Reactive oxygen species as an independent marker of male factor infertility.

OBJECTIVE: To determine the abnormal patterns of reactive oxygen species (ROS) production in male factor infertility (MFI) patients and to define the ROS reference values in such patients. DESIGN: A retrospective study. SETTING: Male infertility clinic at a tertiary healthcare center. PATIENT(S): We examined 132 MFI patients (all normal sperm parameters, n = 24, and all abnormal sperm parameters, n = 38) and 34 healthy donors. INTERVENTION(S): Routine semen analysis, measurement of ROS. MAIN OUTCOME MEASURE(S): Sperm parameters, ROS levels (10(4) cpm/20 x 10(6) sperm). RESULT(S): Normal, healthy donors had significantly higher (P<.0001) sperm concentration, motility, and morphology compared with all MFI patients. Univariate analysis indicated a significant association between MFI and log (ROS + 1) (odds ratio [OR] = 3.84), besides sperm parameters and age. A multivariate model using logistic regression analysis also indicated an independent association of log ROS with MFI (OR = 4.25). The ROS cutoff values of 1.2-1.4 had a sensitivity of 0.70-0.78 with a corresponding specificity of 0.82. However, at a cutoff point of 1.2, the OR was 68.6, which increased with an increase in the cutoff. CONCLUSION(S): High ROS is an independent marker of MFI, irrespective of whether these patients have normal or abnormal semen parameters. We suggest the inclusion of ROS measurement as part of idiopathic infertility evaluation. Treatment with antioxidants may be beneficial in such patients.

Significance of sperm characteristics in the evaluation of male infertility.

OBJECTIVE: To compare sperm characteristics among: patients undergoing infertility evaluation, patients with male factor infertility (MFI), healthy sperm donors, and men with proven fertility; to examine the overlap of sperm characteristics in all four of these groups; and to identify good discriminators of fertility versus infertility among sperm characteristics. DESIGN: Retrospective study. SETTING: Male infertility clinic at a tertiary care hospital. PATIENT(S): Proven fertile men (n = 56), normal donors (n = 91), men presenting for infertility evaluation (n = 406), and MFI patients (n = 166). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Routine semen analysis. RESULT(S): Using current World Health Organization (WHO) reference values, a large group of MFI patients presented with higher sperm concentration (27.5 x 10(6) to 99.2 x 10(6)), resulting in broader overlap with fertile men and poor sensitivity (0.48). Similarly, percentage normal morphology (%) using Tygerberg's strict criteria was low in most of the MFI patients (sensitivity 0.83), almost half of the fertile men also presented with abnormal morphology (specificity 0.51). Of all the variables examined, sperm motility (%) was superior, having minimum overlap range (lower and upper cut-off values 46% and 75%) and high sensitivity (0.74) and specificity (0.90). Areas under curve were higher for motility (0.90) and concentration (0.84) compared with morphology (WHO 0.65 and Tygerberg's strict criteria 0.74). CONCLUSION(S): Sperm motility and concentration provide more accurate information than morphology (WHO and Tygerberg's criteria) during infertility evaluation. Redefining the reference values for concentration and morphology may significantly increase the importance of routine semen analysis.

Relationship between epidemiological features and aetiology of male infertility as diagnosed by a comprehensive infertility service provider.

This study examined the relationship between demographic features and aetiological causes of male infertility. Primary infertility was the presentation in 78% of patients. The incidence of varicocele was the highest (31%), whereas only 4.6% had vasectomy reversal and 7.4% of men were diagnosed with idiopathic infertility. Using the chi-squared test, there was no significant difference in the incidence of different causes of infertility among different ethnic groups (White, African-American, Asian, Hispanic, and other). Furthermore, there was no increased incidence of infertility aetiology with any particular occupation, race, religion, smoking or alcohol intake. In this study population, there was no association between the various risk factors (occupation, smoking, alcohol intake, and race) and the aetiologies of infertility. The proportion of patients diagnosed with idiopathic infertility was significantly less than reported in the literature.

Identification of male factor infertility using a novel semen quality score and reactive oxygen species levels.

PURPOSE: To determine whether patients with male factor infertility can be accurately identified by calculating a novel semen quality score and measuring levels of reactive oxygen species during routine infertility screening. METHODS: Semen samples from 133 patients and 91 healthy donors were evaluated with manual and computer-assisted semen analysis. A principal component analysis model was employed to calculate a semen quality score. In brief, this score was calculated by base 10 logarithms multiplied by varying weights given to 9 sperm parameters. Reactive oxygen species levels were measured using chemiluminescence assay. RESULTS: The semen quality score had a sensitivity of 80.45% and accuracy of 77% at a cutoff of 93.1 in identifying patients with male factor infertility. The area under the receiver operating characteristic curves for the semen quality score was 84.28% (95% CI: 65.22%-100%). Reactive oxygen species levels [log10 (reactive oxygen species +1)] were significantly higher in male factor infertility patients. Reactive oxygen species had a sensitivity of 83.47% and specificity of 60.52% with an accuracy of 75% at a cutoff of 1.25 in identifying male factor infertility patients. The area under the receiver operating characteristic curve for reactive oxygen species levels was 78.92% (95% CI: 72.60%-85.23%). Semen quality scores were significantly and negatively correlated with reactive oxygen species levels in the donors and the male factor infertility patients. CONCLUSIONS: The semen quality score and reactive oxygen species levels in semen samples appear to be strongly associated with male factor infertility. Because both of these parameters are more sensitive than individual sperm parameters in identifying male factor infertility, they should be included in routine infertility screening.

