Is quality assurance in semen analysis still really necessary? A clinician's viewpoint

Application of sperm motion kinematics and motility-related proteins for prediction of male fertility

The selection of superior sires is paramount for enhancing the efficiency of animal production in the livestock industry. However, semen quality assessment still relies on conventional semen analysis techniques in both animals and humans. Despite extensive efforts to develop various biomarkers for more accurate and precise predictions of male fertility potential, more effective physiological indicators and advance potential biomarkers are needed. Herein, we aimed to develop new potential biomarkers related to sperm motion kinematics for male fertility prediction. We first evaluated sperm motion kinematic parameters and expression levels of sperm motility-related proteins of 30 Duroc boars. We then explored the correlation between litter size, sperm motion kinematics parameters, and sperm motility-related proteins. Progressive sperm motility (%), rapid sperm motility (%), slow sperm motility (%), straight-line velocity (μm/s), linearity (%), beat cross frequency (Hz), mean angular displacement (degree), wobble (%) were correlated with litter size. Furthermore, the expression of axonemal dynein light intermediate polypeptide 1 (DNALI1) and radial spoke head protein 9 homolog (RSPH9) correlated with litter size. The overall accuracy exceeded 60% for predicting litter size using these sperm motion parameters and proteins. Notably, our study observed an increase in litter size after predicting litter size using these parameters and proteins. Thus, sperm motion kinematic parameters and protein expression, particularly of DNALI1 and RSPH9, could serve as new biomarkers for male fertility. These results may contribute to improved understanding of the mechanisms underlying sperm motility.

Interobserver Variability in Semen Analysis: Findings From a Quality Control Initiative

Introduction For laboratory tests, precision and accuracy are indispensable to ensure reliable results for both clinical diagnosis and research endeavors. The accuracy and reliability of results are important because they have an impact on both patient management and research. In this study, we evaluated the inter-observer variability between a trained technician and two academic residents, which acted both as a quality control measure as well as an assessment of training outcomes. Material and methods Freshly obtained semen samples from 28 subjects coming to the andrology laboratory were used. Semen analysis was performed by a regular technician permanently posted in the laboratory and two residents on completion of their posting in the andrology laboratory. All three examined the same sample after liquefaction for assessment of sperm motility, sperm concentration, sperm vitality, and sperm morphology. Semen analysis was done as per the recommendations of the WHO. Results The results of the study are presented as a coefficient of variation (CV), S charts, and Bland-Altman plot where we evaluated the interobserver variability in parameters on semen analysis of the same sample by three different assessors. The mean CV for sperm concentration across the samples was 6.24%. For sperm vitality, sperm morphology, and sperm motility the mean CV was 10.14%, 2.66%, and 8.11%, respectively. The S chart and Bland-Altman plot found a few random errors in measurements. Conclusion Regular quality control assessments are essential and should be implemented in andrology laboratories to ensure accurate and reliable results. Proper training of laboratory personnel is also vital for consistent outcomes. Other measures such as equipment calibration, use of high-quality reagents, and standard reporting are also crucial for the best results from a laboratory.

Ejaculatory abstinence in semen analysis: does it make any sense?

Background

The precise effect of ejaculatory abstinence on semen parameters is highly debatable, especially among subfertile men. Previous studies on effect of abstinence time on different semen parameters have reported controversial results. The aim of this study was to retrospectively assess the variance of semen parameters with different periods of ejaculatory abstinence among both a population of normozoospermic (n = 1621) and oligozoospermic (n = 416) Tamil men, presenting to a fertility clinic for an infertility evaluation (N = 2037).

Materials and Methods

A retrospective analysis of 2037 semen analysis reports involved grouping patients based on their ejaculatory abstinence, that is, <24 h, 1 to 2 days, 3 to 7 days, 8 to 15 days, 16 to 30 days, and >30 days. All semen parameters were assessed as per the World Health Organization (WHO, 2010) recommended guidelines. The unpaired two-tailed t-test and Welch's analysis of variance (ANOVA) combined with Games-Howell post hoc test were used for statistical analysis. A p value <0.05 was considered to be statistically significant.

