精液参数与射精频率的关系

通过对２０名性功能正常的男子（１０例精液正常，１０例少弱精症）连续１周，每天采集精液标本进行观察，探讨了他们的精液参数与射精频率之间的关系。结果表明，正常组的精液容积、１次射精的精子总数逐日下降，于第５天降至原水平５０％左右，以后维持在该水平上下波动，而精子密度并不下降；少弱精组精液容积、精子密度及１次射精的精子总数均显著下降。精子活力和形态在两组中都相对变化不大。     

Cross-sectional study of semen parameters in a large group of normal Chinese men

Testicular size, semen characteristics and serum reproductive hormone levels were studied in 1239 normal Chinese men. The mean testicular size of 17 ml in this group of subjects was similar to other reports in Orientals but was smaller than that reported in Caucasians. Semen volume, and the sperm count, motility and morphology were comparable to those described for Caucasian subjects. The cervical mucus penetration test (Kremer's test) and the zona-free hamster egg penetration test were also studied in some of the subjects. Age showed a positive correlation with the serum levels of FSH and LH, which were highly correlated with each other. Sperm concentration and the total sperm count were positively correlated with testicular volume, the length of abstinence, the % of sperm with an oval head, and the zona-free hamster egg penetration test, but were negatively correlated with serum FSH. Sperm motility was negatively correlated with the duration of abstinence but was positively correlated with the % normal sperm. The results constitute a normal data base from Chinese men for comparison with studies in male infertility and fertility regulation.     

Study of a group of 484 fertile men Part II: Relation between age (20–59) and semen characteristics

Commonly measured semen variables as well as post-thaw motility have been studied as a function of age in fertile men. The mean age was 34.6 (so = 6.6). No significant change with age was found for the sperm count, semen volume or total number of spermatozoa. Conversely, there were significant differences between age groups for the percentage of normal cells ( P < 0.01) and the percentage of motile forms ( P < 0.01) as well as for the after-thaw motility ( P < 0.001). These three variables rise, reach a maximum level at 30 to 35 years of age and then decrease. These changes are not explained by variations in the length of abstinence.     

Semen quality changes among 2343 healthy Slovenian men included in an IVF-ET programme from 1983 to 1996

To determine whether semen quality in Slovenians has changed over 14 years (1983-96), we analysed retrospectively the semen of 2343 healthy men with a normal spermiogram, who were partners of women with tubal infertility included in the IVF-ET programme. Age at semen collection, duration of sexual abstinence, semen volume, sperm concentration, total sperm count, percentage of spermatozoa with progressive motility, and normal morphology were determined. Multiple regression analysis was used to assess the changes in sperm characteristics according to the year of semen collection, year of the man's birth and the duration of sexual abstinence. Semen volume, sperm concentration, sperm count and total sperm motility did not change between 1983 and 1996, whereas between 1988 and 1996 rapid progressive sperm motility decreased by 0.95% per year (p < 0.0001). Semen volume, sperm concentration, and sperm count increased with duration of sexual abstinence. After adjustment for the year of semen collection and duration of sexual abstinence, multiple regression analysis showed that sperm concentration decreased by 0.67% per each successive year of birth (p = 0.03). Thus the sperm concentration decreased from 87.6 x 10(6)/mL in men born in the 1940s to 77.3 x 10(6)/mL in those born between 1956 and 1960. After 1960, sperm concentration was found to increase. In 2343 healthy men, no decline in semen quality, except in rapid progressive motility, was observed in the study period. Lower sperm concentration was found among men born between 1950 and 1960. This could be related to worse socio-economic status, stress or negative environmental factors in this time period.     

