精液分析:精子数目、形态及功能

Semen Analysis with Regard to Sperm Number,Sperm Morphology and Functional Aspects

新版《世界卫生组织精液分析实验室技术手册》(简称手册)较旧版有所改进。改进之一就是用较低的新参考值取代原来20×106/mL的精子密度参考值。新参考值是经过对配偶妊娠等待时间≤12个月的男性精液进行统计分析得出的。第3版和第4版手册中精子前向性运动分级的规定缺乏循证医学依据,因此应废除。但新版本中的评估方法也缺乏循证医学依据,其合理性令人难以理解。但为了避免重新使用第1版手册(1980)中的精子活动力评估系统,只能勉为其难地使用当前的方法。强行推荐所谓的"Tygerberg严格精子形态学标准"是因为委员会的部分成员偏袒该标准,并无循证医学依据。这种推荐将阻碍男科学这一科研领域的进步和发展。WHO手册相当重要,但遗憾的是其推荐的精子活动力及精子形态学等重要参数的评估标准仍缺乏循证医学的支持。

The new World Health Organization （WHO） Manual for Semen Analysis contains several improvements. One is that the 20 million spermatozoa per mL paradigm has been ousted in favour of proper calculations of lower reference limits for semen from men, whose partners had a time-to-pregnancy of 12 months or less. The recommendation to grade the progressive motility as described in the third and fourth editions of the WHO manual was not evidence-based, and WHO was therefore motivated to abandon it. However, the new recommendation is not evidence-based either, and it is difficult to understand the rational for the new assessment. It may have been a compromise to avoid returning to the rather robust system recommended in the first edition（1980）. The unconditional recommendation of the＇Tygerberg strict criteria＇ is not evidence-based, and seems to be the result of an unfortunate bias in the composition of the Committee in favour of individuals known to support the ＇strict criteria＇ method. This recommendation will have negative effects on the development of andrology as a scientific field. Given the importance of the WHO manual, it is unfortunate that the recommendations for such important variables, as motility and morphology, lack evidencebased support.