Effect of male occupational heat exposure on time to pregnancy

The relationship between male occupational heat exposure and the time required to achieve a pregnancy [TTP] was studied in a retrospective survey of 402 fertile couples. The TTP for t he subgroups 'exposure t o heat' (median = 4 .0 months; mean 11.8; SD = 13.3) and 'professional driver >3 h/day' (median = 4.5; mean = 14.4; SD = 28.5) was significantly longer (both p < 0.05) than for the controls (median = 2.8; mean = 7.8; SD = 13.3). Bakers and welders showed comparable results: only 14% of the bakers' partners became pregnant within 3 months (cf. 55% of controls, p < 0.05) and only 29% became pregnant within 6 months (cf. 74% of controls, p < 0.02). This study suggests that occupational exposure to heat is a 'weak' risk factor for male subfertility.     

Sperm chromatin integrity may predict future fertility for unexplained recurrent spontaneous abortion patients

The pathogenesis of recurrent spontaneous abortion (RSA) is multi-factorial, complex and poorly understood. In the present study, semen parameters, including sperm chromatin integrity, sperm concentration, sperm motility and sperm morphology, were compared between 111 men whose partners had a history of unexplained RSA (RSA group) and 30 healthy fertile men (control group). The RSA group was further separated into three subgroups, depending on their reproductive outcome during the 12?months after they were enrolled in the study: the pregnancy subgroup consisted of 43 men whose partners achieved a successful pregnancy up to at least the 24th week of gestation; the abortion subgroup included 31 men whose partners experienced further abortions; and the infertile subgroup had 37 men whose partners did not have any positive pregnancy test after regular, unprotected intercourse. Significantly lower proportion of sperm with normal morphology was found in the abortion subgroup (14.7?±?4.3%) than in the control group (17.5?±?5.0%). Sperm concentrations were significantly lower in the infertile subgroup (55.7?± 24.1%) than in the controls (68.6?±?27.8%). The rates of abnormal sperm chromatin integrity were significantly higher in the abortion (16.7?±?7.7%) and infertile (16.3?±?6.6%) subgroups, compared to the control group (13.0?± 4.4%). Logistic regression analysis showed that the subsequent reproductive outcome of the 111 RSA patients was negatively correlated to the rates of abnormal sperm chromatin integrity. In conclusion, sperm chromatin integrity, sperm morphology, and sperm concentration were associated with future reproductive outcome of RSA patients. The sperm chromatin integrity was a significant predictor for future abortion and infertility.     

Stepwise regression analysis to study male and female factors impacting on pregnancy rate in an intrauterine insemination programme

The aim of this study was to evaluate the impact of male and female factors on the pregnancy rate in an intrauterine insemination (IUI) programme. Data on 522 cycles were retrospectively studied. All patients 39 years or younger were included in the study where data were available on male and female diagnosis, as well as on ovulation induction methodology. Regression analysis was possible on 495 cycles to study different factors affecting the pregnancy rate per treatment cycle. Logistic regression identified variables which were related to outcome and were subsequently incorporated into a statistical model. The number of follicles was found to have a linear association with the risk ratio (chance) of pregnancy. The age of the woman was also found to have a linear (negative) association with pregnancy. The percentage motility and percentage normal morphology (by strict criteria) of spermatozoa in the fresh ejaculate were the male factors that significantly and independently predicted the outcome. Percentage motility > or = 50 was associated with a risk ratio of pregnancy of 2.95 compared to percentage motility < 50. Percentage normal sperm morphology > 14% was associated with a risk ratio of pregnancy of 1.8 compared to percentage normal morphology < or = 14%. Female patients with idiopathic infertility were divided into three groups according to normal sperm morphology. The pregnancy rate per cycle was 2.63% (1/38) for the P (poor) pattern group (0-4% normal forms), 11.4% (17/149) for the G (good) pattern group (5-14%), and 24% (18/75) for the N (normal) pattern group (> 14% normal forms). A female diagnosis of endometriosis or tubal factor impacted negatively on the probability of pregnancy (risk ratio of 0.17), compared with other female diagnoses. Male and female factors contribute to pregnancy outcome, but the clinician can influence prognosis by increasing the number of follicles, especially in severe male factor cases.     

