Sperm Function Tests Research Articles

Heparin binding proteins and their relationship with vital sperm function tests vis-à-vis fertility of buffalo bull semen

ObjectiveTo characterize HBP of seminal plasma, fresh- and frozen-thawed sperm extracts and determine their relationship with post-thaw sperm function tests and bull fertility. MethodsBoth fresh (1–2 ml) and frozen semen (50 straws per bull) were collected from thirty breeding Murrah buffalo bulls and subjected to immunoblotting. Further, frozen-thawed semen was evaluated for first service conception rate (FSCR), percent acrosome reaction, hypoosmotic swelling test (HOST), viability, DNA integrity and total motility and linked to HBP. ResultsFourteen immunoreactive bands in seminal plasma (135, 75, 70, 65, 60, 55, 45, 37, 33, 31, 28, 24, 18 and 16 kDa), twelve in fresh sperm extracts (75, 70, 65, 55, 48, 37, 31, 28, 24, 20, 16 and 11 kDa) and thirteen in frozen-thawed spermatozoa (135, 100, 75, 70, 65, 55, 48, 45, 37, 31, 28, 24 and 20 kDa) were detected in western blots. In seminal plasma, fresh- and frozen-sperm extracts, bulls positive for 70 and 18 kDa; 55 kDa and 135, 75, 55, 45, 28 and 24 kDa, respectively, had higher (P < 0.05) FSCR as compared to their negative counterparts and had also higher (P < 0.05) percentages of most seminal parameters in positive ones. The antibody binding was most prevalent in acrosomal and postacrosomal regions of head in majority of spermatozoa. ConclusionWe have identified buffalo bull seminal HBP that influence semen quality and subsequent fertility of bulls.

Editorial Comment

Semen analyses remain the foundation of andrological work-up in the evaluation of male fertility and infertility. It is highly quantitative based on visual parameters and does not usually take into consideration the functionality of the sperm itself as measured by certain other parameters such as reactive oxygen species (ROS) and/or DNA fragmentation. 1 Lamb D. Semen analysis in 21st century medicine: the need for sperm function testing. Asian J Androl. 2010; 12: 64-70 Crossref PubMed Scopus (48) Google Scholar These have been shown to potentially affect pregnancy outcomes along with quantitative parameters. Semen parameters rely on the physiological and pathophysiological mechanisms of spermato genesis in the seminiferous tubules; the cycle of production; issues of processing and transportation through the reproductive tract; storage in the reproductive tract; and the natural degradation process of the sperm if not ejaculated. All these factors influence clinical management. As such, one of the simplest ways to consider this process and the quality of semen parameters is the abstinence period since last ejaculation, but the exact time frame is not completely defined in the literature. 2 Amann R.P. Considerations in evaluating human spermatogenesis on the basis of total sperm per ejaculate. J Androl. 2009; 30: 626-641 Crossref PubMed Scopus (34) Google Scholar How frequent is too frequent for ejaculation to deplete the sperm stored or produced or time to “restock” between ejaculations? How long is too long before sperm is broken down or become ‘stagnant”? 3 Mortimer D. Templeton A.A. Lenton E.A. Coleman R.A. Influence of abstinence and ejaculation-to-analysis delay on semen analysis parameters of suspected infertile men. Arch Androl. 1982; 8: 251-256 Crossref PubMed Scopus (45) Google Scholar , 4 Correa-Pérez J.R. Fernández-Pelegrina R. Aslanis P. Zavos P.M. Clinical management of men producing ejaculates characterized by high levels of dead sperm and altered seminal plasma factors consistent with epididymal necrospermia. Fertil Steril. 2004; 8: 1148-1150 Abstract Full Text Full Text PDF Scopus (20) Google Scholar The World Health Organization (WHO) Laboratory Manual for the Examination and Processing of Human Semen (5th Edition) 2010, which is viewed as the authoritative text on the matter, states, “The sample should be collected after a minimum of 2 days and a maximum of 7 days of sexual abstinence. If additional samples are required, the number of days of sexual abstinence should be as constant as possible at each visit.” 5 Cooper T.G. Keck C. Oberdieck U. Nieschlag E. Effects of multiple ejaculations after extended periods of sexual abstinence on total, motile and normal sperm numbers, as well as accessory gland secretions, from healthy normal and oligozoospermic men. Hum Reprod. 1993; 8: 1251-1258 PubMed Google Scholar , 6 Tyler J.P. Crockett N.G. Driscoll G.L. Studies of human seminal parameters with frequent ejaculation. I. Clinical characteristics. Clin Reprod Fertil. 1982; 1: 273-285 Google Scholar , 7 De Jonge C. LaFromboise M. Bosmans E. Ombelet W. Cox A. Nijs M. Influence of the abstinence period on human sperm quality. Fertil Steril. 2004; 82: 57-65 Abstract Full Text Full Text PDF PubMed Scopus (91) Google Scholar Amann and Chapman performed an eloquent study in 2009 that showed that to obtain meaningful values for diagnosis and distinguishing men with high or low sperm production and that the best abstinence period was more in the 42-54 hour time frame to an upper limit of 64 hours. 8 Amann R.P. Chapman P.L. Total sperm per ejaculate of men: obtaining a meaningful value or a mean value with appropriate precision. J Androl. 2009; 30: 642-649 Crossref PubMed Scopus (20) Google Scholar For men producing few sperm, up to 7 days was recommended. 8 Amann R.P. Chapman P.L. Total sperm per ejaculate of men: obtaining a meaningful value or a mean value with appropriate precision. J Androl. 2009; 30: 642-649 Crossref PubMed Scopus (20) Google Scholar

