***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE To examine the effects of increased sperm DNA damage in relation to seminal oxidative stress in men with idiopathic and male factor infertility . Prospect i ve study . SETTING S Infertility clinic at a tertiary care academic institution . PATIENT(S ) Ninety-two infertile men with normal female partners . Sixteen fertile donors served as the control group . INTERVENTION(S ) St and ard semen analysis and assessment of levels of seminal oxidative stress . Assisted reproductive techniques in 33 of the 92 patients ( IUI [ n = 19 ] , IVF [ n = 10 ] , and intracytoplasmic sperm injection [ n = 4 ] ) . MAIN OUTCOME MEASURE(S ) Sperm DNA damage by sperm chromatin structure assay . Results were expressed as DNA fragmentation index . RESULT ( S ) Patients were classified as having either idiopathic ( n = 23 ) or male factor infertility ( n = 69 ) . Patients with idiopathic and male factor infertility had significantly higher DNA fragmentation index and oxidative stress compared with the case of fertile donors . A clinical pregnancy was achieved in 9 ( 27 % ) of 33 patients with assisted reproductive techniques . Significantly higher DNA fragmentation index and oxidative stress were found in men who failed to initiate a pregnancy after assisted reproductive techniques ( n = 24 ) , compared with the cases of those who succeeded and of the fertile donors . DNA fragmentation index was correlated positively with oxidative stress ( r = 0.27 ) , and negatively with fertilization ( r = -0.70 ) and embryo quality ( r = -0.70 ) . CONCLUSION ( S ) Sperm DNA damage is significantly increased in men with idiopathic and male factor infertility and in men who failed to initiate a pregnancy after assisted reproductive techniques . Such an increase may be related to high levels of seminal oxidative stress OBJECTIVE To determine the level of DNA damage , both fragmentation and oxidative , in the sperm population used for  intrauterine insemination ( IUI ) and intracytoplasmic sperm injection ( ICSI )  and its impact on fertilization and clinical pregnancy rates . DESIGN A prospect i ve clinical study . SETTING A tertiary care fertility clinic . PATIENT(S ) Couples undergoing ICSI ( n = 48 ) and couples undergoing IUI cycles ( n = 53 ) . INTERVENTION(S ) Assessment of both sperm DNA fragmentation using the  TUNEL assay  and oxidative DNA damage using the biomarker 8-hydroxy-2'-deoxyguanosine ( 8-OHdG ) in the sample s prepared and used for insemination . MAIN OUTCOME MEASURE(S ) Achievement of a clinical pregnancy . RESULT ( S ) Sperm DNA fragmentation and 8-OHdG were highly correlated ( r = 0.55 ) and 8-OHdG was significantly lower in those who achieved a clinical pregnancy after IUI ( 8.9 % vs. 20.2 % ) . A threshold value of 11.5 % 8-OHdG was identified as a useful predictor of IUI success . No differences were found in sperm DNA fragmentation or 8-OHdG between pregnant and nonpregnant couples in ICSI cycles . CONCLUSION ( S ) 8-Hydroxy-2'-deoxyguanosine , a biomarker of oxidative DNA damage highly correlated with sperm DNA fragmentation , in human sperm DNA has significant value in predicting the chance of a clinical pregnancy after IUI but not ICSI in assisted reproductive technology A prospect i ve study was performed to assess the impact of sperm DNA fragmentation on the outcome of IVF with own or donated oocytes . The study population included 178 couples ( 62 cycles of IVF , 116 of intracytoplasmic sperm injection ( ICSI ) ) with own ( n=77 ) and donor ( n=101 ) oocytes .  DNA fragmentation was evaluated by TdT ( terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling assay . Correlation between DNA damage to oocyte fertilization , embryo quality and clinical pregnancy , implantation and miscarriage rates was evaluated . DNA fragmentation was not related to fertilization rates in either IVF ( r=0.08 ) or ICSI ( r=-0.04 ) cycles . DNA fragmentation was similar in patients with < 50 % embryo utilization rate compared with ≥50 % , in cancelled and in embryo transfer cycles and in miscarriages and in successful deliveries . Moreover , DNA fragmentation was similar in pregnant and non-pregnant women as well as in IVF with own or donor oocytes . In the multivariable analysis , the