Semen assessment

Understanding sperm motility mechanisms and the implication of sperm surface molecules in promoting motility

Background

It is estimated that approximately 8–12% of couples globally face problems associated with infertility. A large number of men exhibit suboptimal sperm parameters. Sperm motility is one of the factors that is measured when analysing sperm parameters. The indication of several crucial sperm surface molecules, having the ability to modulate motility, has opened new avenues in understanding the complex processes involved in motility.

Main body of the abstract

There are various mechanisms that regulate and enhance sperm motility. Several surface molecules on sperm cells can also regulate motility, thus showing their possible application as a treatment for infertility caused by impaired motility. Sperm motility is regulated by intracellular and extracellular pH, along with calcium ions (Ca2+) and carbonate ion (HCO3−) concentrations. Moreover, sperm cells have an array of surface proteins which play a critical role in their function and motility. The indication of surface molecules presented new opportunities for understanding sperm motility and the possibility of treating infertility caused by impaired sperm function. Infertility and problems associated with conception can cause underlying stress and mental trauma. Although there are several methods for treating infertility, most are complex, invasive, and expensive.

Conclusion

It is important to understand how surface molecules and proteins on the sperm cell regulate motility. This will enable us to treat anomalies associated with proper sperm function. This review highlights the general mechanisms that regulate sperm motility, and it stresses the importance and relevance of sperm surface molecules in regulating sperm motility.

Spontaneous pregnancies and determinant factors in infertility: A cross-sectional study

Background

The phenomenon of infertility may be derived from different factors - either in males or females or both genders, including few unexplained factors. It is generally managed by medical and surgical treatments.

Objective

To find a relation of occurrence of spontaneous pregnancy (SP) with effective factors in infertility.

Materials and Methods

This cross-sectional study was conducted at two referral infertility centers (university and privacy center) in the southwest of Iran from March 2015 and March 2016 on 655 infertile couples, who were divided in two groups of with (n = 31) and without (n = 624) SP. The variables included female and male age, male smoking, male job, the place of living, the causes of infertility, the type and duration of infertility, and the subgroups of infertility causes.

Results

Infertility may be caused due to both male- and female- related factors (47.5%). While female-related infertility was found in 31.5%, male-related infertility in 14.5%, and infertility due to unexplained factors in 6.6% of our patients. The rate of SP was 4.7%, which had a significant relation with the duration of infertility (p = 0.01), with women's age (p = 0.048), unexplained infertility (p = 0.001), and husband's job (p = 0.004).

Conclusion

The occurrence of SP in infertile couples was related to age of the female partner, the duration of unexplained infertility, and the male partner's job.

Ccdc87 is critical for sperm function and male fertility

Male infertility has become an increasingly common health concern in recent years. Apart from environmental factors, nutrition, lifestyle, and sexually transmitted diseases, genetic defects are important causes of male infertility. Many genes have been demonstrated to be associated with male infertility. However, the roles of some functional genes in infertility, especially those that are specifically expressed in the reproductive system, remain to be elucidated. Here, we demonstrated that the testis-specific gene coiled-coil domain-containing 87 (Ccdc87) is critical for male fertility. Reverse-transcriptase polymerase chain reaction and western blot analyses revealed that the Ccdc87 mRNA and protein were only expressed in mouse testis. Ccdc87 expression first appeared at postnatal day 14 and remained at a relatively high level until adulthood. Male mice lacking Ccdc87 gene (Ccdc87-/-) were found to be subfertile. Approximately 20% of Ccdc87-null sperm from the testis and epididymis displayed severe abnormity of acrosome and cell nucleus. Sperm isolated from the cauda epididymides of Ccdc87-/- mice exhibited decreased initial motility but did not show any change in capacitation. Additionally, Ccdc87 disruption led to the impotency of sperm spontaneous and progesterone-induced acrosome reaction. Moreover, in vitro fertilization assays indicated that the fertilizing capacity of Ccdc87-/- sperm was significantly reduced. Taken together, these findings provide a new clue to understand the genetic causes of male infertility.

Semen Quality in Chinese College Students: Associations With Depression and Physical Activity in a Cross-Sectional Study

OBJECTIVE

Behavioral and psychosocial factors have been associated with a decline of the quality of semen. However, the relationship of depression and physical activity (PA) with semen quality remains unclear.

METHODS

Data were obtained from 587 young male Chinese college students in June 2013. Participants completed a questionnaire assessing life-style factors, the Zung self-rated depression scale, and three items related to PA. They underwent a physical examination and provided a semen sample and a blood sample for reproductive hormones (testosterone, estrogen, progesterone, follicle-stimulating hormone, luteinizing hormone, and prolactin).