Testicular microlithiasis: Correlation with doppler sonography of testicular arteries and sperm function.

To determine the prevalence of testicular microlithiasis and its correlation with Doppler parameters of testicular arteries and sperm function. Reports of 1,200 consecutive scrotal sonographic examinations performed at our hospital were reviewed. Patients diagnosed with testicular microlithiasis were recalled for detailed scrotal sonographic examination, including Doppler sonography and sperm function. The same examinations were performed in an age-matched control group and the findings compared. Testicular microlithiasis was found in 64 cases (5.3%). Doppler sonography showed mean resistance index, Vmax, and Vmin of 61.1 ± 9.3%, 18.2 ± 4.7 cm/s, and 7.7 ± 2.3 cm/s, respectively, in the testicular microlithiasis group versus 62.4 ± 10.4%, 18.4 ± 5.7 cm/s, and 7.3 ± 2.4 cm/s, respectively, in the control group (p = 0.49, 0.84 and 0.35, respectively). Sperm function tests demonstrated sperm count, motility, and normal morphology (normal oval head) of 29.6 ± 20.4 × 10(6) /mL, 35.3 ± 16.2%, and 44.4 ± 12%, respectively, in patients with testicular microlithiasis versus 54.3 ± 22.4 × 10(6) /mL, 50.2% ± 14.4%, and 66.4 ± 11.6% in control subjects (p < 0.02). Prevalence of testicular microlithiasis of 5.3% in Jordanian patients is similar to what has been reported in the literature. Testicular microlithiasis does not have a significant effect on Doppler parameters of testicular arteries. The apparent impairment of sperm function in patients with testicular microlithiasis warrants further studies. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:474-479, 2016.