Result

A retrospective analysis of data (N = 2037) identified no statistically significant differences in semen parameters of sperm concentration, percentage of progressively motile sperm, and normal sperm morphology in both normozoospermic and oligozoospermic individuals across different groups of abstinence. Semen volume was the only parameter that showed a statistically significant difference in both groups (p < 0.0001). In both normozoospermic and oligozoospermic men, the group with <24 h abstinence had the highest mean percentage of progressively motile sperm and normal sperm morphology.

Conclusion

The findings of this study suggest that ejaculatory abstinence may be highly arbitrary, and the recommendation of a strict 2- to 7-day abstinence per the WHO may be liberalized. In both normozoospermic and oligozoospermic men, semen parameters associated with an abstinence of <24 h were found to be noninferior as compared to longer ejaculatory abstinence intervals. These findings support in eliminating conservative recommendations as far as abstinence is concerned and suggest that patients may be asked to collect a semen sample on the day they present for an infertility evaluation, regardless of abstinence.

The 1999 and 2010 WHO reference values for human semen analysis to predict sperm DNA damage: A comparative study

Standard semen parameters are often used to predict male fertility, but whether the 2010 World Health Organization (WHO 2010) thresholds are better predictors than the 1999 thresholds has not been investigated. In this study, we addressed this issue using sperm DNA fragmentation (SDF) as a marker of male fertility in 134 subfertile male individuals. To compare the predictive value of the 1999 thresholds with the 2010 cutoffs, the Youden indices (YIs) of all possible thresholds were calculated using receiver operating characteristic (ROC) curves and compared to each other and to the respective YIs of optimal thresholds. We found that the area under the ROC curves of progressive motility and vitality was the highest among standard semen parameters, and that the YI of both parameters from the 2010 manual was comparable to the respective optimal YIs. In contrast, the threshold of sperm concentration and total sperm number from both WHO recommendations demonstrated low YIs, with substantial differences to the respective optimal YIs. The YIs of normal morphology cutoffs from both WHO manuals were slightly different from each other and from the respective optimal YIs. In conclusion, the 2010 thresholds for progressive motility and vitality are superior to the 1999 thresholds in predicting SDF, whereas the cutoff value of sperm concentration, total sperm number and normal morphology may need further revisions to increase their accuracy.

High glucose concentrations per se do not adversely affect human sperm function in vitro

Diabetes mellitus (DM) represents one of the greatest concerns to global health and it is associated with diverse clinical complications, including reproductive dysfunction. Given the multifactorial nature of DM, the mechanisms that underlie reproductive dysfunction remain unclear. Considering that hyperglycemia has been described as a major effector of the disease pathophysiology, we used anin vitroapproach to address the isolated effect of high glucose conditions on human sperm function, thus avoiding otherin vivoconfounding players. We performed a complete and integrated analysis by measuring a variety of important indicators of spermatozoa functionality (such as motility, viability, capacitation status, acrosomal integrity, mitochondrial superoxide production and membrane potential) in human sperm samples after incubation withd- andl-glucose (5, 25, or 50 mM) for 24 and 48 h. No direct effects promoted by 25 or 50 mMd-glucose were found for any of the parameters assessed (P>0.05), except for the acrosome reaction, which was potentiated after 48 h of exposure to 50 mMd-glucose (P<0.05). Interestingly, non-metabolizablel-glucose drastically increased superoxide production (P<0.05) and suppressed sperm motility (P<0.05) and capacitation (P<0.05) after 24 h of treatment, whereas mitochondrial membrane potential (P<0.05), acrosomal integrity (P<0.01) and viability (P<0.05) were later decreased. The overall results suggest that high glucose levelsper sedo not influence human sperm functionin vitro, which stresses the importance of other factors involved in DM pathology. Nevertheless, the absence of metabolizable glucose contributes to a severe impairment of sperm function and thus compromises male fertility.

Free Portuguese abstract: A Portuguese translation of this abstract is freely available athttp://www.reproduction-online.org/content/150/1/77/suppl/DC1.

