精液常规参数初检合格后不同时间点再分析结果及其与精子DNA损伤的关系

目的:探讨完全液化且常规参数初检合格的精液标本,于不同时间再分析的结果差异,及精子DNA碎片化指数(DFI)与精子活动力改变的相关性。方法:选取127份符合纳入标准的精液标本,分别于取样后15、30、60 min时采用计算机辅助精液分析(CASA)系统进行分析。精子形态分析采用Shorr染色法,吖啶橙试验(AOT)检测DFI。结果:3个时间点精子浓度、a级和b级精子百分率均无统计学差异(P>0.05)。取样15 min时a+b和a+b+c级精子百分率显著高于30和60 min时的结果(P<0.05),后两者间无统计学差异(P>0.05)。不同时间精子活动力各项指标中,至少有1项由"正常组"变为"异常组"的发生率为25.2%,两组间DFI和形态学无统计学差异(P>0.05)。取样后15到60 min变化的精子活动力指标中,a、a+b、a+b+c级下降值与DFI存在正相关性(P<0.05)。结论:取样后15 min内完全液化并初查参数合格的精液标本,30～60 min内复查时,a级和b级精子百分率波动并无显著差异,而a+b级及a+b+c级精子则可能显著下降,精子活动力指标可能出现异常。故应至少进行2次精液分析,综合评估生育力。如2次结果差异较大,尤其是a级精子百分率下降幅度较大,则可能与精子DNA损伤有关,需进一步行精子DNA损伤检测。

Seminal parameters at different times of reanalysis of the normal semen samples detected in initial examination and their correlation with sperm DNA damage

Objective: To investigate the differences in semen quality at different times of reanalysis and the correlation of sperm DNA fragmentation index(DFI) with sperm motility alteration using semen samples completely liquefied and normal in initial examination.Methods: We analyzed 127 semen samples up to the inclusion criteria with the computer-assisted semen analysis(CASA) system at 15,30 and 60 min after semen collection,and obtained sperm morphology parameters and DFI by Shorr staining and acridine orange test(AOT),respectively.Results: Sperm concentration,and the percentages of grades a and b sperm showed no statistically significant differences at the three time points(P>0.05).The percentages of grades a+b and a+b+c sperm were significantly higher at 15 min than at 30 and 60 min after semen collection(P<0.05),but with no significant difference between the latter two time points(P>0.05).The incidence of alternation from normal to abnormal in at least one index of sperm motility at different times was 25.2%,but there were no significant differences in sperm DFI and morphology between the normal and abnormal groups(P>0.05).Among the altered parameters of sperm motility from 15 to 60 min,the percentages of grades a,a+b and a+b+c sperm were all positively correlated with sperm DFI(P<0.05).Conclusion: Semen samples completely liquefied within 15 min after collection and normal in initial examination,when reanalyzed at 30 and 60 min,showed significant decreases in the percentages of grades a+b and a+b+c sperm,but not in the percentages of grades a and b sperm,and the parameters of sperm motility might be abnormal.Thus,at least 2 sperm analyses are required for a comprehensive evaluation of fertility.Significant difference between the results of the two analyses,and particularly a markedly reduced percentage of rapidly progressive sperm,might indicate sperm DNA damage,and thus the necessity of sperm DNA damage detection.