From the Guidelines
Semen Analysis (SA) is a crucial evaluation in the diagnosis of male infertility, and it is recommended to assess a combination of several ejaculate parameters for better predictive value of fertility success.
Key Components of Semen Analysis
- The initial evaluation for male factor infertility should include a physical examination (PE) performed by an examiner with appropriate training and expertise, a reproductive history, and at least one properly performed (high quality) semen analysis 1.
- A full evaluation by a urologist or other specialist in male reproduction should be done if the initial screening evaluation demonstrates an abnormal PE, an abnormal male reproductive or sexual history, or an abnormal semen analysis is found 1.
- Analysis of a single ejaculate is sufficient to determine the most appropriate investigation and treatment pathway although semen analysis could be repeated if one or more abnormalities are found 1.
Importance of Semen Analysis Parameters
- Assessment of a combination of several ejaculate parameters is a better predictor of fertility success than a single parameter 1.
- The predictive value of semen analysis for reproductive outcome is better using a combination of several parameters compared to a single semen analysis parameter 1.
Clinical Value of Semen Analysis
- Semen analysis is only part of the investigation of the man and a number of other attributes contribute to his fertility potential 1.
- There is a substantial overlap in the distribution of semen analysis results in fertile men and those from men in infertile couples, making it challenging to determine fertility potential based on semen analysis alone 1.
Recommendations for Semen Analysis
- The initial evaluation for male factor infertility should include a PE, reproductive history, and at least one properly performed semen analysis 1.
- A full evaluation by a urologist or other specialist in male reproduction should be done if the initial screening evaluation demonstrates an abnormal PE, an abnormal male reproductive or sexual history, or an abnormal semen analysis is found 1.
- Analysis of a single ejaculate is sufficient to determine the most appropriate investigation and treatment pathway although semen analysis could be repeated if one or more abnormalities are found 1. Some key points to consider when evaluating semen analysis results include:
- The quality of the laboratory testing, which can significantly impact the diagnostic value of semen analysis 1.
- The potential for variability in semen parameters due to factors such as abstinence, which can be mitigated by adopting and adhering to appropriate practices and WHO procedures 1. It is essential to consider these factors when interpreting semen analysis results and making decisions about further evaluation and treatment.
From the Research
Evaluation of Semen Analysis (SA)
The evaluation of Semen Analysis (SA) is a crucial step in assessing male fertility, providing information on the functional status of the seminiferous tubules, epididymis, and accessory sex glands 2. The methods for evaluating human semen are standardized by the World Health Organization (WHO), which periodically releases manuals with specific protocols and reference standards 3.
Limitations and Methodology
However, semen analysis has limitations as a surrogate measure of a man's ability to father a pregnancy, and methodology issues can affect the results 2. The 2010 WHO criteria for human semen characteristics were markedly lower than those previously reported, which may impact the management of male infertility 2. To improve the interpretation of semen analysis results, a template that incorporates the distribution of semen characteristics of recent fathers in centiles, rather than solely minimum thresholds, could be useful 2.
Advances in Semen Evaluation
Recent advances in evaluating sperm-specific quality characteristics and methodologies have improved the assessment of male fertility 4. Computer-assisted sperm analyzers (CASA) and flow cytometric analysis provide precise information on sperm morphology and function, while profiling fertility-related biomarkers in sperm or seminal plasma can help predict fertility 4. The identification of sperm proteins and diagnosis of DNA damage has contributed to a better understanding of sperm physiology and molecular anomalies associated with male infertility 4.
Quality Control and Quality Assurance
Standardized laboratory procedures, quality control, and quality assurance are essential for accurate semen analysis in the evaluation of infertile males 5. Both manual and automated semen analysis require quality control and quality assurance to ensure reproducible results, and laboratory technicians' performance should be evaluated biannually 5.
WHO Manual for Human Semen Analysis
The Sixth Edition of the WHO Manual for Human Semen Analysis, published in 2021, provides updated guidelines for procedural standardization and reference values worldwide 6. The new edition has made the analysis of basic semen parameters more robust, taking into account criticisms and grey areas of previous editions, and introduces the concept of "decision limits" instead of reference thresholds 6. However, no decision limits are proposed for basic semen parameters or extended or advanced parameters, which may impact its utility in clinical practice 6.
Key Points
- Semen analysis is a crucial step in assessing male fertility 2
- The WHO provides standardized methods for evaluating human semen 3
- Semen analysis has limitations as a surrogate measure of male fertility 2
- Recent advances in sperm evaluation have improved the assessment of male fertility 4
- Quality control and quality assurance are essential for accurate semen analysis 5
- The Sixth Edition of the WHO Manual for Human Semen Analysis provides updated guidelines for procedural standardization and reference values 6