A translational medicine appraisal of specialized andrology testing in unexplained male infertility

The diagnostic and prognostic validity of sperm function biomarkers is particularly relevant for males with unexplained infertility in which routine semen analysis fails to detect subcellular sperm dysfunctions. In this general review, we examine the role and significance of specialized andrology laboratory tests from past to present and provide a glance toward the future. We concluded that the assessment of sperm DNA damage and oxidative stress provide a relatively independent measure of fertility that yields diagnostic and prognostic information complementary to, but distinct and more significant than, standard sperm parameters. Since none of the available methods for such testing have been fully translated, further research is necessary to evaluate their cost-effectiveness when applied in large scale to daily medical practice. Application of translational medicine concepts would also be useful to accelerate the clinical application of recent discoveries in the fields of genomics, proteomics and metabolomics.

Relationship between Sperm Hyaluronan-Binding Assay (HBA) Scores on Embryo Development, Fertilisation, and Pregnancy Rate in Patients Undergoing Intra-Cytoplasmic Sperm Injection (ICSI)

Introduction:

The novel development of the sperm hyaluronan-binding assay (HBA) has now been routinely used in some laboratories worldwide to predict sperm maturity and functionality. Hence, the purpose of this study is to evaluate if embryo development, quality, fertilisation and pregnancy rates are affected by low HBA values.

Methods:

A total of192 female patients who underwent intra-cytoplasmic sperm injection (ICSI) were compared retrospectively in terms of embryo development, fertilisation, and pregnancy rates with their husbands' HBA score. Patients' husbands were required to undergo a HBA test before the start of their stimulation cycle to determine if their semen was suitable to undergo ICSI or in-vitro fertilisation (IVF). P-value < 0.05 was considered significant.

Results:

Patients were divided into four groups, group A (HBA ≤ 15%), group B (HBA > 15% < 35%), group C (HBA ≥ 35% < 60%), and group D (HBA ≥ 60%). The fertilisation rate for groups A, B, C, and D were 67.9%, 73.1%, 72.5%, and 77.1% respectively. Group D had a fertilisation rate significantly higher than the rest of the groups ( p = 0.016). The pregnancy rate for group D was also significantly higher amongst the four groups ( p = 0.041), whereas the pregnancy rate for groups B and C was similar (42.4% versus 41.1% respectively). Day three cleavage rate (the ability to reach six cells and beyond) was highest for group D compared to the other groups ( p = 0.002).

Conclusion:

The higher the HBA score, the better the fertilisation, pregnancy, and cleavage rates. This shows that HBA does have the ability to select mature sperms with normal chromosome development and oocyte-binding capability.

Molecular mechanisms beyond glucose transport in diabetes-related male infertility

Diabetes mellitus (DM) is one of the greatest public health threats in modern societies. Although during a few years it was suggested that DM had no significant effect in male reproductive function, this view has been challenged in recent years. The increasing incidence of DM worldwide will inevitably result in a higher prevalence of this pathology in men of reproductive age and subfertility or infertility associated with DM is expected to dramatically rise in upcoming years. From a clinical perspective, the evaluation of semen parameters, as well as spermatozoa deoxyribonucleic acid (DNA) integrity, are often studied due to their direct implications in natural and assisted conception. Nevertheless, recent studies based on the molecular mechanisms beyond glucose transport in testicular cells provide new insights in DM-induced alterations in male reproductive health. Testicular cells have their own glucose sensing machinery that react to hormonal fluctuations and have several mechanisms to counteract hyper- and hypoglycemic events. Moreover, the metabolic cooperation between testicular cells is crucial for normal spermatogenesis. Sertoli cells (SCs), which are the main components of blood-testis barrier, are not only responsible for the physical support of germ cells but also for lactate production that is then metabolized by the developing germ cells. Any alteration in this tied metabolic cooperation may have a dramatic consequence in male fertility potential. Therefore, we present an overview of the clinical significance of DM in the male reproductive health with emphasis on the molecular mechanisms beyond glucose fluctuation and transport in testicular cells.

