Semen analysis and fertility prognosis in andrological patients

Semen analyses of 529 men who consulted our department due to infertility problems, were related to the time period prior to conception, with factors adversely affecting the fertility of the female partner taken into consideration. The statistical method used was Cox's proportional-hazard model of regression. Untransformed, logarithmically transformed and dichotomized semen analysis variables were included in the calculations. The relationship between the following parameters and the probability of conception was examined: sperm count, sperm motility, progressive sperm motility, morphology and sperm motility remaining 24 h after ejaculation. All variables co-varied with the probability of conception; however, the exact type of relationship could not be determined by regression analyses. Cox's model assumes an exponential relationship. Our data suggest that this assumption is not suitable for fertility investigations. Using conventionally defined limiting values for normal and pathological semen quality, statistical analysis yielded significant differences in fertility between both categories for all of the variables considered; in the stepwise regression analysis, however, it could be shown that progressive motility and morphology alone were sufficient to discriminate between normal and pathological semen quality. The results are interpreted as indicating that, as a result of semen analysis, it is possible to predict the individual probability of conception if the exact shape of the relationship can be determined, which, up to now, has not been accomplished.     

Feasibility of surveillance of changes in human fertility and semen quality

To show that male fertility is declining is not simple. Few men volunteer and recruitment bias may lead to over-representation of the subfertile. Semen analysis has errors arising from counting and poorly standardized criteria, which may be overcome by automation. Time to pregnancy (TTP)–the number of menstrual cycles taken to conceive–measures fertility and allows male recruitment bias to be estimated. We review automated measurement of sperm concentration, motility and morphology and present a preliminary report on a study to assess a retrospective TTP questionnaire, recruitment bias and feasibility for large-scale surveillance of fertility.     

Prognostic Value of Semen Analyses in infertility Evaluation (Male fertility/Life-table analysis): Der prognostische Wert der Sperma-Analyse bei der Infertilitäts-Bewertung

The aim of the present study was to evaluate which of the various parameters of semen analysis that are most significantly related to the obtainment of pregnancy. A follow up questionnaire was sent to 1953 couples, who had been examined for infertility, and 1,480 (76%) replied. We focused on 713 of these couples, in whom the female partner had a normal fertility set-up (potentially fertile). This study suggests that sperm vitality and sperm concentration bear the most significant relation to pregnancy. Evaluation of a couple's fertility potential by means of the life-table method shows a gradual increase in the pregnancy rate of all couples, irrespective of semen quality, during a observation period of 10 years. The pregnancy rate after 5 years was 14% in a group with reduced semen quality and 44% in a group with normal semen quality.     

Why should we screen for male fertility?

An increasing number of studies show declining sperm counts; however, semen analyses are uncommon until the evaluation for infertility. Semen analysis is a safe, reliable and relatively inexpensive screening test, assessing male fertility and directing further work-up. In young men, the use of semen analysis may identify disease prior to attempted conception and result in improved fertility potential when combined with lifestyle changes, medical or surgical therapy. Furthermore, if sperm counts are significantly low, evaluation and management for genetic causes can be initiated. Our commentary outlines why screening for male infertility in young adult men may be beneficial. We discuss options for early intervention, including sperm cryopreservation, if defects in sperm parameters are identified.     

广东某市农村地区正常生育力男性精液参数的研究

目的探索现阶段正常生育力的健康男性精液的各项参数及其相互关系。方法采用WHO最新推荐的方法,对广东某市农村312例具有生育力的健康志愿者进行精液检测分析。结果(1)具有(a+b)级活动力精子率(60.63±11.76)%;(2)精子存活率(80.89±10.49)%;(3)精子密度(60.09±30.25)×106/ml;(4)不同年龄组间(a+b)级活动力精子、精子存活率及精子密度的参数比较,无显著差异(P>0.05);(5)禁欲时间与(a+b)级活动力精子、精子存活率间的关系呈负相关(P<0.05),与精子密度间的关系呈正相关(P<0.01),但不同禁欲时间组间与(a+b)级活动力精子、精子存活率及精子密度的比较,无显著差异(P>0.05);(6)精子密度与(a+b)级活动力精子和精子存活率无明显的相关关系(P>0.05),且(a+b)级活动力精子和精子存活率始终保持着平衡状态,并在50%以上。结论(1)(a+b)级活动力精子>50%、精子存活率>50%,即使精子密度偏低或<20×106/ml仍不影响正常男性的生育能力;(2)(a+b)级活动力精子、精子存活率以及精子密度与年龄(20~45岁)无关;(3)精子密度的高低对(a+b)级活动力精子和精子存活率无明显影响。     