Characterization of tissue inhibitor metalloproteinases in semen and their relationship with vital sperm function tests vis-à-vis fertility of breeding buffalo bulls

The present study was undertaken to separate and compare the tissue inhibitor metalloproteinases (TIMP) of seminal plasma and frozen-thawed sperm extracts from 30 buffalo bulls by immunoblotting and determine a relationship between various TIMP with post-thaw sperm function tests vis-à-vis bull fertility. Seven immunoreactive bands in seminal plasma (65, 55, 48, 33, 31, 24 and 11 kDa) and 5 in frozen-thawed spermatozoa (75, 65, 55, 24 and 16 kDa) were detected in Western blots following incubation (TIMP–140) and subsequent washing in vitro, indicating that TIMP is bound to sperm membranes. The frozen-thawed semen was evaluated for first service conception rate (FSCR), per cent HOST, acrosome reaction, viability, DNA integrity and total motility and linked to TIMP. In seminal plasma, the bulls positive for 48, 33 and 24 kDa TIMP had significantly higher FSCR (57.0 ± 2.6 vs 27.0 ± 2.4%, 55.7 ± 3.0 vs 31.3 ± 3.2% and 45.0 ± 3.8 vs 32.8 ± 4.7%, respectively) as compared to their negative counterparts. Except per cent viability, almost all seminal parameters (acrosome reaction, per cent HOST, DNA integrity and total motility) were significantly higher in bulls positive for TIMP of 48, 33, 31 and 24 kDa than in their negative contemporary mates. In frozen-thawed sperm extracts, the bulls positive for TIMP–24 had significantly higher FSCR (51.7 ± 3.7 vs 27.2 ± 3.0%), higher percentage of acrosome-reacted (55.9 ± 2.8 vs 48.9 ± 2.2%) and HOS-positive (69.2 ± 1.5 vs 65.3 ± 1.9%) spermatozoa in comparison to their negative herd mates. These results suggested that TIMP influences semen quality and subsequent fertility of buffalo bulls through inhibition of metalloprotease activity in semen.

Effects of mechanical stresses on sperm function and fertilization rate in mice

ABSTRACTIn this study, we investigated whether any of the observed changes in mouse sperm function tests secondary to mechanical stresses (centrifugation and pipetting) correlate with sperm fertilization ability. Chinese Kunming mice were used as sperm and oocyte donors. Sperm samples were allocated evenly into centrifugation, pipette, and control groups. Sperm plasma membrane integrity (PMI), mitochondrial membrane permeability (MMP), baseline and stimulated intracellular ROS, and sperm fertilization ability were measured by hypo-osmotic swelling, flow cytometry, and fertilization tests. Parallel studies were conducted and all tests were repeated six times. Our results showed that after centrifugation, the progressive motility, average path velocity, and overall sperm motility and PMI decreased significantly (p < 0.05). In addition, the MMP level decreased significantly in viable sperm when the centrifugation condition reached 1,400 g × 15 minutes (p < 0.05). When pipetting was performed two or more times, progressive motility, average path velocity, and overall sperm motility decreased significantly (p < 0.05); when it was performed four or more times, sperm membrane integrity and intracellular basal ROS level of viable sperm was also significantly decreased (p < 0.05). In conclusion, various mechanical stresses seem to affect sperm function, however this does not appear to alter fertilization rate. Laboratory handling steps should be minimized to avoid unnecessary mechanical stresses being applied to sperm samples.

Summary evidence on the effects of varicocele treatment to improve natural fertility in subfertile men.

The objective of this review was to summarize the evidence concerning the benefit of varicocele treatment to improve natural fertility in subfertile males. We also analyzed the effect of varicocele treatment on conventional semen parameters and sperm functional tests. An electronic search to collect the data was performed using the PubMed/MEDLINE databases until July 2015. Data pooled from a variety of study designs indicate that varicocelectomy improves semen parameters in the majority of the treated men with clinical varicocele and abnormal semen parameters regardless of the chosen surgical method. Surgical varicocele repair was beneficial not only for alleviating oxidative stress-associated infertility but also to improve sperm nuclear DNA integrity. However, given the low magnitude of the effect size in sperm DNA integrity, further research is needed to elucidate its clinical significance. Conflicting results on the effect of varicocele treatment on natural fertility seem to be due to heterogeneous study designs and, more importantly, patient selection criteria. When these issues are controlled, current evidence indicates that treatment of subclinical varicocele is not warranted, as it does not seem to improve fertility. On the contrary, fair evidence indicates that varicocele treatment should be offered to infertile patients with palpable varicocele and abnormal semen parameters. This evidence supports the current guidelines issued by the American Urological Association and European Association of Urology, which state that varicocele treatment should be offered to male partners of infertile couples presenting for evaluation with clinical varicocele and semen parameters alterations.

