Over the past 40 years, the WHO laboratory manual for the examination and processing of human semen has become a vital guide for laboratory examinations, widely translated and used extensively by clinical and research laboratories throughout the world.
The manual has been regularly revised since first publication in 1980, as new techniques are validated and made available for clinical and research purposes. Now, following extensive expert and public review, the sixth edition of this important tool has been published.
The updated manual will help scientists, technicians, laboratory experts and healthcare workers worldwide to safeguard the quality of research and clinical use of human semen in laboratory settings – ultimately improving sexual and reproductive health.
Reliable information is essential for effective research and quality care
High-quality laboratory services are crucial for ensuring the value of research on health. Effective analysis and comparison of results across laboratories helps to ensure that healthcare workers receive high quality information, which in turn helps them provide the best quality care.
The sixth edition of the WHO laboratory manual for the Examination and processing of human semen replaces the 2010 version. It provides important information on semen examination and preparation for clinical evaluation, assessment, cryopreservation, quality control in the semen analysis laboratory, and laboratory examination in the investigation of male sexual and reproductive health.
Ian Askew, Director of the WHO Department of Sexual and Reproductive Health and Research (SRH) including the UN Special Programme HRP states, "The sixth edition of the WHO Manual for the Laboratory Examination and Processing of Human Semen will benefit programmes that seek to improve quality and access to sexual and reproductive health, including fertility care, especially among males, thereby supporting countries' efforts to attain the Sustainable Development Goals."
Why semen examination?
Semen analysis is critical in both clinical practice and epidemiological research. Assessing how male reproductive organs function and whether there are any pathologies (abnormalities) in the genital tract can both enable appropriate treatment for male sexual and reproductive ill health, and monitor response of individuals to respective treatments.
Effective examination of semen by laboratory workers can also inform the appraisal of fertility potential. This can help inform the choice of suitable treatment for couples living with infertility. It can also be used to measure the efficacy of male contraception.
Semen and fertility
When a couple seeks fertility care, analysis of semen can help to guide the clinician to determine how to proceed with further investigation and management. It is worth noting however, that for an individual patient, a semen analysis can never give confirmation of fertility; their fertility potential depends also on several other parameters and the fertility potential of their partner. This means it is only the couple (and not the individual) that can be defined as either fertile or infertile.
The updated WHO laboratory tool can help to provide information to facilitate the interpretation of the results, but it is not a guideline for clinical decisions on treatments for male factor infertility, or for use by the general public. Addressing infertility is an important part of realizing the right of individuals and couples to found a family, and WHO is in the process of developing global guidance on prevention, diagnosis and management of infertility.
Key updates in the sixth edition
The updated manual describes laboratory methods for examination of human semen, to contribute to global improvement in assessment of male sexual and reproductive function, fertility treatment and care.
It includes new and expanded sections on semen sample preparation, determining markers for infection, computer-aided sperm analysis, and processes for basic, extended, and advanced examination of human semen.
The manual was first published in response to a growing need for standardization of laboratory procedures and parameters. The sixth edition also strives to be user-friendly.
Updates include clear instructions and explanations on the order in which analyses should be performed when a semen sample is delivered to the laboratory, including Quality Control and External Quality Assessment. There are step-by-step procedures and checklists for the international community of laboratory technicians and scientists working with human semen.
This should also make global comparisons easier, for scientists evaluating the methods used in the manual.
Ultimately, this new edition will better-support researchers, health workers and scientists in turn support individuals to access the healthcare they need. As Igor Toskin, Scientist in the WHO Department of SRH, including HRP who led the experts that developed the manual, states,
"Universal access to laboratory services is essential to ensure that concerned populations can avoid the adverse health and socioeconomic consequences of sexual and reproductive ill health."