odds ratio of DNA after controlling by age was 1.0 . Using a 36 % sperm fragmentation threshold , results did not vary . It is concluded that DNA damage was not related to outcomes of IVF or ICSI with own or donor oocytes OBJECTIVE To examine sperm DNA fragmentation in semen used for assisted reproduction procedures to establish this factor 's prognostic role in fertilization rate , embryo development , pregnancy rate , and outcome . DESIGN Prospect i ve study . SETTING Department of Medicine and Biology of Reproduction of the Edouard Herriot Hospital in Lyon , France . PATIENT(S ) 322 couples , divided into 88 cycles of in vitro fertilization ( IVF ) or 234 cycles of intracytoplasmic sperm injection ( ICSI ) .  INTERVENTION(S ) Sperm DNA fragmentation was detected in sperm obtained 2 to 5 months before the ART procedure . MAIN OUTCOME MEASURE(S ) Sperm DNA fragmentation was measured with the  terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling ( TUNEL ) technique .  RESULT ( S ) There was a negative statistical correlation between the rate of fragmentation and the semen characteristics . A statistically significant negative relationship was found for sperm DNA fragmentation and fertilization when ICSI and IVF were compared . With ICSI , a statistically significant negative relationship was found between fertilization rate and percentage of sperm DNA fragmentation ( DNA fragmentation index , or DFI ) . The risk of nontransfer due to blocked embryo development increased when the DFI exceeded 15 % ( 18.2 % for ICSI vs 4.2 % for IVF ) with an odds ratio of 5.05 . The miscarriage risk increased fourfold when the DFI exceeded 15 % ( 37.5 % for ICSI vs 8.8 % for IVF ) . CONCLUSION ( S ) Sperm DNA fragmentation measured 2 to 5 months before the assisted reproduction procedure was a prognostic indicator of the fertilization , pregnancy , and miscarriage rates and the pregnancy outcome Background Sperm DNA damage is associated with male infertility but whether normozoospermic infertile men also have DNA damage is unknown . Objective To evaluate sperm DNA and chromatin integrity in men with mild male factor infertility . Design , setting and participants Prospect i ve study of 102 consecutive men ( 78 normozoospermic , 15 asthenozoospermic , 9 oligozoospermic ) enrolled for intrauterine insemination ( IUI ) and 15 fertile controls .  Outcome measurements and statistical analysis St and ard semen parameters and sperm chromatin and DNA integrity were assessed and compared between groups . Sperm chromatin quality was assessed by ( 1 ) aniline blue staining ( AB is specific to histone lysines ) , ( 2 ) iodoacetamide fluorescein fluorescence ( IAF targets free protamine sulfhydryl groups ) and ( 3 ) sperm chromatin structure  assay ( SCSA ) with the results expressed as % DNA fragmentation index ( % DFI ) . Results and limitations The mean ( ±SD ) percentage of spermatozoa with positive IAF fluorescence was significantly higher in the IUI population compared to fertile controls ( 17 % ± 10 % vs. 8 % ± 6 % , P = 0.0011 ) and also in the normozoospermic subset ( n = 78 ) compared to controls ( 16 % ± 9 % vs. 8 % ± 6 % , P < 0.0001 , ANOVA ) . We also observed a trend toward lower % progressive motility , and higher % AB staining and % DFI in the IUI group compared to controls . We observed significant relationships between sperm % DFI and progressive motility ( r = −0.40 , P < 0.0001 ) and between positive AB staining and IAF fluorescence ( r = 0.58 , P < 0.0001 ) . Conclusions The data indicate that sperm chromatin integrity may be abnormal in men enrolled in IUI treatment cycles , despite the fact that most of these men are normozoospermic BACKGROUND We aim ed to investigate whether sperm DNA quality may predict intrauterine insemination ( IUI ) outcome . METHODS The study was design ed in a prospect i ve cohort fashion , at a tertiary centre for reproductive medicine . A total of 119 patients underwent 154 cycles of IUI .  