Objective: To investigate the change trends of sperm quality with seasonal variations among the volunteers of sperm donors in Beijing area, as well as the relationship between two parameters.
Methods: Semen data from the volunteers of sperm donors in Human Sperm Bank of Peking University Third Hospital were collected using a retrospective study method. The subjects were divided into 4 seasonal groups based on the lunar solar terms and the time of sperm donation. The data were assessed to find whether there were differences in semen parameters among different seasonal groups, and to analyze the change trends and the influence of seasonal factors on semen parameters.
Results: A total of 21 174 semen parameter data were analyzed. Firstly, to analyze all data as a whole, in spring, summer, autumn and winter groups, sperm concentration was (106.04±59.67)×106/mL, (97.61±47.41)×106/mL, (100.18±47.17)×106/mL, (100.59±38.68)×106/mL, respectively, and the spring group was significantly higher than the other 3 seasonal groups (P < 0.001); proportion of progressive motility sperm (PR) was 56.49%±12.76%, 58.02%±13.65%, 58.05%±12.36%, and 57.66%±12.61%, respectively, spring group was lower than the other three seasonal groups, and summer group was better among the latter (P < 0.001). There was no difference in normal rate of sperm morphology among the four seasonal groups. The qualified rate of sperm donors in the winter group was higher than that in the other three seasons groups (P < 0.01), while the qualified rate in the summer group was lower than that in the other three seasons groups. In addition, the semen parameters of the volunteers during the screening period and the official sperm donation period were analyzed respectively, which revealed that sperm concentration of spring group was higher than that of summer and winter groups, and PR was lower than that of summer and autumn groups. On account of the semen parameters of official sperm donation period, multiple linear regression analysis found that season was the main factor affecting sperm concentration, the average sperm concentration in spring group was about 6×106/mL higher than in winter group, but PR was 2.9% lower in spring group compared with autumn group (all P < 0.05).
Conclusion: Season was the influencing factor of semen quality of sperm donors in Beijing area. We recommend spring and winter may be the preferred seasons for sperm donation.
目的: 探索和分析北京地区捐精志愿者的精液质量随季节的变化规律以及两者之间的相关性。
方法: 应用回顾性研究方法，收集北京大学第三医院人类精子库捐精志愿者人群的精液数据，按照农历节气和捐精时间进行4个季节分组，比较不同季节分组之间精液参数的差异，分析变化规律以及季节因素对精液参数的影响。
结果: 共纳入和分析21 174例精液常规检查数据。将全部数据整体分析，春、夏、秋、冬季组的精子浓度分别为(106.04±59.67)×106/mL、(97.61±47.41)×106/mL、(100.18±47.17)×106/mL、(100.59±38.68)×106/mL，春季组明显高于其他3个季节组(P＜0.001)；前向运动精子百分率(progressive motility，PR)分别为56.49%±12.76%、58.02%±13.65%、58.05%±12.36%、57.66%±12.61%，春季组低于其他3个季节组，夏季组较好(P＜0.001)；精子正常形态率4个季节组间差异没有统计学意义；冬季组的捐精志愿者合格率高于其他3个季节组(P＜0.01)，而夏季组则低于其他3个季节组。将筛选期和正式捐精期志愿者的精液参数分别进行分析，均显示春季组的精子浓度高于夏季和冬季组，PR低于夏季和秋季组。基于正式捐精期精液参数，多元线性回归分析表明季节是影响精子浓度的主要因素，春季组的平均精子浓度比冬季组约高6×106/mL，但春季组的PR比秋季组低2.9%(均P＜0.05)。
结论: 季节是北京地区捐精志愿者精液质量的影响因素，推荐春冬两季适宜捐精志愿者积极捐献精子。
Keywords: Seasons; Semen quality; Sperm count; Sperm donors; Sperm motility.