Effect of alcohol intake and cigarette smoking on sperm parameters and pregnancy

Much has been published about smoking and alcohol intake influencing male fertility, sperm parameters and reproductive outcome. However, there is no conclusive agreement about the effects of cigarette smoking and alcohol use on these outcomes and thus no generally accepted guidelines. The combined effect of cigarette smoking and alcohol intake, though, has not been rigorously investigated. Because alcohol consumption and smoking are often seen together, this study focuses on the effect of smoking and drinking habits separately and combined on semen parameters, such as volume, sperm count, motility and morphology, and on pregnancy outcome. These suggested toxic effects are studied in a group of subfertile, asthenozoospermic men (<10% motile spermatozoa), compared with a group of ‘proven fertile’, healthy men. The extreme asthenozoospermic group has especially been chosen because of the suspected effect, that is, oxidative stress, on sperm motility. In our study, we found that cigarette smoking and alcohol intake did not differ between the subfertile and fertile group. In conclusion, cigarette smoking and alcohol consumption do not appear to significantly affect sperm parameters, such as volume, sperm count, motility and morphology or pregnancy outcome in our study population.     

How work-place conditions,environmental toxicants and lifestyle affect male reproductive function

Major temporal and geographical shifts in male reproductive function is presently an issue worldwide. The hormonal disruption hypothesis has achieved considerable attention but epidemiological evidence in support of the theory is lacking. Several occupational hazards to male reproductive function are known but exposure prevalences are hardly sufficient to play a role for reduced sperm count in the general male population. Sedentary work may be an exception. Perhaps prolonged time in the sedentary position exhausts the testicular heat regulation. But so far studies addressing implications of the heat hypothesis in the general population are few. Neither change of sexual behaviour nor reduced period of sexual continence seems to be a likely explanation. Tobacco smoking and consumption of caffeine and alcoholic beverages in adulthood have a rather marginal impact on spermatogenesis and can hardly explain major shifts or regional differences in male reproductive health. However, prenatal effects following smoking during pregnancy might play a role because we have witnessed a smoking epidemic among fertile women in some countries during the second half of the twentieth century. Moreover, if genetic factors play more than a marginal role for testicular function and sperm count, pregnancy planning resulting in reduced family size during the past 100 years could possibly explain a decline in semen quality because the most fertile part of the population reproduce less while the subfertile probably continue to get a limited number of children.     

中国男性十一酸睾酮酯注射避孕有效性多中心研究

目的评估十一酸睾酮酯（TU）注射避孕的安全性、有效性、可复性和可接受性。方法1,045名健康的有生育力的中国男性,每月一次TU500mg肌注共30个月,统计分析其配偶的妊娠率、精液参数、睾丸体积、生殖激素水平及安全性评估。结果在6个月的抑制期内有43名对象（4．8％）未达到无精子或严重少精子症;855名对象进入起效期,其中733名完成每月一次TU注射和恢复阶段。在避孕有效期的24个月,暴露1,554／人年中有9次妊娠,累计避孕失败率为1．1／100人;综合失败率6．1％,其中包括1．3％抑制不充分和4．8％短暂抑制后的精子反跳。本研究无严重不良事件报告。除了2名对象以外全部恢复生精功能,达到正常有生育力参考值范围。结论每月一次TU500mg肌注可以为健康有生育力的中国男性提供安全、有效、可逆的避孕。     

精子MTCYB基因缺失与男性不育的关系

目的 探讨精子ＭＴＣＹＢ基因缺失与男性不育的关系。方法 应用ＰＣＲ技术对１００例不育男性（精子活动力差５０例,精子活动力正常５０例）,和３０例已育男性的精子ＭＴＣＹＢ基因进行检测。结果 男性不育组精子ＭＴＣＹＢ基因缺失率为１６％,其中精子活力差的５０例标本检出９例,精子活动力正常的５０例标本中检出７例,经统计学检验二组差异无显著性。     

Effect of abamectin exposure on semen parameters indicative of reduced sperm maturity: a study on farmworkers in Antalya (Turkey)

Environmental exposure to pesticides may cause serious health risks including fertility and reproductive function. The aim of this study was to highlight whether there is a relationship between exposure to abamectin and male fertility parameters of farmworkers. Twenty male farmworkers who were using abamectin and 20 men not exposed to pesticides were recruited as experimental and control groups, respectively. Semen analysis, molecular markers of sperm maturity and serum reproductive hormone levels were evaluated. In experimental group, high plasma abamectin levels were detected. These men have decreased sperm motility. Moreover, diminished molecular markers of sperm maturity, such as decreased hyaluronic acid (HA) binding of sperm, increased numbers of aniline blue positive sperm and increased percentage of creatine kinase (CK) positive sperm, were observed in abamectin‐exposed men. Their serum testosterone, LH and FSH levels did not change significantly. We conclude that exposure to abamectin may impair male fertility by effecting semen quality.     

