Lessons learned from a sperm morphology quality control programme

Human sperm morphology assessment since 2010: experience of an Australian external quality assurance programme

RESEARCH QUESTION

Which classification criteria of sperm normality were used after the publication of the World Health Organization (WHO) 5th Edition manual (WHO5), and how did the laboratories perform?

DESIGN

Semen samples were sent to enrolled laboratories over a 10-year period for the determination of the proportion of spermatozoa with normal morphology. The coefficient of variation was used to indicate the level of precision between laboratories.

RESULTS

Before the publication of WHO5, at least six different classification criteria were in use. After 2010, WHO5 was quickly adopted, with 50% of laboratories using WHO5 criteria after the first 2 years, increasing to 94% after 10 years. Reported normal forms by WHO3 and WHO4 users remained consistent; however, the morphology results for each distribution declined significantly over time for WHO5 users (P < 0.001), suggesting laboratories were becoming stricter in their identification of normal spermatozoa. The precision of WHO5 users improved over time as shown by a steady decline in the coefficients of variation.

CONCLUSIONS

The introduction of WHO5 resulted in the effective adoption of its morphology classification system, with laboratories showing improved between-laboratory variation over time; however, the identification of normal forms by WHO5 users over time was inconsistent, as laboratories became stricter. Given the reduction in reported normal forms by WHO5 users, it seems that increased training of laboratory personnel or the consideration of validated objective automated analysers in the assessment of sperm morphology would seem warranted.

How accurate is sperm morphology as an indicator of sperm function?

Sperm morphology has been consistently correlated with fertilisation success or failure. The clinical relevance of the percentage normal spermatozoa has been a widely discussed topic amongst infertility specialists and scientists. This study aimed to evaluate the role of sperm morphology as an indicator of additional sperm functions among 114 andrology referrals. The sperm functions that were investigated included chromatin packaging quality (CMA3 test (n = 109), zona-induced acrosome reaction (ZIAR test; n = 36), hemizona assay (HZI; n = 36) and progressive motility (n = 47). Chromatin packaging quality had a negative and significant (P = 0.0001, r = -0.74) correlation with the percentage normal spermatozoa, while progressive motility had a significant and positive correlation (P = 0.0001, 0.59). Accurate sperm morphology scoring as described by the WHO 2010 manual can therefore be used as an indicator of specific sperm functions.

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.

Reducing inter-observer variability in embryo evaluation by means of training courses

PURPOSE

To study the utility of a training session offered to junior embryologists, comparing the results obtained with those reported by a group of senior embryologists.

METHODS

The 62 junior embryologists participanting were asked to decide on the quality of the embryos and theg clinical decision to be taken.

RESULTS

The junior embryologists' success rate following the training course was significantly higher than before for embryo classification (48.4% ± 20.4 vs. 59.7% ±16.7) (p < 0.05) and for clinical decision (54.7% ± 19.6 vs. 68.7% ± 17.6) (p < 0.005). Comparison of the degree of agreement between the categories assigned by the junior embryologists and those assigned by consensus among the group of senior embryologists revealed kappa values of k = 0.32 before the course and of k = 0.54 after it. The comparison between pre- and post-training junior and senior embryologists also reflected an improvement in the kappa index for clinical decision, from k = 0.54 to k = 0.68.

CONCLUSIONS

Training courses are shown to be an effective tool for increasing the degree of agreement between junior and senior embryologists.

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.