Semen Characteristics of 49 Fertile Males

We examined the semen characteristics of 49 men whose partners had conceived within the last 16 weeks. There was considerable variation in the semen results. The % of morphologically ideal forms and the absence of sperm bound antibodies appeared to be the two most important semen characteristics when assessing the fertilising potential of the samples. A large proportion of samples (70%) when compared to the WHO standards of normality, were classed abnormal, however, only 25% of the samples had greater than 2 abnormal characteristics. It is diagnostically more relevant to determine the number of abnormalities within a sample rather than categorising the sample as "normal" or "abnormal".     

Resazurin reduction and other tests of semen quality and fertility of bulls

Aim: This study was undertaken to compare the reduction in color of two dyes methylene blue (MBRT) anddye (RRT) with other tests of bull semen quality and to examine their relationship to fertility. Methods: One hundredsixty-four ejaculates from 59 bulls were examined, processed, fertility, and semen from these bulls averaged     

Semen analysis and external quality control schemes for semen analysis need global standardization

One semen analysis laboratory [the Institute of Reproductive Medicine (IRM), Münster, Germany] was enrolled in three external quality assurance programmes in Europe (United Kingdom External Quality Assurance Scheme, European Academy of Andrology, European Society of Human Reproduction) that control for the assessment of sperm concentration, sperm motility and sperm morphology. Agreement between the participating laboratory and the sperm concentrations designated by all three programmes was good. Disagreement between two quality control (QC) programmes providing motility assessment was particularly noticeable in the distinction between motility grades a and b. For the identification of normal sperm morphology, marked differences between the standards set by different QC programmes were apparent. One programme was stricter in its categorization of normal forms, such that an overestimation of normal forms was diagnosed at IRM, whereas agreement with the other programmes was achieved. Variation of results from technicians in the IRM internal QC programme was <13%. The discrepancies between external quality control (EQC) centres demonstrated here are challenging problems to be overcome partly by the andrology laboratories and partly by the providers of EQC services. The introduction of objective, computer-aided sperm assessment in providing designated values may help to rectify this situation. Until this is achieved, EQC programmes should develop an internal programme to monitor their materials and methods for assessment.     

精液分析的培训及效果评估

目的:初步探索建立新技术人员精液分析标准化培训及效果评估方法,为国内男科学实验室室内质量控制和培训提供参考。方法:在本实验室根据《世界卫生组织人类精液检查与处理实验室手册》第5版推荐标准化精液分析方法对新技术人员进行培训,应用统计学分析的方法对精子浓度和活动率考核结果进行评价。结果:新技术人员按照本实验室建立的理论及实践培训方法培训后,分析高、中、低精子浓度样本的变异系数分别为7.72%、3.38%和4.49%;分析高、中、低精子活动率样本的变异系数分别为7.82%、8.09%和6.62%。Bland-Altman分析,与熟练技术人员比较,新技术人员精子浓度检测有4.77%的点在95%的一致性界限以外,在一致性界限范围内,与熟练技术人员检测结果比较,差值的绝对值最大为8×106/ml;活动率分析中7.15%个点在95%一致性界限以外,在一致性界限范围内,差值的绝对值最大为10%。双因素方差分析,两技术人员精子浓度及活动率差异,差异均不显著(P>0.05)。结论:经过培训,新技术人员精液分析结果精确度较好,与熟练技术人员比较,检测结果有较好的一致性,差异不显著。培训达到预期目标,所建立的考核及评估方法对评价培训效果切实可行。     

男性生育力与精液参数的变化趋势

近年来,男性生育力与精液参数的变化趋势不仅是学术界争论的焦点,也是公众舆论关注的热点。尽管评价男性生育力的"金标准"是配偶妊娠,但是临床与科研工作中常常使用精液参数检测作为男性生育力评估的替代指标和间接证据。目前,国内所使用的正常人群精液参数参考值范围均是WHO从国外人群获得的数据,缺乏中国正常人群的精液参数参考值。国内外对于精液参数变化趋势的研究结果表明,世界范围内精液质量总的变化趋势没有明确结论,但部分地区的精液质量下降已经被许多学者所接受。需要进行长期连续性前瞻性研究对精液质量变化趋势作出评估与预测。     