RESULTS

Men with high depression scores (n = 63, 10.7%) had lower sperm concentration (M (SD) = 66.9 (74.5) versus 72.6 (56.9) [10/ml], p = .043) and total sperm count (M (SD) = 241.6 (299.7) versus 257.0 (204.0) [10], p = .024) than nondepressed men. Participants with low PA levels (n = 99, 16.9%) had lower total sperm count (M (SD) = 204.4 (153.7) versus 265.8 (225.8) [10/ml], p = .017) than participants with higher activity levels. After adjusting for potential confounders, depressed men had 18.90% (95% confidence interval [CI] = 1.14%-33.47%) lower sperm concentration and 21.84% (95% CI = 3.39%-36.90%) lower total sperm count than nondepressed men. Men with low PA levels had 23.03% (95% CI = 2.80%-46.89%) lower total sperm count than physically active participants. An interaction effect between depression and PA on sperm concentration was detected (p = .033). There were no significant associations of depression and PA with reproductive hormones (p > .05).

CONCLUSIONS

Depression and low levels of PA are associated with lower levels of semen quality, which may have implications for reproductive health.

Social support modifies an association between work stress and semen quality: Results from 384 Chinese male workers

OBJECTIVE

Psychosocial factors have been associated with a decline of the quality of semen. The study was aimed at (i) estimating the association between work stress and semen quality and (ii) exploring the moderating effect of social support in semen parameters among Chinese male workers.

METHODS

Data were obtained from 384 adult male workers recruited from April 2014 to December 2015 in Chongqing, China. Participants completed a questionnaire assessing demographic and life-style factors. Work stress and social support was measured by the Chinese version of a 22-item Job Content Questionnaire (JCQ). They underwent a physical examination and provided a semen sample.

RESULTS

Subjects with high work stress were associated with a higher risk of being classified below WHO's thresholds for "normal," defined by sperm concentration (OR 2.14, 95% CI 1.24-3.68, p = .006) or total sperm count (OR 1.95, 95% CI 1.13-3.36, p = .02) criteria than subjects with low work stress were. However, these adverse associations were not observed among subjects with high social support (p = .80 for sperm concentration, and p = .39 for total sperm count). Interaction effects between social support and work stress on sperm concentration (p = .002) and total sperm count (p = .02) were detected.

CONCLUSION

Work stress is associated with lower levels of semen quality. Social support attenuates the negative association between work stress and semen quality, which may have implications for reproductive health.

On the Origins of the Semen Analysis: A Close Relationship with the History of the Reproductive Medicine

The spermatozoa were first seen in ejaculates in the 17^th century. However, the basic mechanisms of human fertilization have been only fully understood after the discovery of ovum in 1827. As a result, the interest in developing technologies for semen analysis arose from the early 1900s. Indeed, standard methodologies for semen analysis were designed mostly along the first half of the 20^th century. Before the 1930s, semen analysis was nearly unavailable clinically, since there were still no robust methodologies for assessing sperm characteristics, as well as to set up standard references that could be able to assess the reproductive capacity of men. However, joining some methodologies reported from 1910 up to 1930, standardization was attained and thereby semen analysis increasingly assumed its role in laboratory practice for investigating men in barren marriage. This article aims in reviewing historical backgrounds on the semen analysis, up to its insertion in laboratory practice. Emphasis is given to the major studies that contributed either directly or indirectly in developing the earliest routine for the semen analysis.

Study of pentoxifylline effects on motility and viability of spermatozoa from infertile asthenozoospermic males

BACKGROUND

The quality of semen is one of the major parameters in male infertility. Pentoxifylline, a methylxanthine derivative, is an agent primarily used in the treatment of intermittent claudication and other vascular disorders. Studies have shown that pentoxifylline enhances the quality and quantity of sperms. In this study, we have investigated the in vitro effects of pentoxifylline on viability and motility of spermatozoa in samples of infertile oligoasthenozoospermic males.

MATERIALS AND METHODS

In this observer-blinded clinical trial, semen samples of 25 infertile oligoasthenozoospermic males were collected in Alzahra Educational Medical Center of Tabriz University of Medical Sciences from August 2010 to August 2012. After the isolation of spermatozoa by the swim-up method, they were randomized into four groups in ISM1 environment: The controls treated normally: Group 1 treated by pentoxifylline at a dose of 50 μg/ml, Group 2 treated by pentoxifylline at a dose of 100 μg/ml, and Group 3 treated by pentoxifylline at a dose of 200 μg/ml. Sperm viability and motility were compared among the groups on 45 min, 24 h, 36 h, and 48 h intervals.

