Sperm motility index

Double-blind prospective study comparing two automated sperm analyzers versus manual semen assessment

PURPOSE

Despite controversy regarding its clinical value, male fertility investigation mainly relies on semen analysis. Even though reference guidelines are available, manual sperm analysis still suffers from analytical variability, thus questioning the interest of automated sperm analysis systems. The aim of this study is to compared automated computerized semen analysis systems (SQA-V GOLD and CASA CEROS) to the conventional manual method in terms of accuracy and precision.

METHODS

We included 250 men in this double-blind prospective study. The SQA-V GOLD (Medical Electronic Systems) and CEROS, CASA system (Hamilton Thorne) were compared to the standard manual assessment based on the WHO 5th Edition. The main outcome measures were sperm concentration, total sperm number, total motility, progressive motility, non-progressive motility, morphology, motile sperm concentration (MSC) and progressively motile sperm concentration (PMSC) with the three methods.

RESULTS

Statistical analysis of the test results from the automated systems and the manual method demonstrated no significant differences for most of the semen parameters. The Spearman coefficients of rank correlation (rho) for CASA and the SQA-V GOLD automated systems vs. the manual method were: Sperm concentration (0.95 and 0.95), total sperm number (0.95 and 0.95), MSC (0.94 and 0.96) and PMSC (0.94 and 0.93) correspondingly. Concerning sperm morphology, both automated systems demonstrated high specificity (Sp) and negative predictive values (NPV), despite significantly different medians (CASA: 83.7 % for Sp and 95.2 % for NPV, SQA-V: 97.9 % for Sp and 92.5 %). The highest precision (lowest 95 % confidence interval for duplicate tests) for all semen variables was found in the SQA-V GOLD.

CONCLUSIONS

The advantages of using automated semen analysers are: Standardization, speed (lower turnaround time), precision, reduced potential for human error, automated data recording and less need for highly skilled professionals to run the systems. The disadvantages of using automated systems are: notably the problem with testing some atypical samples and the inability to perform an assessment of morphology abnormalities. Based on the results of this study, the SQA-V Gold demonstrated better agreement vs. the manual method. In conclusion, automated semen analyzers can be used for routine semen analysis providing rapid clinically acceptable results with higher precision, and positively impacting laboratory standardization.

A computerized spectrophotometric instrumental system to determine the “vertical velocity” of sperm cells: A novel concept

BACKGROUND

The presently available cell motility-analyzers measure primarily the "horizontal" velocity and there is no instrument available for "vertical" velocity measurement. This development was based on the turbidimetric method of sperm motility analysis.

METHODS

Sperm was layered at the bottom of the cuvette containing buffer solution and exposed to the spectrophotometric light path at different heights to track the vertically moving sperms. The vertical movement was materialized with the development of an electromechanical up-down movement devise for the cuvette accomplished with the help of a cuvette holder-stepper motor-computer assembly. The entire system was controlled by the necessary motion control, data acquisition, and data processing software developed for cuvette movement and data analysis.

RESULTS

Using goat sperm as the model a unique computer-based spectrophotometric system has been developed for the first time to determine the average "vertical" velocity of motile cells.

CONCLUSIONS

Undertaking upward movement against gravity is much tougher as compared with horizontal movement. Consequently average vertical velocity is expected to be a much better identifying parameter for assessing semen and other motile cell quality. The novel instrumental system developed by us has thus the potential for immense application in human infertility clinics, animal-breeding centres, centres for conservation of endangered species, and also for research work on vertical velocity of spermatozoa and other motile cells, such as bacteria, protozoa, etc.

Validation of the sperm quality analyzer (SQA) for dog sperm analysis

In the present study, a simple and inexpensive unit (the Sperm Quality Analyzer-SQA), was evaluated for dog sperm analysis. Our objective was to propose a cheap, accurate and convenient device to be used in veterinary practices involved with dog fertility assessment and artificial insemination. The device was tested by analyzing repeatability and accuracy at different sperm concentrations and motility characteristics. The Sperm Motility Index (SMI), a numeric index provided by the SQA, was compared with the results obtained using a computer-aided sperm analyzer (Hamilton Thorn IVOS 10). The correlation between SMI and some sperm parameters as well as predictive values of the SMI were established. The dog sperm data provided by the SQA were consistent and repeatable (coefficient of variability below 10% for all concentrations tested). The SMI was significantly dependant on motile sperm concentration and a positive significant correlation was established for the different motile sperm concentrations from a concentration of 25 x 10(6) up to over 200 x 10(6) cells/mL. Zero motility did not affect SMI because non-motile cells, regardless of their concentration, do not cause any fluctuations in the optical density (OD). Over the tested 200 x 10(6) cells/mL value, a correlation still could be observed but it was not statistically significant, possibly because of a saturation of the system. In dog semen, the correlation is better between SMI values and the number of motile spermatozoa than with the overall motile concentration. Based on this observation, a predictive value was given to the SMI allowing for a sorting of dog ejaculates in 3 sperm categories (SMI <100, 100<SMI<250, SMI>250) each characterized by a range of sperm number and motility. If a positive correlation between the SMI categories and fertility has been demonstrated in humans, such a correlation needs to be established in dogs.