Ten years' experience with an external quality control program for semen analysis

OBJECTIVE

To gauge the performance of laboratories and impact of the German semen analysis external quality control program (QuaDeGA) over its first 10 years.

DESIGN

Retrospective analysis of QuaDeGA's twice yearly distribution of fixed semen samples and electronic material documenting sperm motility. Ranking of each participant's responses was determined according to their relation to a "target window."

SETTING

Multicenter. PAITENT(S): Healthy donors.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Laboratory performance, World Health Organization (WHO) adherence.

RESULT(S)

Over 19 runs, there was a steady increase of participants (280 laboratories), the largest group being private urologic practices. Although use of WHO-recommended Neubauer chamber (from 33% to 55%) and diluent (from 11% to 32%) increased, the opposite occurred with morphology staining protocols (from 41% to 19%). Overall, <8% of laboratories truly followed WHO guidelines. Median-based comparisons, replacing reference laboratories, resulted in a merging of performance rankings regardless of the protocols used.

CONCLUSION(S)

Adherence to WHO recommendations is low, with the majority of laboratories using methods expressly opposed by the guidelines. Participation in QuaDeGA was found to improve the performance of the laboratories involved in the program. However, the use of median-based ranking, while decreasing the extent of variance between laboratories, brings into question the significance of the rankings.

Tales of healthy men: male reproductive bodies in biomedicine from 'Lebensborn' to sperm banks

Using the example of 'sperm tales', borne out of the biomedical technologies that went hand in hand with the establishment of the 'science of man' (andrology), the article engages with the epistemic evolution of interrelated biomedical theories and concepts of what constitutes a 'healthy' reproductive male body. The article asks: how has the normative ideal male body been either perpetuated or interrogated through these tales of male reproduction at the interface between scientific and medical technologies? And how were changes to the normalization of male bodies central to clinical practices and cultural understandings of health and illness? With many aspects of the medical history of male reproduction in the 20th century still unexplored, this article will focus on the growing intervention of biomedicine to 'treat' male infertility by way of the classification, standardization and normalization of male corporeality, focusing in particular on the representation and construction of men and the male body, as reflected in medical science and practice from the second half of the 20th century onwards in Germany. The article analyses the rise in importance of sperm in biomedical investigation, including a consideration of the construction of infertility as the defining force behind concepts of 'healthy men', and examines the related conceptualization of male reproductive bodies at the crossroad between 'healthy' and 'normal'. It is argued that the ideal of male reproduction as being inherently healthy has lost ground. By the late 20th century, male bodies have become vulnerable, at least as represented in medical science and technology.

Semen analysis and sperm function testing

Despite controversy regarding the clinical value of semen analysis, male fertility investigation still relies on a standardized analysis of the semen parameters. This is especially true for infertility clinics in both developing and developed countries. Other optional tests or sophisticated technologies have not been widely applied. The current review addresses important changes in the analysis of semen as described in the new World Health Organization (WHO) manual for semen analysis. The most important change in the manual is the use of evidence-based publications as references to determine cutoff values for normality. Apart from the above mentioned changes, the initial evaluation and handling methods remain, in most instances, the same as in previous editions. Furthermore, the review evaluates the importance of quality control in andrology with emphasis on the evaluation of sperm morphology. WHO sperm morphology training programmes for Sub-Saharan countries were initiated at Tygerberg Hospital in 1995. The external quality control programme has ensured that the majority of participants have maintained their morphological reading skills acquired during initial training. This review reports on current sperm functional tests, such as the induced acrosome reaction, and sperm-zona pellucida binding assays, as well as the impact of sperm quality in terms of DNA integrity, and the relationship of sperm function tests to sperm morphology.