Correlation between male age, WHO sperm parameters, DNA fragmentation, chromatin packaging and outcome in assisted reproduction technology

In the human, male ageing results in reproductive hormonal and cellular changes that can influence semen quality (volume, motility, concentration and morphology) and ultimately result in a reduced fertilising capacity and a longer 'time to pregnancy' for ageing men as well as an increased risk for miscarriage. This prospective cohort study of 278 patients undergoing a first in vitro fertilisation or intracytoplasmic sperm injection treatment was undertaken to examine whether patient's age was reflected in sperm motility, concentration, morphology as well as in DNA fragmentation (DFI) and immature chromatin (unprocessed nuclear proteins and/or poorly condensed chromatin) as measured by the sperm chromatin structure assay. This study also investigated the possible influence of male age (after correcting for female age) on their fertilising capacity, on obtaining a pregnancy and a healthy baby at home. Logistic regression analysis did not reveal any male age-related influences on sperm parameters like concentration, motility or morphology. No significant male age-related increase in DFI or immature chromatin was demonstrable for these patients. Elevated male age, after correcting for female age, was not related to lower fertilisation rates or significant decreases in the chance for a healthy baby at home.     

Reassessment of the accuracy of traditional sperm characteristics and adenosine triphosphate (ATP) in estimating the fertilizing potential of human semen in vivo

Receiver operating characteristic curves and accuracy parameters were computed for traditional sperm characteristics (concentration, motility, morphology) and the number of peroxidase negative cells, and the concentration of adenosine triphosphate (ATP) in semen from populations of fertile and infertile men, and men who achieved a pregnancy after varicocele treatment. The percentage and concentration per millilitre of spermatozoa with rapid linear progressive motility, and the ATP concentration, provided the best discrimination between fertile and treated fertile from infertile men. The misclassification rate was higher for sperm morphology, total progressive motility and viability, whereas sperm concentration and the total sperm count per ejaculate had the worst discriminating power. The number of peroxidase negative cells per 100 spermatozoa was highly specific in identifying men who achieved pregnancy after varicocele treatment. The lower limit of normality of sperm characteristics was remarkably different between fertile men and men achieving pregnancy after treatment or during infertility work-up.     

Seminal fibronectin in fertile and infertile males

This study aimed to assess seminal plasma fibronectin in fertile and infertile males. Ninety infertile males were investigated; asthenozoospermia (n = 27), asthenoteratozoospermia (n = 30), oligoasthenoteratozoospermia (n = 33) compared with 20 healthy fertile controls. They were subjected to semen analysis, seminal plasma fibronectin estimation by radial immune diffusion, serum testosterone (T) and follicle stimulating hormone (FSH) estimation by ELISA. There was significant increase of seminal plasma fibronectin among different infertile groups compared with the controls. Significant negative correlation was elicited between seminal fibronectin and sperm count, sperm motility grades A, B, A + B, sperm velocity, linear velocity, linearity index, sperm normal forms and serum T. Seminal fibronectin showed significant positive correlation with grade D sperm motility and serum FSH. ROC curve analysis discriminating controls and other infertile groups demonstrated criteria value of < 674 mg l(-1) (sensitivity 100% and specificity 96.4%). It is concluded that increased seminal fibronectin is associated with decreased sperm count and sperm motility.     

Parental exposure at periconception to environmental adverse factors and early embryo loss in Tianjin, China

<正>Objective:To study the association of environmental adverse factors with early embryo loss,and explore the possible risk factors in daily life. Methods:A questionnaire was administered to 93 new cases of embryo loss(case group) collected in four general hospitals in Tianjin from April 2007 to April 2008 and 93 matched cases of induced abortion(control group) in normal pregnant women who sought the abortion by other reasons.The questionnaire covered information on parental exposure to various environmental factors during and before pregnancy,and the information on daily life.Data were analyzed by single-factor analysis,multiple linear regression and logistic regression analysis.Possible risk factors were identified and odds ratio calculated. Results:Cooking frequently during pregnancy,more daily traffic hours,and decoration history in early pregnancy and paternal exposure to toxic matters three months before pregnancy were associated with early embryo loss, while maternal education was a protective factor. Conclusion:Women exposed to the harmful substances from traffic emissions,cooking and decoration could be at an increased risk of early embryo loss.     