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。     

512例供精志愿者初次精液筛查结果分析

目的 :了解供精志愿者的精液质量状况。　方法 :用WHO推荐的标准化方法和计算机辅助精子分析(CASA)系统检查 5 12例供精志愿者首次精液样本的参数。　结果 :4 8% (2 4 6例 )具有潜在的生育能力 ,但其中只有2 8.5 % (14 6例 )达到卫生部供精质量标准 ,高达 5 2 % (2 6 6例 )未达到WHO的正常人参考值水平。　结论 :对未达到供精质量标准的志愿者 ,做纵向的精液分析追踪能提高精液合格率。供精人群的精液质量状况提示关注男性生殖健康是必要的。     

Clinical significance of the low normal sperm morphology value as proposed in the fifth edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen

The very low cut-off value for sperm morphology of 4% morphologically normal spermatozoa, as proposed in the new edition of the World Health Organization （WHO） manual on semen analysis, is in agreement with recently published values and reflects the trend of a decline in reported mean values for normal sperm morphology. The reduced value for morphologically normal spermatozoa over the years may be due to several factors. The first is the introduction of strict criteria for the evaluation of sperm morphology. Other reasons may include the introduction of additional criteria for sperm morphology abnormalities and the suggested decrease in semen parameters because of increasing negative environmental influences. Although on its own the newly proposed very low normal value may not provide the strong predictive value for a males＇ fertility potential, as originally reported for sperm morphology evaluated according to strict criteria, a good predictive value can still be obtained if the holistic, strict approach for sperm morphology evaluation is followed together with additional sperm morphology parameters now available, because certain morphology patterns and sperm abnormalities are now known to be of strong prognostic value. In addition, better international standardization of the technical methodology, consensus on the interpretation of sperm morphology evaluation criteria and standardized international external quality control （EQC） schemes, are of utmost importance to maintain the good predictive value of sperm morphology.     

Semen quality and infertility status can be identified through measures of oxidation–reduction potential

Standard analyses for evaluating semen quality require technical expertise and are interpretive in nature. Oxidative stress (OS) alters many of the semen parameters; thus, a measure of OS could be an indicator of semen quality. Static oxidation‐reduction potential (sORP) is a universal measure of OS traditionally used in environmental applications but is increasingly used in biomedical studies. sORP was measured to determine how well it associates with semen quality and if it differentiates semen from infertile patients and fertile donors. All study participants (Infertile, n = 365 and Fertile, n = 50) underwent standard semen analyses, and sORP was measured in unprocessed semen. In infertile patients, sORP increased with decreased total sperm number, motility and morphology. sORP values were higher in samples with abnormal quality (low number, motility and/or normal morphology) compared with those of normal quality. Infertile patients had higher sOPR values compared to fertile donors. A sORP cut‐off value of 1.38 mV/10⁶ sperm/ml can differentiate normal from abnormal semen samples, while a cut‐off value of 1.41 mV/10⁶ sperm/ml, can differentiate between infertile and fertile semen samples. In conclusion, sORP provides a quick and unbiased indicator of semen quality that can be a beneficial addition to semen analysis to determine semen quality and fertility status.     

Semen quality evaluation in a cohort of 28213 adult males from Sichuan area of south‐west China

The trends in semen quality are conflicting. Although many previous surveys on semen quality indicated a decline, the trends in semen quality in Sichuan area of south‐west China are not clear. We analysed the semen parameters in a cohort of 28 213 adult males close to general population in Sichuan between July 2007 and June 2012, and investigated the changes on semen quality. The semen parameters including pH, volume, concentration, motility, morphology were measured according to the World Health Organization (WHO) criteria. Kruskal–Wallis analysis of variance was used to examine the statistical differences of semen quality between groups. We found that the medians (5th and 95th percentiles) were 2.4 ml (1.0–5.0) for semen volume, 62.0 × 10⁶ ml^?1 (15.0–142.0) for semen concentration, 39% (18–60%) for sperm progressive motility and 10.5% (1.0–34.5%) for normal morphology. In these 5 years, sperm concentration and the percentage of sperm normal morphology were decreased from 66.0 × 10⁶ ml^?1 to 49.0 × 10⁶ ml^?1 and from 13.5% to 4.5%, respectively; among different reproductive history groups, sperm concentration and the percentage of sperm normal morphology were also decreased in these 5 years. And the incidence of azoospermia was increasing. These may imply that there is a decline in semen quality of adult males in Sichuan area.     

