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Objective: To examine sperm motility, total antioxidant level (TAC), DNA fragmentation, and medical history in infertile men with high seminal high reactive oxygen species (ROS)., Design: Prospective study., Setting(s): Tertiary care hospital., Patient(s): Infertile men (n=101)., Intervention(s): Group I (n=57) included men with seminal ROS (<250 relative light units/sec/×10(6) sperm) while group II (n=44) included men with seminal ROS levels (≥250 relative light units/sec/×10(6) sperm)., Main Outcome Measure(s): Seminal ROS, TAC, sperm DNA fragmentation, ROS/TAC score were measured., Result(s): Group II had a high incidence of sperm DNA fragmentation than group I. The odds ratio of 1.25 for elevated ROS levels corresponded to >10% greater DNA fragmentation in our patients (95% confidence interval 1.01-1.53). Group II showed poor motility, a higher incidence of leukocytospermia, and higher ROS-TAC scores compared with group I. ROS was negatively correlated with sperm curvilinear velocity (r=-.24), linearity (r=-.24), and sperm motility (r=-.31). Sperm motility was correlated with %TUNEL(+ve) sperm (r=-.39)., Conclusion(s): An increase in seminal ROS levels by 25% was associated with a 10% increase in sperm DNA fragmentation. Sperm motility was affected by seminal ROS and sperm DNA fragmentation., (Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

In a longitudinal study over a period of 21 months, we demonstrated that seminal reactive oxygen species (ROS) levels are independent of sperm concentration, motility, and abstinence duration within a healthy sperm donor, although some variations were observed in ROS levels. We suggest that fluctuation in seminal ROS values may be related to physiologic or transient changes in spermatogenesis., (Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Reactive oxygen species (ROS) have a role in the modulation of gamete quality and gamete interaction. Generation of ROS is inherent in spermatozoa and contaminating leukocytes. ROS influence spermatozoa, oocytes, embryos and their environment. Oxidative stress (OS) mediates peroxidative damage to the sperm membrane and induces nuclear DNA damage. ROS can modulate the fertilizing capabilities of the spermatozoa. There is extensive literature on OS and its role in male infertility and sperm DNA damage and its effects on assisted reproductive techniques. Evidence is accumulating on the role of ROS in female reproduction. Many animal and human studies have elucidated a role for ROS in oocyte development, maturation, follicular atresia, corpus luteum function and luteolysis. OS-mediated precipitation of pathologies in the female reproductive tract is similar to those involved in male infertility. OS influences the oocyte and embryo quality and thus the fertilization rates. ROS appears to play a significant role in the modulation of gamete interaction and also for successful fertilization to take place. ROS in culture media may impact post-fertilization development, i.e. cleavage rate, blastocyst yield and quality (indicators of assisted reproduction outcomes). OS is reported to affect both natural and assisted fertility. Antioxidant strategies should be able to intercept both extracellular and intracellular ROS. This review discusses the sources of ROS in media used in IVF-embryo transfer and strategies to overcome OS in oocyte in-vitro maturation, in-vitro culture and sperm preparation techniques.

Abstract Oxidative stress (OS), a state characterized by an imbalance between pro-oxidant molecules including reactive oxygen and nitrogen species, and antioxidant defenses, has been identified to play a key role in the pathogenesis of subfertility in both males and females. The adverse effects of OS on sperm quality and functions have been well documented. In females, on the other hand, the impact of OS on oocytes and reproductive functions remains unclear. This imbalance between pro-oxidants and antioxidants can lead to a number of reproductive diseases such as endometriosis, polycystic ovary syndrome (PCOS), and unexplained infertility. Pregnancy complications such as spontaneous abortion, recurrent pregnancy loss, and preeclampsia, can also develop in response to OS. Studies have shown that extremes of body weight and lifestyle factors such as cigarette smoking, alcohol use, and recreational drug use can promote excess free radical production, which could affect fertility. Exposures to environmental pollutants are of increasing concern, as they too have been found to trigger oxidative states, possibly contributing to female infertility. This article will review the currently available literature on the roles of reactive species and OS in both normal and abnormal reproductive physiological processes. Antioxidant supplementation may be effective in controlling the production of ROS and continues to be explored as a potential strategy to overcome reproductive disorders associated with infertility. However, investigations conducted to date have been through animal or in vitro studies, which have produced largely conflicting results. The impact of OS on assisted reproductive techniques (ART) will be addressed, in addition to the possible benefits of antioxidant supplementation of ART culture media to increase the likelihood for ART success. Future randomized controlled clinical trials on humans are necessary to elucidate the precise mechanisms through which OS affects female reproductive abilities, and will facilitate further explorations of the possible benefits of antioxidants to treat infertility.

