Given the ongoing concerns about the apparent decline in male fertility over the last 50 years, one might be forgiven for thinking that the examination of human semen in the laboratory was now an exact science. This examination is a crucial part of the initial assessment of men reporting fertility problems. However, whilst we have made major progress in agreeing the methodology to be used in the andrology laboratory - largely through the publication of a laboratory manual by the World Health Organisation (WHO) - it seems we still have far to go.
Given that it is over six years since the publication of the 4th edition of the WHO manual (published in 1999), we decided to survey medical laboratories to see how they had implemented the techniques recommended to undertake just one aspect of semen analysis: sperm morphology assessment. This assessment of the size and shape of sperm is arguably one of the most difficult aspects of semen analysis to perform by laboratory scientists. But the literature suggests that, if it is done robustly, it is highly predictive of fertility: given that only sperm with a specific size and shape are thought to be able to enter cervical mucus following natural conception, or be able to bind to the human egg either in vivo or in IVF.
However, the results of our survey, to be published in the journal Human Reproduction, were somewhat surprising. They showed that of the 37 laboratories that responded, 70 per cent counted too few sperm to make a statistically reliable estimation of sperm morphology; 43 per cent tried to observe sperm that were not stained on a microscope slide; 22 per cent of laboratories used a stain that hadn't been recommended by WHO, and 16 per cent of laboratories used an inadequate magnification on the microscope. As such, when taking into account the additional recommendations for internal and external quality control measures, only 5 per cent of the responding laboratories were fully compliant with all the WHO recommendations for undertaking this aspect of semen analysis.
The laboratories that responded to the survey fell in almost equal numbers into those that could be defined as 'general laboratories' (i.e. those that did semen analysis as part of other diagnostic work) and 'specialist laboratories' (i.e. those linked to IVF units or sperm banks). A reasonable assumption might be that 'specialist laboratories' would fair better in terms of compliance than 'general' ones, given that they potentially have' better access to current literature as well as specific training programmes in assisted conception. However, the data shows that this is not the case, with an almost equal number of laboratories in each group failing to meet the WHO recommendations.
This survey is not merely an academic - or perhaps pedantic - exercise to examine the minutiae of an aspect of laboratory methodology: the results are perhaps more wide ranging and may be of great significance to patients. There has been ongoing debate about the importance of measures derived at semen analysis and whether they are at all predictive of outcome of spontaneous conception or assisted conception treatments such as IVF. Similarly, there is widespread concern about a possible decline of male fertility as seen in semen quality. However, the literature concerning both areas sometimes appears confusing with the results of many studies all too often apparently contradicting each other. But is that a surprise, if laboratories undertaking semen analysis ignore international guidelines so blatantly?