辅助生育夫妇的男性年龄与精液质量的关联:一项横断面研究

Association between male age and semen quality in assisted reproductive technology cycles:a cross-sectional study

目的探讨辅助生育夫妇的男性年龄与精液质量及精子DNA碎片化指数(DNA fragmentation index,DFI)的关联性。方法采用横断面研究,收集2020年1月至2023年8月期间在武汉大学人民医院生殖医学中心因非男性因素行辅助生殖技术助孕治疗的3361例男性的临床资料。使用计算机辅助精液分析系统分析精液质量参数,使用精子核染色体结构检测分析DFI。将受试者按年龄分为20~29岁(A组)、30~39岁(B组)和40~59岁(C组)3组。采用多元线性回归和限制性立方样条(restricted cubic spline,RCS)法分析年龄与精液质量参数及DFI之间的关联。结果共纳入研究对象共3361例,年龄为(34.86±5.34)岁。B组和C组的精子前向运动率[(40.17±18.16)%、(37.83±16.96)%]及精子总活动率[(55.27±21.37)%、(53.09±21.14)%]显著低于A组[(43.78±18.16)%、(58.29±20.24)%];精子浓度[(78.96±63.04)×10^(6)/mL、(91.93±72.28)×10^(6)/mL]及DFI[(19.18±12.18)%、(21.73±12.52)%]显著高于A组[(71.75±57.44)×10^(6)/mL,(16.31±10.04)%],差异均有统计学意义(均P<0.001)。C组的精液量[(2.94±1.42)mL]显著低于A组[(3.28±1.43)mL]和B组[(3.15±1.58)mL],差异均有统计学意义(均P<0.05)。在调整了文化程度、体质量指数、吸烟、饮酒、禁欲天数后,多元线性回归结果显示:与A组相比,B组年龄与精子前向运动率(β=-3.055,95%CI:-4.879~-1.231)、精子总活动率(β=-2.366,95%CI:-4.516~-0.216)呈负相关,与精子浓度(β=7.752,95%CI:1.398~4.106)、DFI呈正相关(β=2.744,95%CI:1.526~3.961)。与A组相比,C组年龄与精液量(β=-0.379,95%CI:-0.565~-0.192)、精子前向运动率(β=-5.507,95%CI:-7.714~-3.301)、精子总活动率(β=-4.932,95%CI:-7.532~-2.331)呈负相关,与精子浓度(β=17.288,95%CI:9.604~24.973)、DFI(β=5.226,95%CI:3.753~6.699)呈正相关。RCS分析结果显示,年龄与精液量存在显著线性剂量-反应关系(P非线性检验=0.424),精液量随年龄增长而下降(P<0.001);年龄与精子浓度、精子前向运动率、精子总活动率及DFI呈非线性剂量-反应关系(P_(非线性检验)=0.003、P_(非线性检验)<0.001、P_(非线性检验)<0.001、P_(非线性检验)=0.004)。结论非男性因素行辅助生殖助孕术的男性中,年龄超过30岁与精液量、精子前向运动率及精子总活动率下降,与精子浓度及DFI上升显著相关。

Objective To investigate the correlation between the age of men and the quality of semen,as well as the DNA fragmentation index(DFI)in assisted reproduction couples.Methods A cross-sectional study was conducted,collecting clinical data from 3361 men who underwent assisted reproductive technology for fertility treatment at the Reproductive Medicine Center of Wuhan University People's Hospital from January 2020 to August 2023 due to non-male factors.Computer-assisted semen analysis system(CASA)was used to analyze semen quality parameters,and DFI was measured by Sperm Chromatin Structure Assay(SCSA).Patients were categorized into three groups based on age:20-29 years(group A),30-39 years(group B),and 40-59 years(group C).Multiple linear regression and restricted cubic spline(RCS)were used to analyze the correlation between age and semen quality parameters as well as DFI.Results The study included 3361 participants with an average age of(34.86±5.34)years.In groups B and C,sperm progressive motility[(40.17±18.16)%,(37.83±16.96)%]and total motility[(55.27±21.37)%,(53.09±21.14)%]were significantly lower than those in group A[(43.78±18.16)%,(58.29±20.24)%],sperm concentration[(78.96±63.04)×10^(6)/mL,(91.93±72.28)×10^(6)/mL]and DFI[(19.18±12.18)%,(21.73±12.52)%]were significantly higher than those in group A[(71.75±57.44)×10^(6)/mL,(16.31±10.04)%],semen volume was significantly lower in group C[(2.94±1.42)mL]than in groups B and A[(3.28±1.43)mL,(3.15±1.58)mL],with statistically significant differences(all P<0.05).After adjusting for education level,body mass index,smoking,alcohol consumption,and abstinence days,the results of multiple linear regression showed that compared with group A,the age of group B was negatively associated with sperm progressive motility(β=-3.055,95%CI:-4.879--1.231)and total motility(β=-2.366,95%CI:-4.516--0.216),while positively associated with sperm concentration(β=7.752,95%CI:1.398-4.106)and DFI(β=2.744,95%CI:1.526-3.961).Compared with group A,the age of group C was negatively correlated with semen volume(β=-0.379,95%CI:-0.565--0.192),sperm progressive motility(β=-5.507,95%CI:-7.714--3.301),and total motility(β=-4.932,95%CI:-7.532--2.331),while positively correlated with sperm concentration(β=17.288,95%CI:9.604-24.973)and DFI(β=5.226,95%CI:3.753-6.699).The results of RCS analysis indicated a significant linear dose-response relationship between age and semen volume(P non-linearity=0.424),showing a decline in semen volume with increasing age(P<0.001).Non-linear dose-response relationships were observed between age and sperm density(P_(non-linearity)=0.003),sperm progressive motility(P_(non-linearity)<0.001),total motility(P_(non-linearity)<0.001),and DFI(P_(non-linearity)=0.004).Conclusion In men undergoing assisted reproductive technology for fertility treatment due to non-male factors,age greater than 30 years is significantly associated with a decrease in semen volume,sperm progressive motility,and total motility,as well as an increase in sperm density and DFI.