Male accessory gland infection frequency in infertile patients with chronic microbial prostatitis and irritable bowel syndrome

Recently, we reported an increased prevalence of chronic bacterial prostatitis (CBP) in patients with prostatitis syndromes (PS) and irritable bowel syndrome (IBS) compared with patients with PS alone. The aim of this study was to evaluate the frequency of male accessory gland infections (MAGI) in patients with CBP plus IBS and to compare the sperm parameters of patients with or without MAGI. Fifty consecutive patients with the following criteria were enrolled: (i) infertility; (ii) diagnosis of CBP; and (iii) diagnosis of IBS according to the Rome III criteria. The following two aged-matched control groups were also studied: infertile patients with CBP alone (n = 56) and fertile men (n = 30) who fathered a child within the previous 3 months. Patients and controls underwent to an accurate anamnesis, administration of the NIH-Chronic Prostatitis Symptom Index (NIH-CPSI) and the Rome III questionnaires for prostatitis and IBS, respectively, physical examination, and semen analysis. A significantly higher frequency of MAGI was found in patients with CBP plus IBS (82.0%) compared with the patients with CBP alone (53.6%) or the fertile men (0%). The presence of MAGI in the patients with CBP plus IBS was associated with a significantly lower sperm concentration, total number, and forward motility, and with a higher seminal leucocyte concentration compared with the patients with CBP alone and MAGI. Sperm normal morphology was similar in the groups of patients. All sperm parameters did not differ significantly in both the groups of patients without MAGI. The patients with CBP plus IBS had a significantly higher frequency of MAGI compared with the patients with CBP alone. This was associated with worse sperm parameters and, hence, poorer reproductive prognosis. We suggest to search for the presence of IBS in the patients with PS and in particular when CBP and/or worse sperm parameters are present.     

The effect of adjuvant vitamin C after varicocele surgery on sperm quality and quantity in infertile men: a double blind placebo controlled clinical trial

Varicocele is one of the most common causes of male infertility and spontaneous pregnancy rate after varicocelectomy is only about 30%. The most important seminal antioxidant is vitamin C but recent studies about the effects of vitamin C on spermatogenesis are controversial; therefore, we decided to evaluate its role after varicocelectomy. In a double blind randomized controlled clinical trial, 115 men with infertility and clinical varicocele with abnormal semen analyses were recruited. After surgery, the intervention group received vitamin C (250 mg bid) and the control group received placebo for three months. Mean sperm count, motility, and morphology index of two semen analyses (before and after surgery) were compared between the two groups. Univariate general linear model and stepwise linear regression were used in analysis. The mean age (±SD) of participants was 27.6±5.3 years. Vitamin C group had statistically significant better normal motility (20.8 vs. 12.6, P=0.041) and morphology (23.2 vs. 10.5, P<0.001) than placebo group. Considering the values prior to surgery as covariate, vitamin C was not effective on sperm count (P=0.091); but it improved sperm motility (P=0.016) and morphology (P<0.001) even after excluding the confounding effect of age (P=0.044 and P=0.001, respectively). Vitamin C was also an independent factor in predicting motility and normal morphology after surgery. Ascorbic acid can play a role as adjuvant treatment after varicocelectomy in infertile men.     

Sperm motility in fertile men and males in infertile units: in vitro test

An in vitro test evaluating spermatozooan motility was used to compare percentage of forward progressive spermatozooa at initial observation, within 1 h of obtaining samples, with forward progression after 8 h in Petri dishes (humid chambers). A constant motility profile was found in the sperm of fertile men after 8 h, whereas a different profile was found in 94% of the infertile male groups.     

Cytochemical evaluation of sperm chromatin and DNA integrity in couples with unexplained recurrent spontaneous abortions

The aim of this study was to examine the possible relationship between sperm DNA integrity and chromatin packaging evaluated by cytochemical assays, traditional sperm parameters and recurrent spontaneous abortion (RSA) of unknown origin. In this cohort study, 40 couples with a history of RSA and 40 couples with proven fertility were considered as case and control groups respectively. The semen samples of all husbands were analysed for sperm parameters and also sperm chromatin and DNA integrity assessed using cytochemical tests including aniline blue (AB), chromomycin A3 (CMA3), toluidine blue (TB), acridine orange (AOT) and nuclear chromatin stability assay. Among different sperm parameters, only slow motility was significantly different between the two groups. In sperm chromatin evaluations, there were significant differences between the two groups in all of the tests. In addition, the majority of semen samples in RSA patients exhibited upper percentages of abnormal spermatozoa than the cut-off values regarding different cytochemical assays. Our study showed that in the cases of RSA, slow motility had a significant reduction in comparison with controls and also spermatozoa of men from RSA group had less chromatin condensation and poorer DNA integrity than spermatozoa that obtained from fertile men with no history of RSA.     