Increased receptor for advanced glycation end products in spermatozoa of diabetic men and its association with sperm nuclear DNA fragmentation

Although the majority of patients with diabetes have disorders in sexual function, associations between diabetes mellitus and sperm function at the molecular level are largely unknown. As receptor for advanced glycation end products plays a key role in many diabetic complications, we hypothesised that it may be involved in sperm nuclear DNA fragmentation. RAGE levels were determined using ELISA and western blot analysis in sperm samples from 32 diabetic and 35 nondiabetic men. Sperm DNA fragmentation was assessed using TUNEL assay. Diabetic men had significantly higher mean levels of RAGE protein (P < 0.001) and DNA fragmentation (P < 0.001) in spermatozoa. Sperm RAGE was directly correlated to sperm DNA fragmentation in diabetic men (r = 0.81, P < 0.001). The high positive correlation between RAGE levels and nuclear DNA fragmentation in spermatozoa of diabetic men suggests a central role of RAGE in disturbances in sexual function of diabetic men.

Semen analysis: a new manual and its application to the understanding of semen and its pathology

This article reviews the latest edition of the World Health Organization's manual on semen analysis, a comprehensive instructional guide. The methodology used in the assessment of the usual variables in semen analysis is described, as are many of the less common, but very valuable, sperm function tests. Seminal fluid preparation techniques for procedures such as in vitro fertilization and intrauterine insemination are also outlined in the manual. In addition, it details many useful techniques for the assessment of seminal fluid. It will be a very useful manual for any laboratory that carries out analyses of seminal fluid.

Practical semen analysis: from A to Z

Accurate semen analysis is critical for decisions about patient care, as well as for studies addressing overall changes in semen quality, contraceptive efficacy and effects of toxicant exposure. The standardization of semen analysis is very difficult for many reasons, including the use of subjective techniques with no standards for comparison, poor technician training, problems with proficiency testing and a reluctance to change techniques. The World Health Organization (WHO) Semen handbook (2010) offers a vastly improved set of standardized procedures, all at a level of detail that will preclude most misinterpretations. However, there is a limit to what can be learned from words and pictures alone. A WHO-produced DVD that offers complete demonstrations of each technique along with quality assurance standards for motility, morphology and concentration assessments would enhance the effectiveness of the manual. However, neither the manual nor a DVD will help unless there is general acknowledgement of the critical need to standardize techniques and rigorously pursue quality control to ensure that laboratories actually perform techniques 'according to WHO' instead of merely reporting that they have done so. Unless improvements are made, patient results will continue to be compromised and comparison between studies and laboratories will have limited merit.

Quality Management Issues in the Assisted Reproduction Laboratory

In the United States, the Clinical Laboratory Improvement Act (CLIA) of 1988 describes requirements and guidelines for implementing a quality control/quality assurance (QC/QA) program for moderate and high complexity laboratories. These requirements and guidelines apply to Assisted Reproductive Technology (ART) laboratories as well. The general topic of QC and QA as it pertains to in vitro fertilization (IVF) and embryo transfer (ET) is extensively reviewed. This review summarizes many of the QC and QA events that contribute to the advancement of knowledge in this biotechnological field. These events include control of the culture environment inside and outside of the incubator, as well as factors that affect culture media. This review also discusses, in considerable detail, the QC and the QA that pertain to equipment used within the laboratory and how to control for potential contaminants, which reside within the laboratory. This review provides evidence to indicate the need for laboratory personnel to monitor quality improvement issues on a continuous basis. Personnel must be willing to change as improvements in technology occur in order to meet the ever-evolving demands of a more difficult patient population. Suggestions for meeting these demands are offered.

Quality assurance and quality control in the laboratory andrology

Quality assurance (QA) and quality control (QC) are fundamental aspects of any laboratory measurement. However, in comparison with other medical disciplines, the need for QA and QC in laboratory andrology has been recognized only recently. Furthermore, there is evidence that the effort required to undertake QA and QC has not been wholly welcomed by some clinicians. Nevertheless, accrediting bodies and regulatory authorities increasingly require evidence that laboratories have effective QA and QC measures in place because both are central to the quality management processes. Following the publication of the 5th edition of the World Health Organization Laboratory Manual, existing QA and QC systems will need to be updated to take into account some of the methodological changes recommended by the manual. Three of these are discussed in this commentary; they relate to: (i) the move to infer semen volume from its weight; (ii) the re-classification of sperm motility grades from four to three; and (iii) the publication of a lower reference limit for morphology of 4% (with a corresponding 95% confidence interval of 3%-4%). The importance of QA and QC in all laboratory tests, including up and coming new tests to assess sperm DNA integrity, is discussed. The need for adequate initial training and continuing professional development programmes to support laboratory scientists performing andrology is also described.