Effects of Synthetic Serum Supplementation in Sperm Preparation Media on Sperm Capacitation and Function Test Results

Albumin supplementation of culture media induces sperm capacitation in assisted reproduction technique cycles. Synthetic serum supplementation is clinically used to replace albumin for preventing transmission of infectious agents. However, the effects of synthetic serum supplementation on sperm capacitation have rarely been investigated. Spermatozoa from 30 men with normal basic semen analysis results were collected, divided into five aliquots, and cultured in capacitating conditions in four combinations of two synthetic serum supplements, serum substitute supplement (SSS) and serum protein substitute (SPS), and two fertilization media, Quinns Advantage™ Fertilization (QF) and human tubular fluid (HTF) media. Reactive oxygen species (ROS) levels in spermatozoa were measured through chemiluminescence. Furthermore, acrosome reaction and western blotting for tyrosine phosphorylation were used to evaluate sperm capacitation. HTF+SSS had significantly higher ROS levels than QF+SPS did (11,725 ± 1,172 versus 6,278 ± 864 relative light units). In addition, the spermatozoa cultured in QF+SPS had lower motility, acrosome reaction rates, and tyrosine phosphorylation levels compared with those cultured in HTF+SSS. In conclusion, the effects of synthetic serum supplementation on sperm capacitation varied according to the combination of media. These differences may lead to variations in spermatozoon ROS levels, thus affecting sperm function test results.

Semen Analysis and Sperm Function Tests as Diagnostic Tools for Male Animals’ Infertility

Semen Analysis and Sperm Function Tests as Diagnostic Tools for Male Animals’ Infertility

Specialized sperm function tests in varicocele and the future of andrology laboratory

Varicocele is a common medical condition entangled with many controversies. Though it is highly prevalent in men with infertility, still it marks its presence in males who do have normal fertility. Determining which patients are negatively affected by varicocele would enable clinicians to better select those men who benefitted the most from surgery. Since conventional semen analysis has been limited in its ability to evaluate the negative effects of varicocele on fertility, a multitude of specialized laboratory tests have emerged. In this review, we examine the role and significance of specialized sperm function tests with regards to varicocele. Among the various tests, analysis of sperm DNA fragmentation and measurements of oxidative stress markers provide an independent measure of fertility in men with varicocele. These diagnostic modalities have both diagnostic and prognostic information complementary to, but distinct from conventional sperm parameters. Test results can guide management and aid in monitoring intervention outcomes. Proteomics, metabolomics, and genomics are areas; though still developing, holding promise to revolutionize our understanding of reproductive physiology, including varicocele.

Seminal biomarkers for the evaluation of male infertility.

For men struggling to conceive with their partners, diagnostic tools are limited and often consist of only a standard semen analysis. This baseline test serves as a crude estimation of male fertility, leaving patients and clinicians in need of additional diagnostic biomarkers. Seminal fluid contains the highest concentration of molecules from the male reproductive glands, therefore, this review focuses on current and novel seminal biomarkers in certain male infertility scenarios, including natural fertility, differentiating azoospermia etiologies, and predicting assisted reproductive technique success. Currently available tests include antisperm antibody assays, DNA fragmentation index, sperm fluorescence in situ hybridization, and other historical sperm functional tests. The poor diagnostic ability of current assays has led to continued efforts to find more predictive biomarkers. Emerging research in the fields of genomics, epigenetics, proteomics, transcriptomics, and metabolomics holds promise for the development of novel male infertility biomarkers. Seminal protein-based assays of TEX101, ECM1, and ACRV1 are already available or under final development for clinical use. Additional panels of DNA, RNA, proteins, or metabolites are being explored as we attempt to understand the pathophysiologic processes of male infertility. Future ventures will need to continue data integration and validation for the development of clinically useful infertility biomarkers to aid in male infertility diagnosis, treatment, and counseling.