Identification of male factor infertility using a novel semen quality score and reactive oxygen species levels

OBJETIVO: Determinar se pacientes portadores do fator de infertilidade masculina podem ser precisamente identificados através do cálculo de um novo escore de qualidade de sêmen e pela medida de espécies reativas de oxigênio durante uma avaliação rotineira de infertilidade. MÉTODOS: Amostras de sêmen de 133 pacientes e de 91 doadores saudáveis foram avaliadas através de análise manual e computadorizada de sêmen. Um modelo de análise do componente principal foi empregado para calcular o escore de qualidade de sêmen, utilizando logaritmos base 10, multiplicados por ponderações variáveis de 9 parâmetros espermáticos. Os níveis de espécies reativas de oxigênio foram medidos através de testes de quimiluminescência. RESULTADOS: O escore de qualidade de sêmen apresentou sensibilidade de 80.45% e precisão de 77% para um "cutoff" de 93.1 na identificação do fator de infertilidade masculina. A área sob a curva "receiver operating characteristic" para o escore de qualidade de sêmen foi de 84.28% (95% intervalo de confiança: 65.22%-100%). Os níveis de espécies reativas de oxigênio [log10 (espécies reativas de oxigênio +1)] foram siginificativamente mais elevados nos pacientes portadores de fator de infertilidade masculina. A medica de espécies reativas de oxigênio apresentou sensibilidade de 83.47% e especificidade de 60.52% com uma precisão (definida como pacientes portadores do fator de infertilidade masculina com diagnóstico positivo e doadores corretamente excluídos) de 75% para um "cutoff" de 1.25 na identificação de pacientes portadores do fator de infertilidade masculina. A área sob a curva "receiver operating characteristic" para níveis de espécies reativas de oxigênio foi de 78.92% (95% intervalo de confiança: 72.60%-85.23%). Os escores de qualidade de sêmen correlacionaram negativamente com os níveis de espécies reativas de oxigênio tanto nos doadores e nos pacientes portadores do fator de infertilidade masculina. CONCLUSÕES: O escore de qualidade de sêmen e os níveis espécies reativas de oxigênio nas amostras de sêmen parecem associar-se fortemente com o fator de infertilidade masculina. Na medida em que os dois parâmetros mostraram-se mais sensíveis que parâmetros espermáticos individuais na identificação do fator de infertilidade masculina, deveriam ser incluídos na avaliação rotineira de infertilidade.

Correlation of reactive oxygen species levels with the fertilization rate after in vitro fertilization: a qualified meta-analysis.

Our meta-analysis analyzed the relationship between levels of reactive oxygen species (ROS) and fertilization rate after in vitro fertilization (IVF), and showed a statistically significant correlation between the ROS levels and the IVF fertilization rate (estimated overall correlation -0.374 [95% CI, -0.520, -0.205]). We conclude that ROS has a statistically significant effect on the fertilization rate after IVF, and that the measurement of ROS levels in semen specimens before IVF may be useful in predicting the IVF outcome and in counseling patients.

Characterization of oxidative stress status by evaluation of reactive oxygen species levels in whole semen and isolated spermatozoa.

We defined the basal levels of reactive oxygen species (ROS) in normal donors in neat (whole unprocessed) semen specimens, and in mature and immature spermatozoa isolated by a double-density gradient technique. In addition, we demonstrated that the ROS levels were significantly lower in neat semen compared with washed spermatozoa. The reference values of ROS in neat semen and mature spermatozoa can be used to define the pathologic levels of ROS in infertile men and may guide in therapeutic interventions.

Relationship of interleukin-6 with semen characteristics and oxidative stress in patients with varicocele.