上海地区正常生育力男性精液参考值初探

目的:回顾分析上海地区志愿捐精者与正常生育力男性精液分析各项主要参数的分布特征,比较两组男性精液质量的差别,探讨上海地区男性精液参数的正常参考值下限。方法:2010年10月至2011年7月上海市人类精子库招募正常生育力男性41例,健康捐精者100例,按《世界卫生组织人类精液检查与处理实验室手册》(第5版)进行精液常规检测,评估精液体积、精子浓度、前向运动(PR)精子百分率、精子总数和PR精子总数的均值,标准差,并进行t检验。同时统计正常生育力组上述各参数的分布,得出精液特征参数的正常参考值下限。结果:健康捐精组与正常生育力组精液常规各项主要参数(精液体积、精子浓度、PR精子百分率、精子总数、PR精子总数)间差异无统计学意义(P<0.05)。上海地区正常生育力男性精液参考值下限(P<0.05)为:浓度≥27.3×106/ml、PR≥8.1%、体积≥0.82 ml、精子总数≥44.73×106/1次射精、PR精子总数≥24.68×106/1次射精。结论:在评估男性生育力时,精子总数和PR精子总数可能是比精子浓度、精液体积和PR精子百分数更具参考价值的评价指标。     

Evaluation of reference values of standard semen parameters in fertile Egyptian men

The reference values of human semen, published in the WHO's latest edition in 2010, were lower than those previously reported. The objective of this study was to evaluate reference values of standard semen parameters in fertile Egyptian men. This cross‐sectional study included 240 fertile men. Men were considered fertile when their wives had recent spontaneous pregnancies with time to pregnancy (TTP) ≤12 months. The mean age of fertile men was 33.8 ± 0.5 years (range 20–55 years). The 5th percentiles (95% confidence interval) of macroscopic semen parameters were 1.5 ml for volume and 7.2 for pH. The 5th percentiles of microscopic parameters were 15 million/ml for sperm concentration, 30 million per ejaculate for total sperm count, 50% for total motility, 40% for progressive motility, 62% for vitality, 4% for normal sperm forms and 0.1 million/ml for seminal leucocyte counts. In conclusion , fertile Egyptian men had higher reference values of sperm total motility, progressive motility and vitality, and lower reference values for total sperm counts as compared to those determined by the latest edition of the WHO laboratory manual in 2010. Other semen parameters were identical to those defined by the WHO 2010 manual.     

Within-subject variation of seminal parameters in men with infertile marriages

As little information exists on the semen variability in infertile men, this study aimed at analysing the within-subject variability of semen from men with infertile marriages included in an intrauterine insemination (IUI) programme. Five ejaculates from each of 436 men (2180 specimens) were analysed. The within-subject coefficients of variation (CV(w)) were high for all parameters (semen volume, sperm concentration, forward motility and combined parameters), ranging from 0.73 for the total motile sperm count to 0.27 for the semen volume. Nevertheless, within-subject fluctuations were smaller than the between-subject variability, as indicated by high Intraclass Correlation Coefficient (ICC) values, which, however, significantly lowered when 相似文献   

Relationship between age and semen parameters in men with normal sperm concentration: analysis of 6022 semen samples

This study evaluates retrospectively the relationship between age and semen parameters among men with normal sperm concentration. It was based on computerized data and performed in an Academic Fertility and IVF Unit. Six thousand and twenty-two semen samples with sperm concentrations of >or=20 x 10(6) ml(-1) were examined according to WHO criteria and analysed in relation to patients' age. For each age group, mean values +/- SD of semen volume, sperm concentration, percentage of motile spermatozoa, normal morphology, acrosome index, total sperm count/ejaculate, total motile sperm count/ejaculate and sexual abstinence duration were examined. A peak semen volume of 3.51 +/- 1.76 ml(-1) was observed at age >or=30 to <35 years and a lowest volume of 2.21 +/- 1.23 ml(-1) was observed at age >or=55 years (P<0.05). Sperm motility was found to be inversely related to age with peak motility of 44.39 +/- 20.69% at age <25 years and lowest motility of 24.76 +/- 18.27% at age >or=55 years (P<0.05). A reduction of 54% was observed for total motile sperm, between values of 103.34 +/- 107 x 10(6) at age >or=30 to <35 years and 46.68 +/- 53.73 x 10(6) (P<0.05) at age >55 years. A statistically significant and inverse relationship was observed between semen volume, sperm quality and patient age, in spite of prolonged sexual abstinence duration. Top sperm parameters were observed at age >or=30 to <35 years, while the most significant reduction in sperm parameters occurred after the age of 55 years.     