Sperm DNA fragmentation and mitochondrial membrane potential combined are better for predicting natural conception than standard sperm parameters

To evaluate whether DNA fragmentation and/or mitochondrial membrane potential (MMP) predict natural conception better than standard sperm parameters. Prospective cross-sectional study. University medical center. Eighty-five infertile and 51 fertile men. Assessment of sperm DNA fragmentation, MMP, and standard semen parameters over a 6- to 12-month observation period. Comparison between the results of DNA fragmentation, MMP, and standard sperm parameters alone or combined and achievement of natural conception. Twenty-six of the 85 (31%) men from infertile couples conceived naturally. The median values of DNA fragmentation and MMP in the men who conceived within the observation period were similar to those in the fertile controls. Optimal threshold values of DNA fragmentation and MMP were 25% as determined by receiver operating characteristic analysis (area under the curve [AUC], 0.70; 95% confidence interval (CI) 0.58-0.82) and 62.5% (AUC, 0.68, 95% CI 0.56-0.80), respectively. The men in the infertile group with values of DNA fragmentation ≤25% and with MMP values ≥62.5% had significantly higher odds for conception (odds ratio [OR], 5.22; 95% CI 1.82-14.93] and OR, 4.67; 95% CI 1.74-12.5, respectively). Normal semen analysis alone had no predictive value for natural conception (OR, 1.84; 95% CI 0.67-5.07]). Both sperm function tests combined had significant odds for natural conception (OR, 8.24; 95% CI 2.91-23.33]), with a probability of 0.607 (60.7%) for both normal values and 0.158 (15.8%) for abnormal values. Sperm DNA fragmentation and MMP combined may be superior to standard semen parameters for the prediction of natural conception.

The impact of obesity on male fertility.

Obesity in men of reproductive age is globally on the increase. There is clear evidence from epidemiological studies that obesity impacts negatively on male fertility; it is associated with hypogonadism, although it is less consistently linked to impaired spermatogenesis and tests of sperm function, including DNA fragmentation. Sperm from obese men used for in vitro fertilisation/intra cytoplasmic sperm injection is associated with a greater number of pregnancy losses and is less likely to result in live births. There are also increasing data from animal studies that paternal obesity may impact negatively on the reproductive and metabolic health of offspring and grand-offspring. It has been suggested that high-fat dietary exposures could affect the epigenetic content of sperm or the endocrine content of seminal fluid and thus impact early fetal development. Experimental and epidemiological data show that male fertility, and offspring health, can be improved by weight loss in obese and overweight males.

Impaired protamination and sperm DNA damage in a Nellore bull with high percentages of morphological sperm defects in comparison to normospermic bulls

The routine semen evaluation assessing sperm concentration, motility and morphology, does not identify subtle defects in sperm chromatin architecture. Bulls appear to have stable chromatin, with low levels of DNA fragmentation. However, the nature of fragmentation and its impact on fertility remain unclear and there are no detailed reports characterizing the DNA organization and damage in this species. The intensive genetic selection, the use of artificial insemination and in vitro embryo production associated to the cryopreservation process can contribute to the chromatin damage and highlights the importance of sperm DNA integrity for the success of these technologies. Frozen-thawed semen samples from three ejaculates from a Nellore bull showed high levels of morphological sperm abnormalities (55.8±5.1%), and were selected for complementary tests. Damage of acrosomal (76.9±8.9%) and plasma membranes (75.7±9.3%) as well as sperm DNA strand breaks (13.8±9.5%) and protamination deficiency (3.7±0.6%) were significantly higher compared to the values measured in the semen of five Nellore bulls with normospermia (24.3±3.3%; 24.5±6.1%; 0.6±0.5%; 0.4±0.6% for acrosome, plasma membrane, DNA breaks and protamine deficiency, respectively) (P&lt;0.05). Motility and percentage of spermatozoa with low mitochondrial potential showed no differences between groups. This study shows how routine semen analyses (in this case morphology) may point to the length and complexity of sperm cell damage emphasizing the importance of sperm function testing.

