In addition, the incorporation of new diagnostic methods into the andrologist's repertoire is discussed, with particular reference to the role of molecular biology. Does a basic semen analysis have any diagnostic value? The clinical value of traditional semen parameters in the diagnosis of male fertility has recently been Human Reproduction Volume 13 Supplement 1 1998
the subject of considerable debate (Aitken et al., 1995; Barratt, 1995; Seibel and Zilberstein, 1995). Some authorities clearly hold the view that, apart from a diagnosis of azoospermia (or very severe oligozoospermia), a basic semen assessment is of little clinical value. This widely held belief, especially amongst practitioners in assisted reproductive technology (ART), does have some merit. For example, the diagnosis of a semen sample as 'abnormal' or 'normal' using the World Health Organization guidelines (WHO, 1987 and 1992) is artificial and has little diagnostic value. It is well documented that >75% of fertile men are diagnosed as abnormal if such criteria are used (Barratt et al, 1988; Barratt, 1995). Nevertheless, several comprehensive studies have examined the predictive value of traditional semen characteristics for in-vivo fertility and concluded that these parameters are predictive of pregnancy outcome (Mayaux et al, 1985; Bostofte et al, 1990; Barratt et al, 1992a, 1995). The availability of such data allows the estimation of the likelihood of subsequent conception for a new couple attending the clinic based on the semen parameters (see Bostofte et al, 1990). In addition to providing a diagnostic/predictive value for invivo conception, there is a plethora of studies documenting the assessment of traditional semen parameters that are clinically useful in the management of the couple requiring ART. For example, Campana et al. (1996) recently showed that below a cut-off value of 1X106 total motile spermatozoa present in the semen no pregnancies were achieved after intrauterine insemination (IUI). Burr et al. (1996) reported significantly lower pregnancy rates per cycle if the proportion of normal spermatozoa
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This review critically analyses the diagnostic value of conventional semen analysis and sperm function testing. It is clear from the data available that a high quality comprehensive semen assessment is a basic requirement in the diagnosis of the infertile couple. Sperm function testing has given disappointing results and a new generation of sperm function tests is required, which are cost effective, reliable and provide clinically significant information. In the future there will be an increasing use of molecular techniques to diagnose male infertility. Specific attention is given to the role of polymerase chain reaction in the diagnosis of genital infection and Y chromosomal and mitochondrial DNA deletions as examples. Key words: mitochondria/PGR/spermatozoa/Y chromosome/zona pellucida
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(ESHRE). At these courses, post-course examinations consistently show a considerable reduction in the variability of semen parameters (sperm concentration, motility and morphology) when compared with the pre-course examination. Therefore, rigorous training and use of appropriate quality control measures can lead to reliable semen assessments. The critical need to improve standardization in semen assessment is now widely accepted (e.g. see CECOS et al, 1997). Whilst traditional semen parameters are of significant clinical value, the data with regard to determination of antisperm antibodies, the detection of which is regarded as mandatory by WHO (1992), are more controversial. In-vivo studies show that low levels of antibody binding do not significantly effect conception (Barratt et al, 1992b; Ford et al, 1996; see also review by Collins et al, 1993). Recent IVF studies basically illustrate the same principle. In addition, difficulties with the repeatability of the assays (Clements etal, 1995; Matson, 1995) demonstrate that the detection of clinically significant amounts of antibodies require that spermatozoa are unable to penetrate human cervical mucus before a realistic diagnosis can be made (see Hendry et al, 1991). In order to make significant progress in this area, we need to understand more about how antibodies to spermatozoa are generated, and the nature of these antigens, which have a clear anti-fertility effect. We are a long way from either of these goals. Our understanding of the factors involved in the genesis of antisperm antibodies is poor (see Barratt and Cohen, 1986; Barratt et al, 1992b). Recent data suggest that the nature of antigen presentation, antigen load, and access to the immune system are all critical factors, at least for the development of tolerance (Ridge et al, 1996). Complementary experiments evaluating such factors in the genesis of antisperm antibodies are now required, e.g. the use of phage display to identify clinically significant antigens. The time has come to incorporate current immunological techniques into reproductive biology. In conclusion, provided appropriate quality control and quality assurance programmes are in operation, traditional semen parameters are of clinically significant value in the diagnosis of male infertility. A comprehensive high quality semen
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in the semen was
