***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: The objective of this study was to examine different clinical scenarios of in-vitro conception , viz . fertilization with conventional IVF , IVF with high insemination concentration ( HIC ) and intracytoplasmic sperm injection ( ICSI ) , and assess on a sibling oocyte comparison the hypothesis that ICSI should be performed in all cases requiring in-vitro conception . ICSI with husb and 's spermatozoa had a higher incidence of fertilization as compared with IVF or IVF with HIC with donor spermatozoa ( if previous failure of fertilization had occurred ) for unexplained infertility . Similarly , ICSI with husb and 's spermatozoa had as high an incidence of fertilization as IVF with donor spermatozoa for patients with severe oligozoospermia , asthenozoospermia and /or teratozoospermia , even when the spermatozoa were not selected for their morphology . Two studies were performed to assess ICSI in potential oocyte-related failure of IVF , viz . when fertilization occurred in > 50 % of oocytes for one group of patients , and in < 50 % of oocytes in a second group . In both of these studies a significant proportion of the oocytes that failed to fertilize with conventional IVF eventually fertilized after ICSI . The overall conclusion was that ICSI as a first option offers a higher incidence of fertilization , maximizes the number of embryos and minimizes the risk of complete failure of fertilization for all cases requiring in-vitro conception . However , among other concerns , current knowledge of ICSI as an outcome procedure does not provide the confidence to use this process in all cases of IVF for the time being BACKGROUND The evidence underpinning the timing of an oocyte collection in  IVF or ICSI  is limited . The aim of this study was to assess the effect of the follicle diameter size of the dominant follicle on ongoing pregnancy rates . METHODS We conducted a r and omized controlled trial , including women aged between 18 and 43 years who were scheduled for GnRH agonist down-regulated IVF/ICSI treatment in four assisted conception units . Women were r and omized between timing oocyte collection when the leading follicle had a diameter of 22 mm or when the leading follicle had a diameter of 18 mm . The primary end-point was ongoing pregnancy , defined as a viable pregnancy at 12 weeks of gestation . RESULTS The trial had major problems with recruiting patients and after the planned 2 years of recruiting only half of the aim ed 400 inclusion s were obtained . We allocated 97 women to the 22-mm group and 93 women to the 18-mm group . In the 22-mm group more women reached an ongoing pregnancy ( 37 of 97 women , 38 % ) compared with the 18-mm group ( 22 of 93 women , 24 % ) result ing in a relative risk of 1.6 [ 95 % confidence interval ( CI ) : 1.03 - 2.5 ] . In a logistic regression analysis , the timing of oocyte collection , adjusted for female age , IVF/ICSI and centre , was still associated with ongoing pregnancy , although the association was no longer statistically significant ( OR : 2.0 ; 95 % CI : 0.96 - 4.2 ) CONCLUSIONS : This study suggests that delaying the timing of oocyte collection in IVF or ICSI results in better ongoing pregnancy rates , however , larger studies have to be performed to prove or refute these findings . TRIAL REGISTRATION IS RCT N24724622 OBJECTIVE To determine whether a crossover design results in a different estimate of treatment effect compared with a parallel design . DESIGN With the aid of a computer program , data sets of subfertile patients were simulated under different assumptions . These patients were subjected to 2 treatments that were compared in either a parallel- design or a crossover- design trial . Results were analyzed using logistic regression . SETTING University hospital . PATIENT(S ) Simulated patients of a heterogeneous subfertile population . INTERVENTION(S ) Two treatment modalities with a pregnancy rate of 10 % and of 20 % in the first cycle were offered for 6 cycles to simulated heterogeneous population s. MAIN OUTCOME MEASURE(S ) After 1,000 simulations for each assumption , median pregnancy rates and odds ratios were compared between the crossover- and parallel- design trials . RESULT ( S ) No relevant difference in estimated treatment effect was found between the design s. The crossover design result ed in more pregnancies overall than the parallel design . CONCLUSION ( S ) In infertility research , parallel and crossover design s will lead to about the same results . Although the crossover design showed a slight tendency to overestimate the treatment effect of the most effective treatment , this overestimation is