Objective: To evaluate the quality of the donor semen in Chongqing Human Sperm Bank and the influence of age on semen parameters.
Methods: We collected semen samples from 899 donors in Chongqing Human Sperm Bank and divided them into five groups according to the age of the semen donors: 22－25, 26－30, 31－35, 36－40, and >40 years old. Using the Makler Counting Chamber, we measured the semen volume, percentage of progressively motile sperm (PMS), total motile sperm, sperm concentration, total sperm count per ejaculate, and percentage of morphologically normal sperm (MNS). Then, we compared the semen parameters obtained with the fifth percentile and median reference values published in the WHO Laboratory Manual for the Examination and Processing of Human Semen-5th Ed (WHO 5th Ed) and among different age groups using the Kruskall-Wallis H test.
Results: The semen volume (1.8 ml), sperm concentration (25.0 × 10⁶/ml), total sperm count (100.7 × 106/ejaculate) and MNS (4.3%) in the semen samples of the 899 donors were obviously higher than the fifth percentile values published in the WHO 5th Ed, and so were the first three parameters (4.0 ml, 88.0 × 10⁶/ml, and 333.7 × 106/ejaculate) than the WHO median reference values. PMS (31.0%) and total motile (38.0%) were lower than the WHO fifth percentile values and so was MNS (11.6%) than the WHO median reference value. PMS (55.0%) and total motile sperm (61.0%), however, were coincident with the median reference values of WHO 5th Ed. Statistically significant differences were observed among the 22－25, 26－30, 31－35, 36－40 and >40 years old groups in perm concentration (88.0 ［1.0－270.0］ vs 96.0 ［5.0－335.0］ vs 100.0 ［3.0－200.0］ vs 105 ［15.0－225.0］ vs 90.0 ［22.0－159.0］ × 10⁶/ml, P < 0.05), but not in the semen volume, PMS, total sperm motility, total sperm count or MNS (P > 0.05).
Conclusions: The donor semen in Chongqing Human Sperm Bank is generally of high quality. Sperm concentration significantly increases with age but decreases in men aged >40 years.
目的： 了解重庆市人类精子库捐精志愿者精液质量，探讨年龄对精液质量的影响。 方法： 收集重庆市人类精子库899例捐精志愿者精液样本，根据年龄分为5组：22～25岁、26～30岁、31～35岁、36～40岁、>40岁，使用Makler板人工计数，分别进行精液体积（ml）、前向运动（PR）精子百分率(PR%)、精子总活力［（PR+NP）%］、精子浓度、精子总数及正常形态精子百分率检测，并与世界卫生组织《人类精液检查与处理实验室手册》第5版(以下简称WHO第5版）的参考值进行比较；各年龄段的精液参数指标采用中位数表示，比较精液质量差异。 结果： 899例捐精志愿者精液参数第5百分位数精液体积（1.8 ml）、精子浓度（25.0×10⁶/ml）、精子总数（100.7×106）和正常形态精子百分率（4.3%）均高于WHO第5版第5百分位数参考值，PR%（31.0%）、(PR+NP)%（38.0%）低于WHO第5版第5百分位数参考值；精液参数中位数精液体积（4.0 ml）、精子浓度（88.0×10⁶/ml）、精子总数（333.7×106）高于WHO第5版中位数参考值，正常形态精子百分率（11.6%）低于WHO第5版中位数参考值，PR%（55.0%）和(PR+NP)%（61.0%）与WHO第5版中位数参考值一致?gt;优ǘ仍?2~25岁、26~30岁、31~35岁、36~40岁、<40岁年龄组分别为88.0（1.0～270.0）×10⁶/ml、96.0（5.0～335.0）×10⁶/ml、100.0（3.0～200.0）×10⁶/ml、105.0（15.0～225.0）×10⁶/ml、90.0（22.0～159.0）×10⁶/ml，在各年龄组间有显著性差异(P<0.05)，精液体积、PR%、(PR+NP)%、精子总数和正常形态精子百分率在各年龄组间无显著性差异(P>0.05)。结论： 重庆市人类精子库捐精志愿者精液质量普遍较好。随着年龄的增长，精子浓度呈显著性升高，但>40岁以后精子浓度呈显著性下降。.
Keywords: Chongqing area; age; semen quality; sperm donor.