How has the external quality assessment/proficiency testing of semen analysis been developed in the past 34 years: a review.

Male infertility has become an important issue of global concern. Semen analysis is the cornerstone of male fertility assessment. External quality assessment (EQA) of sperm concentration, motility, and morphology is widely recognized in the world. However, over the past 34 years, the implementation of EQA for semen analysis has varied across different countries, and there is no global consensus. The goal of this paper is to first explore the overall development of EQA during this period. Secondly, it aims to discuss the extent of difference of participating laboratories in different countries. Finally, the paper examines the differences in EQA programs developed by various EQA providers in order to seek a global standard. In total, 29 papers met the inclusion criteria and were included in this review. There is inconsistent in the implementation of EQA across different countries, and there is no global consensus. Policies for EQA of semen analysis vary from country to country. Some countries mandate laboratory participation, while others permit voluntary involvement. Different EQA organizers choose different ways to calculate assigned value and acceptance limits. The coefficient of variation (CV) for each EQA item was large. The CVs of concentration, motility, morphology, and viability were 12.7-138.0 %, 17.0-127.0 %, 7-375 %, and 6-41.1 %, respectively. The results of the semen analysis varied considerably among the participating laboratories. The collaborative efforts of national policymakers, EQA organizers, and all participating laboratories are essential to improving the current situation.