Prognostic factors for IVF success: diagnostic testing and evidence-based interventions.

Numerous tests and interventions have been proposed for optimizing performance in preparation for in vitro fertilization (IVF) treatment. We critically appraised the available evidence underpinning some of the popular investigations and treatments, including the role of hysteroscopy, laparoscopy, ovarian reserve tests, sperm function tests, as well as the role of lifestyle modifications or surgery for endometriosis, fibroids, and endometrial polyps. We also reviewed the evidence behind novel techniques, such as the use of endometrial injury before IVF. Only a few of the aforementioned modalities are justified based on the available research evidence. Other factors may affect the uptake of a test or intervention before IVF, namely the complexity of the proposed modality, its potential for harm, and its cost-effectiveness.

The need to improve patient care through discriminate use of intracytoplasmic sperm injection (ICSI) and improved understanding of spermatozoa, oocyte and embryo biology

D. T. Carrell, A. Nyboe Andersen and D. J. Lamb Departments of Surgery (Urology), Obstetrics and Gynecology, and Human Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA, The Fertility Clinic, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark, and The Center for Reproductive Medicine, Scott Department of Urology and the Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA

Semen Parameters as Predictors of Fertilization Success in Conventional Insemination Cases: Is Hyaluronan Binding Assay (HBA) More Sensitive in Normospermic Samples?

Semen analysis (SA) may provide initial diagnosis of male factor infertility. The reliability of repeated SA producing valuable prognostic information for in vitro fertilization (IVF) success is inconsistent. The risk of failed fertilization is low (∼5%) and the financial and emotional costs of an unsuccessful IVF cycle are significant1. HBA is a sperm function test that provides qualitative assessment of sperm quality, maturity, and fertilization potential by measuring the proportion of sperm bound to hyaluronan.

Relationship of Naturally Occurring Antisperm Antibodies in Blood Serum and Seminal Plasma of Cattle Bulls with Sperm Function and Fertility Tests

The study was planned with an objective to assess the level of antisperm antibodies (ASA) in the blood serum and seminal plasma of breeding cow bulls and their relationship with sperm function and fertility tests. ASA was analyzed in blood serum and seminal plasma by SpermMar test, Immuno peroxidase assay (IPA) and Enzyme linked immunoabsorbant assay (ELISA). In SpermMar test, about 54% bulls were with >40% IgG in blood serum against sperm surface antigens, whereas none of the bulls were with >10% IgG in seminal plasma. More than 20% and >10% IgA against sperm surface antigens were detected in the blood serum and seminal plasma of 65.8% and 37% bulls, respectively. Out of 26 bulls, seminal plasma of 21 bulls reacted with spermatozoa both in IPA and IgA latex particles and that of only 12 bulls reacted with IgG. In IPA, about 50% of the bulls had >40% ASA against head surface antigens, whereas, there were 23% bulls with >10% ASA in seminal plasma. Also ELISA indicated a higher antibody titre in blood serum (3200 - 6400) and seminal plasma (40 - 80) of 50% and 42% bulls, respectively. There were 11 bulls with low values of HOST/in vitro acrosome reaction/cervical mucus penetration assay and higher level of either serum or seminal plasma ASA. Our study revealed that a significant level of ASA in serum or seminal plasma may have effect on the fertility of bulls by affecting the sperm function.

Sperm function test.