clinical ly not relevant and is small in relation to the r and om error . Because of its practical advantages and because more pregnancies are achieved , a crossover design should be the first choice in infertility research Objectives To compare the effectiveness of in vitro fertilisation with single embryo transfer or in vitro fertilisation in a modified natural cycle with that of intrauterine insemination with controlled ovarian hyperstimulation in terms of a healthy child . Design Multicentre , open label , three arm , parallel group , r and omised controlled non-inferiority trial . Setting 17 centres in the Netherl and s. Participants Couples seeking fertility treatment after at least 12 months of unprotected intercourse , with the female partner aged between 18 and 38 years , an unfavourable prognosis for natural conception , and a diagnosis of unexplained or mild male subfertility . Interventions Three cycles of in vitro fertilisation with single embryo transfer ( plus subsequent cryocycles ) , six cycles of in vitro fertilisation in a modified natural cycle , or six cycles of intrauterine insemination with ovarian hyperstimulation within 12 months after r and omisation . Main outcome measures The primary outcome was birth of a healthy child result ing from a singleton pregnancy conceived within 12 months after r and omisation . Secondary outcomes were live birth , clinical pregnancy , ongoing pregnancy , multiple pregnancy , time to pregnancy , complications of pregnancy , and neonatal morbidity and mortality Results 602 couples were r and omly assigned between January 2009 and February 2012 ; 201 were allocated to in vitro fertilisation with single embryo transfer  , 194 to in vitro fertilisation in a modified natural cycle  , and 207 to intrauterine insemination with controlled ovarian hyperstimulation .  Birth of a healthy child occurred in 104 ( 52 % ) couples in the in vitro fertilisation with single embryo transfer group , 83 ( 43 % ) in the in vitro fertilisation in a modified natural cycle group , and 97 ( 47 % ) in the intrauterine insemination with controlled ovarian hyperstimulation group . This corresponds to a risk , relative to intrauterine insemination with ovarian hyperstimulation , of 1.10 ( 95 % confidence interval 0.91 to 1.34 ) for in vitro fertilisation with single embryo transfer and 0.91 ( 0.73 to 1.14 ) for in vitro fertilisation in a modified natural cycle . These 95 % confidence intervals do not extend below the predefined threshold of 0.69 for inferiority . Multiple pregnancy rates per ongoing pregnancy were 6 % ( 7/121 ) after in vitro fertilisation with single embryo transfer , 5 % ( 5/102 ) after in vitro fertilisation in a modified natural cycle , and 7 % ( 8/119 ) after intrauterine insemination with ovarian hyperstimulation ( one sided P=0.52 for in vitro fertilisation with single embryo transfer compared with intrauterine insemination with ovarian hyperstimulation ; one sided P=0.33 for in vitro fertilisation in a modified natural cycle compared with intrauterine insemination with controlled ovarian hyperstimulation ) . Conclusions In vitro fertilisation with single embryo transfer and in vitro fertilisation in a modified natural cycle were non-inferior to intrauterine insemination with controlled ovarian hyperstimulation in terms of the birth of a healthy child and showed comparable , low multiple pregnancy rates . Trial registration Current Controlled Trials IS RCT N52843371 ; Nederl and s Trial Register NTR939 OBJECTIVE To determine whether crossover trials with simple pooling of data over different study periods leads to a different estimate of treatment effect compared with parallel group trials in infertility research using pregnancy as the outcome measure . DESIGN An observational study using nine overviews that included trials with both crossover and parallel group design s. These overviews comprised 17 crossover and 17 parallel group trials . In total , there were 5,291 outcomes including 775 pregnancies . The association between study design and treatment effect estimate was analyzed using multiple logistic regression , controlling for differences in the therapeutic interventions and variations in the method ological quality of the trials . SETTING Infertile patients in an academic research environment . PATIENTS Infertile patients undergoing treatment efficacy evaluation in controlled trials . INTERVENTIONS R and om allocation to a variety of treatments including clomiphene citrate , hCG , IUI , tamoxifen , and bromocriptine . MAIN OUTCOME MEASURE Estimate of bias between study design s , based on the interaction of study design and treatment in the logistic regression model . RESULTS Crossover trials produced a larger average estimate of treatment effect compared with trials with a parallel group design , overestimating the odds ratio by 74 % ( 95 % confidence interval , 2 % to 197 % ) . CONCLUSION The use of a crossover design for evaluating infertility treatments with outcomes that prevent patients from completing later phases of the trial should be avoided because it leads to exaggerated estimates of treatment effect and may result in erroneous inferences and clinical decisions . Furthermore , the type of study design should be taken into account when assessing the method ological quality of therapy trials in infertility Purpose To reevaluate the effect of isolated teratozoospermia on IVF and determine if there was any therapeutic benefit to isolated teratozoospermia by ICSI , since there are no widely accepted criteria for the treatment technique about isolated teratozoospermia . Methods A total of 441 couples with > 20 million and progressive motility > 30 % sperm undergoing their first IVF/ICSI cycle were included in the study between 2008 and 2010 , for whom at least 8 oocytes were retrived . Isolated teratozoospermia was diagnosed in 183 of the included couples , and the rest couples ( normal sperm morphology ) were studied as control . Sibling oocytes were r and omized to be inseminated either by ICSI or IVF .  Fertilization rate , embryo quality , pregnancy rate , implantation rate and spontaneous abortion rate were assessed . Results There was no difference in the percentage of eggs fertilized , implantation rate , pregnancy rate and spontaneous abortion rate between conventional IVF and ICSI regardless of the percentage of normal morphology . The day 3 embryonic morphology and rate of development were not different despite the insemination method and percentage of normal morphology . Conclusion Because isolated teratozoospermia did not influence the major indices of IVF and the unnecessary use of ICSI is time-consuming , costly and potential risks , couples with isolated teratozoospermia need not be subjected to ICSI Background Multiple pregnancies are high risk pregnancies with higher chances of maternal and neonatal mortality and morbidity . In the past decades the number of multiple pregnancies has increased . This trend is partly due to the fact that women start family planning at an increased age , but also due to the increased use of ART.Couples with unexplained or mild male subfertility generally receive intrauterine insemination IUI with controlled hormonal stimulation ( IUI COH ) . The cumulative pregnancy rate is 40 % , with a 10 % multiple pregnancy rate . This study aims to reveal whether alternative treatments such as IVF elective Single Embryo Transfer ( IVF e SET ) or Modified Natural Cycle IVF ( MNC IVF ) can reduce the number of multiple pregnancy rates , but uphold similar pregnancy rates as IUI COH in couples with mild male or unexplained subfertility . Secondly , the aim is to perform a cost effective analyses and assess treatment preference of these couples . Methods / Design We plan a multicentre r and omised controlled clinical trial in the Netherl and s comparing six cycles of intra-uterine insemination with controlled ovarian hyperstimulation or six cycles of Modified Natural Cycle ( MNC ) IVF or three cycles with IVF-elective Single Embryo Transfer ( eSET ) plus cryo-cycles within a time frame of 12 months . Couples with unexplained subfertility or mild male subfertility and a poor prognosis for treatment independent pregnancy will be included . Women with anovulatory cycles , severe endometriosis , double sided tubal pathology or serious endocrine illness will be excluded . Our primary outcome is the birth of a healthy singleton . Secondary outcomes are multiple pregnancy , treatment costs , and patient experiences in each treatment arm . The analysis will be performed according tot the intention to treat principle . We will test for non-inferiority of the three arms with respect to live birth . As we accept a 12.5 % loss in pregnancy rate in one of the two IVF arms to prevent multiple pregnancies , we need 200 couples per arm ( 600 couples in total ) . Discussion Determining the safest and most cost-effective treatment will ensure optimal chances of pregnancy for subfertile couples with substantially 
    Output:
    
None of the women had OHSS.Overall , we found no evidence of a difference between any of the groups in rates of live birth , pregnancy or adverse events ( multiple pregnancy , miscarriage ) .
We found insufficient evidence to determine whether there was any difference in safety and effectiveness between different treatments for  male subfertility .