Seminal factor VII and factor VIIa: supporting evidence for the presence of an active tissue factor-dependent coagulation pathway in human semen

Human semen spontaneously coagulates into a semisolid mass and then wholly liquefies in a process that may have some similarity to that of normal blood. This well described phenomenon is referred to as coagulation and liquefaction of semen. Besides other active components of the haemostatic system, semen contains a significant amount of functional tissue factor (TF). However, TF needs factor (F)VII in order to exert it actions. In this study, we assessed human semen for the presence of FVII and FVIIa, and related their levels to conventional fertility parameters. Using a functional, one stage, clotting assay based upon the prolongation of the prothrombin clotting time, using the ACL 300R analyser and an Imubind FVIIa ELISA assay, FVII and FVIIa levels were measured in 97 semen specimens obtained from sub-fertile (sperm counts <20 x 10(6)/mL), normally fertile (sperm counts >or=20 x 10(6) but <60 x 10(6)/mL), fertile sperm donors (sperm counts >or=60 x 10(6)/mL), vasectomized subjects and in a pooled normal semen parameters group (categorization into groups was based on the World Health Organization guidelines on fertility criteria). In addition, conventional semen parameters were analysed on all semen samples. Both FVII and FVIIa were quantifiable in human semen. The mean levels of FVII and FVIIa were 4.4 IU/dL and 12 ng/mL respectively. Despite the observed variations of FVIIa levels in the studied groups they did not meet statistical significance when the groups were tested against each other. However, seminal FVIIa levels showed a significant positive association with semen liquefaction time, sperm motility and semen volume. The anti-sperm antibodies and sperm-agglutination groups were also associated with raised seminal FVIIa levels. We observed no significant relationship between FVIIa levels and total sperm concentration, sperm count per mL (sperm density), sperm progression and days of sexual abstinence. This study demonstrates that human semen contains appreciable amounts of FVII and FVIIa. It is possible to quantify these using commercially available assays. There also appears to be a direct correlation between the levels of these factors and certain seminal parameters. This finding reinforces the concept of an active clotting system in human semen, by establishing the missing link in the activation of a TF-dependent pathway.     

1985～2008年间我国正常男性精液质量变化分析

目的:研究1985～2008年间国内正常男性精液质量变化趋势。方法:检索历年发表的精子质量方面的文献,系统收集相关资料和数据,利用散点图和直线回归法,分析近24年正常男性精液精子密度、精液量及精子总数的变化。结果:1985～2008年间国内正常男性精液质量参数中精液量没有明显变化(P>0.05)。1985～1994年精子密度和精子总数不存在与时间相关的变化(P>0.05),但自1995年后的14年以来,精子密度和精子总数呈现显著下降趋势(P<0.05),精子密度从1995年81.5×106/ml下降到2008年66.7×106/ml,每年降低1.40%;精子总数从1995年257.2×106下降到2008年的185.9×106,每年下降2.15%。结论:1985～1995年间国内正常男性精液质量未见明显变化,而1995～2008年14年间精子密度和精子总数明显降低,很可能与进入重化工时代引起的日益加重的环境污染有关。     