With absolute normal semen analysis parameters it may not be necessary to shift to specialized tests early but in cases with borderline parameters or with history of fertilization failure in past it becomes necessary to do a battery of tests to evaluate different parameters of spermatozoa. Various sperm function tests are proposed and endorsed by different researchers in addition to the routine evaluation of fertility. These tests detect function of a certain part of spermatozoon and give insight on the events in fertilization of the oocyte. The sperms need to get nutrition from the seminal plasma in the form of fructose and citrate (this can be assessed by fructose qualitative and quantitative estimation, citrate estimation). They should be protected from the bad effects of pus cells and reactive oxygen species (ROS) (leukocyte detection test, ROS estimation). Their number should be in sufficient in terms of (count), structure normal to be able to fertilize eggs (semen morphology). Sperms should have intact and functioning membrane to survive harsh environment of vagina and uterine fluids (vitality and hypo-osmotic swelling test), should have good mitochondrial function to be able to provide energy (mitochondrial activity index test). They should also have satisfactory acrosome function to be able to burrow a hole in zona pellucida (acrosome intactness test, zona penetration test). Finally, they should have properly packed DNA in the nucleus to be able to transfer the male genes (nuclear chromatic decondensation test) to the oocyte during fertilization.

Assessment of accessory reproductive gland and oxidative stress in male partners of idiopathic recurrent pregnancy loss couples

Background: Etiologies behind recurrent pregnancy loss (RPL) in half of the cases remains idiopathic even after an extensive investigation. The role of oxidative stress (OS) has been implicated in the pathogenesis of many human diseases including male fertility, but its role on male partner of RPL couple is limited. Materials and Methods: Semen samples from fifty male partners of the female with the history of three or more idiopathic primary RPL and fifty controls were obtained and analyzed according to the WHO guidelines along with sperm function tests. Functioning of the accessory gland was evaluated selecting one marker for each gland such as citric acid and fructose. OS markers such as reactive oxygen species, total antioxidant capacity, lipid peroxidation, and superoxide dismutase levels were estimated. Statistical analysis was done using independent samples t -test using statistical software SPSS version 14. Results: In RPL group, significantly lower scores were observed for sperm function test than the control group. Fructose and citric acid levels did not show any significant difference between the groups. Among RPL group, 2% and 4.5% of individual have a lower value for fructose and citric acid, respectively. The malondialdehyde concentration and ROS levels were significantly higher in RPL group. While the activity of superoxide dismutase and total antioxidant level was significantly lower in RPL males than in the control group. Conclusion: This study highlights the importance of evaluation of male factors for sperm function tests, OS markers, and accessory gland assessment along with the conventional parameters. This may help for better pregnancy outcome through proper evaluations and management.

Urokinase-type plasminogen activator: a new target for male contraception?

Urokinase-type plasminogen activator (uPA) is closely related to male reproduction. With the aim of investigating the possibility for uPA as a potential contraceptive target, in the present work, Kunming male mice were immunized by human uPA subcutaneous injection at three separate doses for 3 times. Then the potency of the anti-human uPA antibody in serum was analyzed, and mouse fertility was evaluated. Serum antibody titers for human uPA in immunized groups all reached 1:10,240 or higher levels by enzyme linked immunosorbent assay, and mating experiments revealed that pregnancy rates and the mean number of embryos implanted after mating declined obviously (P < 0.05) when compared with control groups. However, the mating capacity and reproductive organ weights had no obvious change, and histological analysis of the testes and epididymides also showed normal morphology for immunized male mice. Sperm function tests suggested that the sperm concentration, sperm viability, sperm motility, and in vitro fertilization rate for the cauda epididymis sperm in uPA-immunized groups were lower than those in the controls (P < 0.05). Together, these observations indicated that subcutaneous injection human uPA to the male mice could effectively reduce their fertility, and uPA could become a new target for immunocontraception in male contraceptive development.