RESULTS

Mean percentages of live sperms were 98.40%, 51.40%, 20.60%, and 6.00% in control group and 98.40%, 69.20%, 38.60%, and 14.60% in Group 3 on the mentioned intervals, respectively. This mean percentage decrease of live sperms was significantly lower in Group 3 comparing with that of other groups (P = 0.01). Mean percentages of motile sperms were 54%, 8.40%, 2.80%, and 0% in control group; and 54%, 16%, 4.80%, and 1.40% in Group 3 on the mentioned intervals, respectively. There was not a significant difference between the four groups in this regard (P = 0.19).

CONCLUSION

Pentoxifylline can enhance the viability of sperm of infertile oligoasthenozoospermic males with no significant effect on its motility.

Fertility Preservation in Children and Adolescents

Fertility preservation is the process by which either oocytes (eggs) or sperm undergo an intervention to preserve their use for future attempts at conception. Consideration of fertility preservation in the pediatric and adolescent population is important, as future childbearing is usually a central life goal. For postpubertal girls, both oocyte and embryo cryopreservation are standard of care and for postpubertal boys, sperm cryopreservation continues to be recommended. Although all the risks are unknown, it appears that fertility preservation in most cases does not worsen prognosis, allows for the birth of healthy children, and does not increase the chance of recurrence.

Lifestyles Associated With Human Semen Quality: Results From MARHCS Cohort Study in Chongqing, China

Decline of semen quality in past decades is suggested to be potentially associated with environmental and sociopsychobehavioral factors, but data from population-based cohort studies is limited. The male reproductive health in Chongqing College students (MARHCS) study was established in June 2013 as a perspective cohort study that recruited voluntary male healthy college students from 3 universities in Chongqing. The primary objectives of the MARHCS study are to investigate the associations of male reproductive health in young adults with sociopsychobehavioral factors, as well as changes of environmental exposure due to the relocation from rural campus (in University Town) to metro-campus (in central downtown). A 93-item questionnaire was used to collect sociopsychobehavioral information in manner of interviewer-interviewing, and blood, urine and semen samples were collected at the same time. The study was initiated with 796 healthy young men screened from 872 participants, with a median age of 20. About 81.8% of this population met the WHO 2010 criteria on semen quality given to the 6 routine parameters. Decreases of 12.7%, 19.8%, and 17.0%, and decreases of 7.7%, 17.6%, and 14.7% in total sperm count and sperm concentration, respectively, were found to be associated with the tertiles of accumulated smoking amount. Fried food consumption (1-2  times/wk or ≥3  times/wk vs nonconsumers) was found to be associated with decreased total sperm count (10.2% or 24.5%) and sperm concentration (13.7% or 17.2%), respectively. Coffee consumption was found to be associated with increased progressive and nonprogressive motility of 8.9% or 15.4% for subjects consuming 1-2  cups/wk or ≥3  cups/wk of coffee, respectively. Cola consumption appeared an association with decreased semen volume at 4.1% or 12.5% for 1-2  bottles/wk or ≥3  bottles/wk. A cohort to investigate the effects of environmental/sociopsychobehavioral factors act on semen quality was successfully set up. We found smoking, coffee/cola/fried foods consumption to be significantly associated with semen quality from the baseline investigation.

Next day determination of ejaculatory sperm motility after overnight shipment of semen to remote locations

PURPOSE

To develop a method for delayed assessment of sperm motility, after shipment of semen to a remote laboratory. Sperm in semen were labeled with the MitoTracker(®) Red CM-H(2)XRos reagent, and fixed with 3.7 % formaldehyde by the laboratory technicians at the origin of the semen. This treatment reflected well sperm mitochondrial activity, and the MitoTracker(®) signal was related to sperm motility and velocity for 2-3 days following ejaculation.

METHODS

Sperm motility and velocity were evaluated manually and by computer assisted semen analysis (CASA), respectively. Fluorescence assessment of individual sperm was carried out with the computer assisted Metamorph v4.6.9 program. Emission levels of MitoTracker(®) spermatozoa were studied in room temperature and cooled semen, or in the respective room temperature swim-up sperm fractions following ejaculation, and on the second day (N = 103 samples, 89 men) and third day (N = 10 samples, 8 men).

RESULTS

Sperm with optical density (O.D.) ≥0.7 showed close correlations with ejaculatory sperm motility and velocity even after second day (r = 0.92, p < 0.001, N = 103 samples). Further, the multiple of sperm motility and velocity was also related to the proportion of high MitoTracker(®) reagent emission sperm (r = 0.83, p < 0.001, N = 103 samples). MitoTracker(®) dye fluorescence on the second day accurately reflected the ejaculatory sperm motility (r = 0.90, p < 0.001). Thus, a shipping delay would not adversely affect the results.

CONCLUSIONS

The delayed assessment of sperm motility in samples treated with MitoTracker(®) Red CM-H(2)XRos reagent and shipped to remote laboratory truly reflects the level of sperm motility at the time of the ejaculation.