A critical method of evaluating tests for male infertility

Considerable uncertainty surrounds the selection of test values that separate infertile from fertile men in the evaluation of male infertility. We herein describe an objective method of determining these values, referred to as threshold values, for different infertility tests. Using test results from fertile men threshold values were chosen such that 96 per cent of the semen samples from the fertile men were scored as fertile. These threshold values then were used to evaluate 100 semen samples from 74 men presenting for evaluation of infertility. Using this method we constructed infertility profiles on each of the 100 semen samples presented for infertility evaluation and found that the zona pellucida-free hamster egg penetration test (a measure of a spermatozoon's ability to undergo capacitation and penetrate an egg) identified 66 per cent of these samples as infertile, while multiple exposure photomicrography (a quantitative measure of sperm motility) identified 54 per cent of these samples as infertile. This compares with results from routine semen analyses using the same method, which identified none of the samples as infertile by sperm motility grade, 1 per cent by semen pH, 4 per cent by the percentage of motile sperm, 7 per cent by the total count of motile sperm, 10 per cent by the total sperm count, 11 per cent by the semen leukocyte concentration, 12 per cent by the concentration of motile sperm, 13 per cent by ejaculate volume, 16 per cent by sperm concentration and 27 per cent by sperm morphology. This method of analyzing infertility test results provides insight into the potential causes of male infertility and offers a critical approach towards understanding the complex problem of male fertility dysfunction.     

Does exposure to computers affect the routine parameters of semen quality？

Aim： To assess whether exposure to computers harms the semen quality of healthy young men. Methods： A total of 178 subjects were recruited from two maternity and children healthcare centers in Shanghai, 91 with a history of exposure to computers （i.e., exposure for 20 h or more per week in the last 2 years） and 87 persons to act as control （no or little exposure to computers）. Data on the history of exposure to computers and other characteristics were obtained by means of a structured questionnaire interview. Semen samples were collected by masturbation in the place where the semen samples were analyzed. Results： No differences in the distribution of the semen parameters （semen volume, sperm density, percentage of progressive sperm, sperm viability and percentage of normal form sperm） were found between the exposed group and the control group. Exposure to computers was not found to be a risk factor for inferior semen quality after adjusting for potential confounders, including abstinence days, testicle size, occupation, history of exposure to toxic substances. Conclusion： The present study did not find that healthy： men exposed to computers had inferior semen quality. （Asian J Andro12005 Sep; 7： 263-266）     

Comparison of semen quality in older and younger men attending an andrology clinic

The effects of age on semen quality were analysed in patients referred to an andrology outpatient clinic in a retrospective study covering a period of 3 years. Semen analyses of older men (n = 66; > or = 50 years; median: 53) were compared with those of young patients (n = 134; 21-25 years; median 24). The duration of sexual abstinence was longer among older patients (median: 5.5 vs. 5.0 days; + 10%, P < 0.05). Even after adjustment for duration of sexual abstinence, progressive motility (- 27%, P < 0.01), percentage of morphologically normal spermatozoa (- 44%, P < 0.01) and semen volume (- 29%, P < 0.0005) were significantly lower in older than in younger men. Impaired sperm morphology was mainly attributed to abnormal staining of flagella (+ 50%, P < 0.05) and an increased portion of coiled or bent tails (+ 44%, P = 0.001) indicating epididymal dysfunction. Total sperm count and sperm concentration were unaffected by age. Age-dependent changes in accessory gland function, as indicated by fructose concentration (- 27%, P < 0.05), was correlated with lower semen volume. Moreover, serum testosterone levels were significantly reduced in the group of older men (median: 3.0 vs. 3.6 ng ml-1; -17%, P < 0.005).     

Reproductive history and semen analysis in prevasectomy fertile men with and without varicocele

A group of 598 allegedly fertile men requesting vasectomy were investigated; varicocele was found in 97 (16.2%) of these men. The mean ages and age distributions of men with and without varicocele were not significantly different. Reproductive histories (number of pregnancies, living children and spontaneous abortions, as well as incidence of present pregnancy) were similar in both groups. The average seminal characteristics (semen volume, sperm count, total sperm count, percentage of motile spermatozoa, quality of motility, morphology) were not different for men with and without varicocele, except for a slight, but significantly higher incidence of oval-headed sperm in men without varicocele. However, the incidence of varicocele was significantly higher in men with sperm counts below 40 million/ml. Three important observations may be made from this study: 1) the incidence of varicocele in this prevasectomy population was similar to that reported for the general population, but lower than the incidence reported for male partners of infertile couples; 2) in this population of allegedly fertile men, the presence of a varicocele did not significantly affect reproductive performance; 3) even though the incidence of varicocele was higher in men with sperm counts below 40 million/ml, the average seminal characteristics were not different in men with and without varicocele.     