Quality specifications for seminal parameters based on clinicians' opinions

BACKGROUND

The aim of this study was to identify analytical quality specifications for seminal parameters based on clinicians' opinions, and to compare with those based on biological variability and state of the art.

MATERIAL AND METHODS

Two questionnaires with case histories were sent to laboratories participating in the Spanish programme of external quality on semen analysis for distribution to as many specialist clinicians as possible. Our intention was to determine the critical difference (CD), defined as the difference needed between two consecutive results obtained from semen analysis to be 95 % confident that the two results actually are different. Subsequently, we calculated the specifications of analytical quality in accordance with the clinicians' opinions.

RESULTS

The CDs obtained from the median value of the differences between the initial value and that given in the clinicians' replies were similar in clinical situations of improvement or worsening in the infertile normozoospermic male, and also in worsening situations for male patients presenting a significant alteration in seminal parameters. For improvement in this latter case, the CD cited as necessary in the clinicians' opinion was much higher than that for the other clinical situations. At a desirable level of quality, for concentration and total motility the coefficients of variation in the clinicians' opinion were below those based on biological variability and the state of the art. However, for type "a+b" motility, type "a" motility, morphology and vitality the coefficients of variation based on the clinicians' opinions were higher than those based on biological variability and lower than those based on the state of the art.

CONCLUSIONS

Quality specifications for seminal parameters based on clinicians' opinions depend to a large extent on the clinical situation and on the seminal parameter being analysed.

Cystic dilatation of the rete testis: a hidden diagnosis among infertile men

Cystic dilatation of the rete testis, often also known as cystic ectasia of the rete testis, is a poorly understood condition that may be a cause of male infertility. This study examined the frequency of this condition in 749 men attending an infertility clinic with their partners. Of these 749 men, semen analysis was abnormal in 275 (37%) but apparently normal in 474 (63%). All the men attending the infertility clinic underwent a testicular ultrasound. Of these 749 men, the lesion was present in nine (1.2%); it was present bilaterally in three and unilaterally in six. In two men, one of whom had a bilateral lesion, the sperm count was normal. It is unclear whether this lesion is a cause of infertility but it is important that this condition is diagnosed so that its prevalence and its relationship to infertility can be ascertained.

Is sperm evaluation useful in predicting human fertility?

Traditionally, the diagnosis of male infertility has relied upon microscopic assessment and biochemical assays to determine human semen quality. The conventional parameters given most importance have been the concentration, motility, and morphology of sperm in the ejaculate. Most laboratories also include ‘sperm suitability’ tests where the subpopulations of sperm more likely to finish the marathon journey to the oocyte are separated by density centrifugation. These tests are essential to provide the fundamental information on which clinicians base their initial diagnosis. However, none of these parameters addresses sperm function and their clinical value in predicting fertility is questionable. The advent of intracytoplasmic sperm injection (ICSI) has further reduced the significance and perceived need for sperm quality tests since ICSI requires only one sperm, not subject to classic, or indeed any, tests for the procedure to be successful. Over the past decade, a number of laboratory tests have been developed to determine properties of sperm function. These include quantitative sperm motion parameters, capacitation, basal and induced acrosome reactions, sperm–zona pellucida interactions and nuclear and mitochondrial sperm DNA but few have been adopted into routine clinical use. International collaborations should be initiated to develop clinically relevant molecular and functional tests with agreed protocols and clinical thresholds as a matter of urgency.

Relationship between human sperm-hyaluronan binding assay and fertilization rate in conventional in vitro fertilization

BACKGROUND

Sperm-hyaluronan-binding assay (HBA) is one of the commercial kits being marketed for routine testing of sperm maturity and fertility. However, there is no report of whether the HBA can provide additional information over standard semen analysis for sperm-fertilizing ability. The objective of this study was to investigate the relationship between HBA and fertilization rate in conventional IVF.