Oxidative stress is pre‐empted by an adequate level of antioxidants, which scavenge oxidants when they are produced in excess by different sources, including leukocytes and immature spermatozoa. Enzymatic antioxidants, such as superoxide dismutase, catalase and glutathione peroxidase, and several non‐enzymatic antioxidants (proteins, vitamins and minerals), working as oxidant scavengers and cofactors of enzymatic antioxidants have been identified in seminal plasma. The total antioxidant capacity (TAC) is a diagnostic test that can be utilised in the male infertility workup. TAC measures the amount of total antioxidants in seminal plasma. Therefore, it provides an assessment of the reductive potential in seminal plasma. Several studies have investigated the diagnostic application of TAC in various andrology conditions. There is substantial evidence in the literature to show that infertile patients have lower seminal TAC in comparison with fertile men. Moreover, there is a positive correlation between TAC and seminal parameters, such as sperm concentration, motility and morphology. Evaluation of TAC together with reactive oxygen species (ROS) and sperm DNA fragmentation index (DFI) may be beneficial in the diagnosis of male infertility. [ABSTRACT FROM AUTHOR]

Objective: To assess the effect of ejaculatory abstinence (EA) periods on routine and advanced sperm tests.Methods: Men with normozoospermia provided semen samples after 1, 2, 5, 7, 9, and 11 days of abstinence. A standard semen analysis was performed on all samples. Each specimen was assessed for levels of reactive oxygen species (ROS) and sperm DNA fragmentation. Comparison was also made by grouping EA periods into short (1 day), recommended by World Health Organization (WHO) (2-7 days), and long (9-11 days).Results: Semen volume (P < .001), sperm concentration (P < .001), and total sperm count (P < .001) increased significantly with abstinence length. Sperm DNA fragmentation was associated with the length of EA (P < .001). Both 1 and 2 days of EA had the least amount of DNA fragmentation (P < .001). Significant increase was seen in volume, pH, viscosity, total count, total motile sperm, and DNA fragmentation between short and recommended EA (P < .05), and between recommended and long EA (P < .05). Short EA had no detrimental impact on semen characteristics according to the 2010 WHO thresholds.Conclusion: Shortening of EA time is not detrimental to sperm quality in men with normozoospermia and is proposed as a method for reducing sperm DNA fragmentation. This strategy could help optimize sperm quality and the chances of natural and assisted conception. Accurate abstinence time should be considered when managing men with infertility problems with semen analyses even when it is within the recommended range. [ABSTRACT FROM AUTHOR]

In the efforts aimed at improving the quality of in-vitro-matured human oocytes, the dynamic balance and roles of pro-/antioxidants merit further consideration. In-vitro maturation (IVM) is emerging as a popular technology at the forefront of fertility treatment and preservation. However, standard in-vitro culture conditions exert oxidative stress or an imbalance between oxidants and antioxidants. Reactive oxygen species (ROS) are oxygen-derived molecules formed as intermediary products of cellular metabolism. By acting as powerful oxidants, ROS can oxidatively modify any molecule, resulting in structural and functional alterations. ROS are neutralized by an elaborate defence system consisting of enzymatic and non-enzymatic antioxidants. This review captures the inherent and external factors that may modulate the oxidative stress status of oocytes. It discusses the suspected impacts of oxidative stress on the gamut of events associated with IVM, including prematuration arrest, meiotic progression, chromosomal segregation, cytoskeletal architecture and gene expression. In-vivo and in-vitro strategies that may overcome the potential influences of oxidative stress on oocyte IVM are presented. Future studies profiling the oxidative stress status of the oocyte may permit not only the formulation of a superior IVM medium that maintains an adequate pro-/antioxidant balance, but also the identification of predictors of oocyte quality. [ABSTRACT FROM AUTHOR]

Endometriosis is a chronic pleomorphic disorder with pelvic or systemic manifestations, and is characterized by the presence of endometrial glands and stroma. In the United States, the prevalence of the disease is estimated to range from 2 to 50% in women of reproductive age. No single theory can explain the histogenesis and the pleomorphic manifestations of endometriosis. Endometriosis is being reported in younger age women and manifesting with increasing severity, hence the need to understand the role of oxidative stress (OS) in endometriosis. The presence of elevated concentrations of free radicals and lowered antioxidant potential leads to OS. The development of OS in the local peritoneal environment may be one of the links in the chain of events leading to endometriosis. Redox levels may modulate the severity and the dynamics of endometriosis and progression of the disease. OS has been implicated in infertility associated with endometriosis. Recent literature reviewed investigates the role of molecular mechanisms and genetic pathways that may modulate cellular response to OS. Antioxidant supplementation, immunomodulators, and selective progesterone receptor modulators with antioxidant effects have been investigated as possible treatments for endometriosis, but compelling evidence on the benefits of the various modalities is lacking. Results of the limited number of animal and human trials need to be corroborated by larger randomized controlled trials. [ABSTRACT FROM AUTHOR]