Between and within Subject Correlations and Variances for Certain Semen Characteristics in Fertile Men

Between subject and within subject variances and correlations for different semen characteristics have been determined for a population of 315 fertile men who provided one or more ejaculates within an abstinence period of 1 to 5 days. The semen characteristics measured were sperm count, semen volume, pre-freeze motility and post-thaw motility. An approach via a decomposition of the variance or via a decomposition of correlation leads essentially to the same conclusions i.e. the within subject factors are not negligible but are less important than the between subject ones. Thus there is broad evidence for overall differences in the quality of the ejaculate from one subject to the other but not for different ejaculates of the same subject.     

Aniline blue staining as a marker of sperm chromatin defects associated with different semen characteristics discriminates between proven fertile and suspected infertile men

A retrospective study of 49 men with proven fertility and 396 suspected infertile men was conducted with the primary objective of investigating the relationship between the nuclear maturity of sperm and male fertility. Acidic aniline blue staining was used to detect chromatin defects of sperm nuclei related to their nucleoprotein content as associated with DNA. The discriminant value of the percentage of unstained nuclei (= percentage of mature heads, MH) and of other semen characteristics, was analysed by a stepwise (forward) linear regression model. Semen characteristics that discriminated significantly between the two groups of subjects were, in descending order: (1) the percentage of normal sperm, (2) the percentage of amorphous heads, (3) the percentage of tapered heads, (4) semen volume, and (5) the percentage of MH. The discriminant value of each of the significant characteristics was studied by means of ROC-curves. MH had the best ROC-curve profile; its cut-off value was found to be equal to 70% (74.5 +/- 2.6% for the donor group versus 53.0 +/- 1.1% for the patient group). A simple infertility score (SIS) including MH, was built according to the cut-off values inferred from the ROC-curves. SIS allowed an overall satisfactory separation of the two groups (less than or equal to 4 = fertile, 5-6 = uncertainty zone, greater than 6 = infertile). Our results indicate that the addition of the evaluation of sperm head maturity to routine semen analysis improves the assessment of fertility in men.     

Variation in, and inter-relationship between, prostaglandin levels and other semen parameters in normal men

In each of 135 ejaculates from 46 healthy men, semen volume, various sperm parameters and the level of prostaglandins (PGs) were determined. Data were analysed to determine the within- and between-subject variability, the effect of abstinence period and the correlation between different parameters. Data which did not reveal a Gaussian distribution were transformed logarithmically. For all variables the between-subject variance exceeded the variation within subjects (P less than 0.001). Variation in time of abstinence between 1 and 3 days influenced semen volume and sperm content as well as the content of 19-hydroxylated PGs, but did not affect sperm motility or the concentration of PGE or PGF. A significant negative correlation was found between the seminal content of PGE and PGF and the total sperm count as well as the sperm concentration. Sperm motility was related to the balance between the content of 19-hydroxy PGE and 19-hydroxy PGF but not to their separate concentrations. The ratio between 19-hydroxy PGE and 19-hydroxy PGF did not change when the time of abstinence differed. Synthesis of the two 19-hydroxylated PGs seemed to be regulated by the same mechanism, but their hydroxylation capacity still varied considerably between individuals.     

