One-step disposable chambers for sperm concentration and motility assessment: how do they compare with the World Health Organization's recommended methods?

The World Health Organization suggests that 'one-step' type disposable cham bers lack the accuracy and precision of the haemocytometer method for asses sing sperm concentration, The purpose of this particular study was to compa re sperm concentration measurements and motility using the Neubauer(R) haem ocytometer with those obtained using three 'one-step' methods: the Microcel l(R) slide, Leja(R) slide and a plain glass slide with a 22 x 22 mm coversl ip. A total of 200 sperm concentration measurements and 100 motility assess ments were performed on all chambers. Paired comparisons showed enormous di screpancies between the counts, particularly between the Neubauer(R) and ot her chambers (P < 0.0001). This discrepancy was less pronounced in oligozoo spermic samples, and samples with low (<30% progression) motility but more pronounced in normozoospermic samples and those with good motility (>50% pr ogression). In addition, concentration assessments from a fresh undiluted a nd unfixed semen sample on the Microcell(R) slide were found to be signific antly lower than both fixed counts on the same slide (P = 0.011) and the in itial laboratory reading on the Neubauer(R) chamber (P = 0.009). No differe nces were observed in progressive motility between the different chambers a nd a plain glass slide. There appears to be little comparison between the h aemocytometer and either re-useable or disposable one-step chambers. The un fortunate consequence of this is that diagnostic semen analysis and guideli nes for allocation of patients to appropriate treatment groups will vary fr om centre to centre, depending on the method used and may, on occasion, be erroneous.