METHODS

A total of 175 IVF patients with > or = 3 mature oocytes inseminated were included in the study. Both the standard semen analysis and the HBA were performed on the same ejaculated sperm samples used for IVF treatments. Relationships between the semen analysis and the HBA results and fertilization rate were analysed by both the Spearman test and the multivariate logistic regression analysis.

RESULTS

Both total and progressive sperm motility and normal morphology were highly correlated with HBA scores. While both normal sperm morphology and HBA scores were statistically significantly related to fertilization rates, the HBA was less significant than normal sperm morphology. The HBA does not provide additional information for identifying patients with a poor fertilization rate.

CONCLUSION

HBA is highly significantly correlated with sperm motility and morphology but is less significant than sperm morphology in relation to the fertilization rate in IVF. Thus, the clinical predictive value of HBA for sperm-fertilizing ability in vitro is limited.

Is quality assurance in semen analysis still really necessary? A view from the andrology laboratory

Quality assurance (QA) is a fundamental part of laboratory medicine, of which internal and external QA (proficiency testing) is an important part. In a recent debate article published in Human Reproduction, it was argued that it was no longer necessary for semen analysis to be subject to QA, primarily because it is now being performed robustly and there is little evidence that it has any real clinical value. In response to this argument, it is suggested here that although there may have been some improvements in the training of laboratory scientists, recent studies have shown that the techniques of semen analysis are still poorly implemented at many locations. Moreover, as the impact of the introduction of QA into the andrology laboratory begins to take effect, there are a growing number of studies showing that the results of semen analysis do correlate well with natural conception and some assisted reproductive technologies. However, since the processes of QA are central to the principles of total quality management, which in turn underpins the process of laboratory accreditation, QA needs to remain in the andrology (and embryology) laboratory so that they can achieve the same accredited status as medical laboratories in other disciplines.

Influence of analytical and biological variation on the clinical interpretation of seminal parameters

Quality assurance in semen analysis has been questioned recently in this journal. Based on the limited capacity of seminal parameter in the determination of fertility, the authors advocated abandoning methods of quality assurance in semen analysis for clinical situations. In this article, we explore arguments as to why quality assurance in semen analysis for clinical use is not 'a waste of time'. Imprecision and within-subject biological variations are the two major components involved in the dispersion of seminal parameter results obtained by analysis of a semen sample from an individual. As within-subject biological variation is constant across geography, time and population, imprecision is a very important factor in the quality of laboratory test results. We analyse this influence on various seminal parameters and observe that there is an amount of error that can be tolerated without invalidating the medical usefulness of seminal parameter determination. However, there is a maximum allowable analytical error above which the medical usefulness of seminal parameter results is invalidated. The level of performance required to facilitate clinical decision-making is termed quality specification. We comment on different strategies to define the maximum allowable analytical error.

Is quality assurance in semen analysis still really necessary? A spermatologist's viewpoint

In a provocative article to this Journal, Anne Jecquier, an eminent andrologist who, more than 20 years ago, was a prime mover in suggesting the need for quality assurance (QA) in andrology laboratories, has now proposed that the QA schemes may no longer be needed. Here I reply to that proposition, largely by agreeing that, since the QA schemes have brought about higher technical standards in laboratories, Anne Jecquier's assertion is possibly true. However, vigilance is still needed in discriminating between unproductive investment of time and energy in the refinement of tests that may offer little information about fertility, and maintaining technical standards such that where necessary they provide the requisite information. Thus, although it may not matter in practice whether a sperm concentration is estimated as 100 or 200 x 10(6)/ml, distinguishing between 25 and 100 x 10(6)/ml would probably influence a clinician's treatment decisions. Anne Jecquier also suggested that sperm function tests have limited predictive value in terms of fertility assessment. While I agree that this is largely true at present, I also argue that these tests are probably not developed to their full potential. I am optimistic that tests to distinguish and quantify the population of fertilization-competent sperm within an ejaculate will eventually become available.