OBJECTIVES: To examine levels of interleukin-6 (IL-6) in fertile semen donors and patients with varicocele and examine its association with semen characteristics and levels of reactive oxygen species (ROS). METHODS: We conducted a prospective study consisting of 15 fertile donors (controls) and 35 infertile patients with varicocele. Semen analysis was performed according to the World Health Organization guidelines. IL-6 levels were measured using the enzyme-linked immunosorbent assay. ROS (x10(4) counted photons per minute per 20 x 10(6) sperm) and total antioxidant capacity (molar trolox equivalents) were measured using a chemiluminescence assay. RESULTS: The sperm concentration and motility were significantly greater in the donors compared with the infertile patients with varicocele (P <0.0001 and P = 0.01, respectively). The IL-6 (log10 [IL-6 +1]) and ROS (log10 [ROS +1]) levels were significantly greater in infertile patients with varicocele than in the donors (IL-6: 2.1 [1.7, 2.4] versus 0.7 [0, 1.9], P = 0.003; ROS: 1.8 [1.2, 2.6] versus 1.0 [0.7, 1.6], P = 0.04). The total antioxidant capacity levels were significantly lower in the varicocele patients (1166.7 +/- 366.2) than in the donors (1556.4 +/- 468.1; P = 0.003). The IL-6 levels correlated significantly with the ROS levels in the infertile patients with varicocele (r = -0.39; P = 0.01). CONCLUSIONS: Infertile patients with varicocele exhibited elevated levels of IL-6 and ROS and decreased levels of total antioxidant capacity. Pro-inflammatory cytokine IL-6 and oxidative stress may play a role in the pathophysiology of infertility in these patients.

Cryopreservation of human spermatozoa: comparison of two cryopreservation methods and three cryoprotectants.

OBJECTIVE: To evaluate the ability of two cryopreservation methods and three cryoprotectants to preserve sperm quality. DESIGN: A prospective clinical study. SETTING: Male infertility clinic at a tertiary healthcare center. PATIENT(S): Twenty infertile men and 10 healthy donors. INTERVENTION(S): In the first experiment, semen was cryopreserved by either the Irvine Scientific method (IS) or the Cleveland Clinic Foundation (CCF) method. In the second experiment, semen was cryopreserved by the IS method and one of three cryoprotectants: TES and Tris yolk buffer, Sperm Freezing Medium, or Enhance Sperm Freeze. MAIN OUTCOME MEASURE(S): Postthaw sperm motility, cryosurvival, and kinematics. RESULT(S): Percentages of postthaw sperm motility and cryosurvival were higher in the IS cryopreservation method compared with in the CCF method (15.94 +/- 9.19 vs. 12.07 +/- 7.31 and 47.42 +/- 17.44 vs. 35.76 +/- 17.56). However, the CCF method resulted in significantly better sperm kinematics. Postthaw motility in the donors and patients was highest in the samples frozen in TES and Tris yolk buffer medium. CONCLUSION(S): The IS method was associated with more flash freezing compared with the CCF method and resulted in better preservation of sperm motility and a higher cryosurvival rate. TES and Tris yolk buffer was most effective at protecting sperm from the negative effects of the cryopreservation process. This may be due to the presence of egg yolk along with glycerol.

Inter-sample variability in post-thaw human spermatozoa.

Semen cryopreservation is a useful tool for preserving fertility in men who have been diagnosed with cancer and will undergo chemotherapy, radiotherapy or testicular surgery. Semen is also commonly cryopreserved prior to its use in assisted reproductive techniques such as in vitro fertilization and intracytoplasmic sperm injection. The post-thaw quality of banked sperm can vary, which may negatively affect fertilization rates. The objective of our study was to assess the pre-freeze and post-thaw variability of sperm parameters in patients who used our sperm banking services. Multiple samples obtained after a short period of sexual abstinence were examined for variation in sperm characteristics. Semen samples showed a high degree of post-thaw inter-sample variability in sperm motility, motion characteristics, and percentage cryosurvival rate compared with the pre-freeze inter-sample variability. Further research is necessary to understand the mechanism(s) responsible for this variability. This may also assist clinicians utilize semen samples with optimum semen quality in ART procedures.

Role of antioxidants in treatment of male infertility: an overview of the literature.

Seminal oxidative stress in the male reproductive tract is known to result in peroxidative damage of the sperm plasma membrane and loss of its DNA integrity. Normally, a balance exists between concentrations of reactive oxygen species and antioxidant scavenging systems. One of the rational strategies to counteract the oxidative stress is to increase the scavenging capacity of seminal plasma. Numerous studies have evaluated the efficacy of antioxidants in male infertility. In this review, the results of different studies conducted have been analysed, and the evidence available to date is provided. It was found that although many clinical trials have demonstrated the beneficial effects of antioxidants in selected cases of male infertility, some studies failed to demonstrate the same benefit. The majority of the studies suffer from a lack of placebo-controlled, double-blind design, making it difficult to reach a definite conclusion. In addition, investigators have used different antioxidants in different combinations and dosages for varying durations. Pregnancy, the most relevant outcome parameter of fertility, was reported in only a few studies. Most studies failed to examine the effect of antioxidants on a specific group of infertile patients with high oxidative stress. Multicentre, double-blind studies with statistically accepted sample size are still needed to provide conclusive evidence on the benefit of antioxidants as a treatment modality for patients with male infertility.