Time-related decline in sperm motility patterns in men with cytotoxic antibodies

Sperm motility patterns in semen from 10 fertile nonautoimmune men (fertile control group) and 33 infertile men with various titers of cytotoxic sperm antibodies in their seminal plasma (group 1: titers less than or equal to 16, n = 6; group 2: titers 64 to 512, n = 12; group 3: titers greater than or equal to 1024, n = 15) were evaluated every 2 hours for 12 hours and finally at 24 hours. A significant decline in sperm swimming speed and linearity was observed at 6 hours in semen from 27 infertile men with sperm antibodies. Beginning at 8 hours, semen from sperm antibody-positive men in group 2 showed a significant decline in percentage motile sperm (p less than 0.001) compared to the fertile controls. The percentage motility in semen of donors in groups 1 and 3 was significantly lower than that in semen of fertile donors at 10 hours (p less than 0.05), 12 hours (p less than 0.01), and 24 hours (p less than 0.001). The mean velocity in groups 2 and 3 was significantly less than that in fertile controls at 10 and 12 hours (p less than 0.05). The linearity of sperm motility started to decline 4 hours after semen samples were obtained from sperm antibody-positive groups 2 and 3 in contrast to sperm antibody-negative fertile or infertile groups (p less than 0.05). It is concluded that the presence of cytotoxic sperm antibodies in the seminal plasma adversely affects sperm linearity as early as 4 hours after semen collection.(ABSTRACT TRUNCATED AT 250 WORDS)     

CSRM数据报告:2008～2018年中国健康男性精液质量变化分析

目的探讨近10年中国健康男性精液质量的变化情况。方法中华医学会生殖医学分会(CSRM)收集2008~2018年向中国七家精子库8 989位捐精者基本情况及精液参数,按照WHO《人类精液检查与处理实验室手册》标准分析精液体积、精子浓度、前向运动百分率和正常形态率等参数。资料分析方法采用ANOVA分析、偏相关分析、线性回归分析等。结果研究对象总样本量为8 989人,平均年龄为(26.26±5.35)岁。2008~2018年间,精液体积、精子浓度、精子总数、总活力百分率、前向运动精子百分率、精子正常形态率各参数均值有统计学差异(P<0.001);偏相关分析控制年龄、BMI因素,结果显示精液体积、精子总数、前向运动百分率、精子正常形态率均与时间呈负性相关,系数分别为-0.177、-0.135、-0.104、-0.084(P<0.001)。线性回归分析显示精液体积、精子总数、前向运动精子百分率、精子正常形态率变化与时间相关,均呈下降趋势(β=-0.148、-9.988、-0.134、-0.695;P<0.001)。结论 2008~2018年间,中国健康男性精液质量随时间变化呈下降趋势。     

男性年龄与精子顶体酶活性及精子DNA碎片指数的相关性分析

目的探讨男性年龄与精子顶体酶活性、精子DNA碎片指数(DFI)的相关性。方法选取2016年1~8月在我院生殖医学中心就诊的436例不育症男性患者为研究对象,所有患者均行精液常规检查、精子顶体酶活性检查和(或)精子DFI分析。将患者按年龄分为<30岁、30~39岁、≥40岁3组,分析各组的精液常规、顶体酶活性及精子核DFI的差异及其相关性。结果不同年龄段患者的体重指数(BMI)、禁欲天数、精液量无显著性差异(P>0.05);年龄≥40岁组患者的前向运动精子百分率、活动精子百分率及精子顶体酶活性显著低于<30岁和30~39岁组(P<0.05);≥40岁组患者的精子DFI显著高于<30岁和30~39岁组(P<0.05)。年龄与前向运动精子百分率及活动精子百分率之间呈负相关(P<0.05),但是相关性较弱。精子顶体酶活性与精子正常形态率、前向运动精子百分率、非前向运动精子百分率、活动精子百分率呈正相关(P<0.05);精子DFI与年龄、禁欲天数、前向运动精子百分率呈正相关(P<0.01),与精液量、精子浓度、活动精子百分率呈负相关(P<0.05);精子顶体酶活性和DFI之间无相关性(P>0.05)。结论年龄增长会导致精液前向运动精子百分率、活动精子百分率、精子顶体酶活性、DFI等参数改变,直接或间接影响男性生育力。说明年龄对男性不育的影响是多方面的,建议有生育需求的大龄(≥40岁)男性尽早进行生育咨询与评估。