A maternal vegetarian diet in pregnancy is associated with hypospadias. The ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood

OBJECTIVE: To investigate the possible role of the maternal diet, particularly vegetarianism and consumption of phytoestrogens, in the origin of hypospadias, which is reported to be increasing in prevalence. SUBJECTS AND METHODS: Detailed information was obtained prospectively from mothers, including previous obstetric history, lifestyle and dietary practices, using structured self-completed questionnaires during pregnancy. Previously recognized associations with environmental and parental factors were examined, focusing particularly on the hypothesized hormonal link. Multivariate logistic regression was used to identify independent associations. RESULTS: Of 7928 boys born to mothers taking part in the Avon Longitudinal Study of Pregnancy and Childhood, 51 hypospadias cases were identified. There were no significant differences in the proportion of hypospadias cases among mothers who smoked, consumed alcohol or for any aspect of their previous reproductive history (including the number of previous pregnancies, number of miscarriages, use of the contraceptive pill, time to conception and age at menarche). Significant differences were detected for some aspects of the maternal diet, i.e. vegetarianism and iron supplementation in the first half of pregnancy. Mothers who were vegetarian in pregnancy had an adjusted odds ratio (OR) of 4.99 (95% confidence interval, CI, 2.10-11.88) of giving birth to a boy with hypospadias, compared with omnivores who did not supplement their diet with iron. Omnivores who supplemented their diet with iron had an adjusted OR of 2.07 (95% CI, 1.00-4.32). The only other statistically significant association for hypospadias was with influenza in the first 3 months of pregnancy (adjusted OR 3.19, 95% CI 1.50-6.78). CONCLUSION: As vegetarians have a greater exposure to phytoestrogens than do omnivores, these results support the possibility that phytoestrogens have a deleterious effect on the developing male reproductive system.     

The effective cumulative pregnancy rate of different modes of treatment of male infertility

Summary.  The clinical efficacy of conventional and advanced methods of treatment was assessed in 814 couples with infertility due to a male factor. The monthly and effective cumulative rate of ongoing or term pregnancies was calculated during 4712 couple-months. Treatment of varicocele by transcatheter embolization, resulting in 3.9% pregnancies per cycle and an effective cumulative pregnancy rate of 41% after 1 year, is more effective than counselling and timed intercourse (9% pregnancies after 12 months). Intrauterine insemination (IUI) of washed spermatozoa produced 17% pregnancies in the initial 4 months, but the success rate of the subsequent cycles (1.7% per cycle) was not different from that of the controls.
In vitro fertilization (IVF) resulted in 16% pregnancies per attempt, but the effective cumulative pregnancy rate was only 31% in 12 months due to the long interval between treatment attempts and the high drop-out rate. With subzonal micro-injection of sperm, the fertilization rate was higher (71%) than with regular IVF (29%) but both the pregnancy rate per attempt (9%) and the effective cumulative pregnancy rate (17% after 12 months) were low.
The 10th percentile of sperm characteristics (cut-off values) of successful cases showed intrauterine insemination to be advantageous in cases with a lower percentage of spermatozoa with progressive motility (9%) than in the controls (15%). The cut-off value of sperm morphology in IVF (4%) is lower than that of IUI (8%) and of the controls (9%), but higher than that of subzonal insemination (1%).
Treatment strategy must be defined selecting or combining conventional and assisted reproductive technology for each individual couple with male factor infertility.     

Melatonin hormone profile in infertile males

Melatonin is a hormone produced by the pineal gland. There is much controversy about its relationship to the male reproductive process. In this study, seminal plasma as well as the serum melatonin levels were studied in different infertile male groups and were correlated with their semen parameters and hormonal levels. One hundred twenty male cases subdivided into six equal groups were consecutively included; fertile normozoospermic men, oligoasthenozoospermia (OA), OA with leucocytospermia, OA with varicocele, non-obstructive azoospermia (NOA) with high serum follicle stimulating hormone (FSH) and NOA with normal FSH. Semen analysis, estimation of melatonin, FSH, testosterone (T) and prolactin (PRL) hormone was carried out. Mean level of serum melatonin was higher than its corresponding seminal concentrations in all investigated groups with a positive correlation between their levels (r = 0.532, p = 0.01). Serum and seminal plasma melatonin levels in all infertile groups were reduced significantly compared with their levels in the fertile group. The lowest concentrations were in OA with leucocytospermia group. Melatonin in both serum and semen demonstrated significant correlation with sperm motility (r = 607, 0.623 respectively, p = 0.01). Serum melatonin correlated positively with serum PRL (r = 0.611, p = 0.01). It may be concluded that melatonin may be involved in the modulation of reproductive neuroendocrine axis in male infertility. Also, low levels of melatonin in semen were observed in infertile groups having reduced sperm motility, leucocytospermia, varicocele and NOA.