Parameters related to demography , cycle management and semen sample used for IUI were evaluated . Conventional semen parameters , morphology ( strict criteria ) , sperm DNA fragmentation and stability [ evaluated by terminal deoxynucleotidyl transferase-mediated dUDP nick-end labelling ( TUNEL ) and acridine orange staining under both acid and acid + heat denaturing conditions respectively ] were measured . The main outcome measure was clinical pregnancy , defined as ultrasonographic visualization of intrauterine gestational sac(s ) . RESULTS Logistic regression analyses were done on six sets of data , including all cycles combined , cycles with washed sample s , first cycle of each couple , first cycle of each couple with washed sample s , cycles stimulated with gonadotrophins and finally gonadotrophin-stimulated cycles with washed sample s. The number of pre-ovulatory follicles on day of hCG , the age of the woman and the percentage of sperm with acid- + heat-resistant DNA were the parameters that predicted IUI outcome in most of these data subsets . For the gonadotrophin-stimulated cycles , age of the man appeared as a predictor as opposed to that of the woman ; and for the cycles within this subgroup , where the semen sample was washed , sperm DNA fragmentation and age of the man were the only two parameters to predict IUI outcome . No sample s with > 12 % of sperm having DNA fragmentation result ed in pregnancy . CONCLUSIONS The number of follicles , age of the woman/man and sperm DNA quality may predict IUI outcome OBJECTIVES To st and ardize the TUNEL assay by establishing inter- and intraobserver variability , interassay variability , cutoff values , sensitivity and specificity of the assay , and study ing the distribution of the DNA damage in a population of infertile men referred to a clinical and rology laboratory . METHODS Seminal ejaculates from 25 healthy male volunteers ( controls ) and 194 infertile men ( with male factor infertility ) referred to an and rology laboratory were examined for DNA damage by TUNEL assay using flow cytometric analysis . RESULTS Both the inter- and intraobserver variability and interassay variability was small ( < 10 % ) . DNA damage in the controls was 11.9 ± 6.8 % vs. 29.5 ± 18.7 % in patients ( P < .001 ) . The cut-off value of 19.25 % maximized the observed sensitivity ( 64.9 % ) and specificity ( 100 % ) of the assay . The distribution of DNA damage in the patients was as follows : 14.9 % ( 29 of 194 ) with DNA damage between 0 % and 10 % ; 22.7 % ( 44 of 194 ) between 10 % and 20 % ; 8.8 % ( 17 of 194 ) between 20 % and 30 % ; and 17.5 % ( 34 of 194 ) between 30 % and 40 % . Finally , 27.3 % ( 53 of 194 ) had TUNEL values > 40 % . CONCLUSIONS We report a detailed st and ardization of the TUNEL assay for clinical use , as well as reference ranges for DNA damage in normal healthy donors and infertile men . A cut-off of 19.25 % with observed 100 % specificity established in our program can differentiate infertile men with DNA damage from healthy men . This test can be offered to infertile patients who are idiopathic , have severe oxidative stress-related abnormal semen quality , and contribute to the infertility problem of the couple who are considering assisted reproductive techniques BACKGROUND St and ard semen parameters have proven poor at predicting the outcomes of IVF treatment cycles . As recent studies suggest that the male genome may play an important role in early embryogenesis , this study attempts to correlate the level of sperm DNA damage in fresh semen and prepared sperm with the outcomes of conventional IVF treatment cycles . METHODS Forty patients embarking on IVF treatment were recruited into this prospect i ve observational study . Both fresh semen and PureSperm-prepared sperm were processed using a modified comet assay 3 - 6 months prior to the patients ' IVF treatment cycles . Comet head DNA ( mean and integrated head density ) and tail DNA parameters ( length and moment ) were measured separately . RESULTS Significant correlations between total sperm concentration and between comet length , moment , mean head density with embryo quality were detected in fresh semen and prepared sperm . Surprisingly , no significant correlations between head and tail parameters were detected . CONCLUSIONS Comet head and tail DNA parameters appear to be potentially useful as predictors of 
    Output:
    
There is sufficient evidence in the existing literature suggesting that sperm DNA damage has a negative effect on clinical pregnancy following IVF and /or ICSI treatment