Semen quality and sedentary work position

Increased scrotal temperature can, in experimental settings, markedly disturb the production of semen. Sedentary work position may increase the temperature of the scrotum, but previous studies have failed to determine whether changes in scrotal temperature caused by sedentary work actually do affect semen quality. This study was carried out to elucidate the possible harmful effects of sedentary work on sperm count and other semen characteristics. In 1981-1983 a semen sample was obtained from 3119 men who attended an infertility workup in one of four Danish fertility centres. A total of 2517 men returned a postal questionnaire with information on life style, leisure time activities, occupational history and job duties. Information on job specific work position was obtained from The Danish Work Environment Cohort study 1990 (DWECS). In this analysis DWECS data for a total of 1747 men was included from men aged 18-39 years with >30 h of work per week. For all job titles represented in the DWECS, the mean proportion of sedentary work was estimated. The sperm cell concentration was 30.6 million/mL among men in the quintile with lowest job specific sedentary work compared with 40.5 million/mL in the highest quintile. The difference was, however, not statistically significant. Stratification on infertility period, educational level of the man, fertility centre, and fertility-related disease of the spouse did not influence the results. The analyses do not suggest that sedentary work is a risk factor for abnormal semen characteristics.     

Semen analysis in 21st century medicine： the need for sperm function testing

Sperm function testing, once commonly performed for the infertile couple before employing assisted reproductive technology （ART）, has fallen out of favour in many reproductive medicine centers throughout the world. Indeed, the most recent addition of the ＇World Health Organisation （WHO） Laboratory Manual for the Examination and Processing of Hu- man Semen＇ now groups many of these procedures into a section termed Research Procedures. In large part, this reflects the current clinical practice of bypassing the in-depth evaluation of the male partner, while assuming that if a spermatozoon can be found for intracytoplasmic sperm injection （ICSI）, it must be a healthy cell capable of achieving fertilization. Never- theless, sperm function testing can provide valuable clinical insights into defects causing male infertility. Admittedly, in some cases, functional sperm deficiencies can be overcome using an ART. In other cases, couples will be empowered by the knowledge of the cause of their infertility, and for some couples, perhaps even the likelihood of ICSI success （relative to the spermatozoa）. The knowledge allows them to make truly informed reproductive decisions, including （perhaps） the de- cision to seek donor insemination, to adopt or to remain childless. Knowledge of the cause of their infertility may provide closure for couples and a sense of confidence regarding their choice of reproductive treatment.     

Regression Toward the Mean in Fertility Research — An Empirical Study of Semen Quality

Regression toward the mean denotes circumstances, where extreme observations tend to normalize at repetition. The phenomenon is caused by random variation and may occur whenever mainly persons with extreme values are subject to repeated examinations. We furnish empirical evidence that the phenomenon may be quantitatively important in fertility research with regard to some, but probably not all indicators of semen quality.     

The HOS test and its relationship to fertility in the stallion

The hypo-osmotic test has been used successfully on equine semen and was considered to be a simple and accessible method which could be a useful addition to routine equine semen analysis. It was therefore of interest to determine whether the hypo-osmotic test is significantly correlated to proposed criteria of fertility. The stallions were divided into two groups on the basis of threshold levels of fertility. A significant difference (P<0.05) was found between the two groups for the following parameters: progressive motility, morphologically normal spermatozoa, percentage of swelling with the hypo-osmotic test, percentage of pregnant mares and number of services per pregnancy. The hypo-osmotic test provided a simple evaluation of membrane function and the results obtained show stallions with low swelling scores (<40%) to be of doubtful fertility. The hypo-osmotic test was not correlated with percentage of pregnant mares but showed a tendency to correlate with the number of services per pregnancy, therefore it could be an additional method for evaluating stallion fertility. Further studies are needed to confirm this observation.