Successful Intracytoplasmic Sperm Injection Research Articles

Clinical implications of sperm DNA damage

Traditionally, the diagnosis of male infertility has relied upon microscopic assessment and biochemical assays to determine human semen quality. These tests are essential to provide the fundamental information on which clinicians base their initial diagnosis. However, none of these parameters addresses sperm function and their clinical value in predicting fertility is questionable. The advent of intracytoplasmic sperm injection (ICSI) has further reduced the significance and perceived need for sperm quality tests since ICSI requires only one sperm for the procedure to be successful. Even the conventional measures of sperm quality in terms of normal morphology or motility are not necessary for successful ICSI. Funding of andrological research has been neglected and improvement in assisted reproductive technology (ART) success has suffered as a consequence. Testing of sperm DNA damage shows much promise both as a diagnostic test for male infertility and a prognostic test for ART outcomes. It has been shown to be closely associated with numerous fertility outcomes including negative relationships with fertilization, embryo quality, implantation and positive relationships with miscarriage and childhood diseases. Here we report the relationships between in vitro fertilisation, ICSI pregnancy rates and sperm DNA damage, using the Comet assay to measure DNA fragmentation and also a novel test to measure modified bases, as a indication of oxidative DNA injury.

Sperm retrieval for azoospermia and intracytoplasmic sperm injection success rates – A personal overview

It is often questioned whether sperm parameters, including whether retrieved or ejaculated, have any effect on intracytoplasmic sperm injection (ICSI) results. Do severe spermatogenic defects affect embryo quality or pregnancy rate? Further, does it matter in azoospermic patients whether the sperm source is testicular or epididymal? Our studies show there is no significant difference in results with ICSI related to any sperm count parameters either with patient's sperm or even with donor sperm. No matter how poor the sperm count, there was no difference from patients with high sperm counts nor even patients using donor sperm. There is no significant difference between results with epididymal sperm, either fresh or frozen, in comparison to results with ejaculated or donor sperm. However, both pregnancy rate and delivery rate were considerably lower with testicular sperm (testis sperm extraction) than with epididymal sperm (microsurgical epididymal sperm aspiration). This was true for overall results as well as in each category of the female partner's age. It is obvious that in all these cycles the female partner's age was the most important determinant of delivery rate, but testicular sperm always yielded lower results than epididymal sperm. These results show that it is the origin of the sperm rather than the spermatogenic defect that determines success rate with ICSI.

DNA Fragmentation in Morphologically Normal Spermatozoa: How Much Should We Be Concerned in the ICSI Era?

Intracytoplasmic sperm injection (ICSI) has revolutionized the treatment of male infertility. However, there are still unanswered questions about the safety of this technique. During ICSI, only morphologically normal and motile spermatozoa are typically used to fertilize an oocyte. We recently reported that in infertile men, spermatozoa with apparently normal morphology may have DNA fragmentation. This finding consequently raised the possibility that spermatozoa with normal-shaped appearance but with DNA fragmentation could be mistakenly selected to fertilize oocytes during ICSI. This concern became more clinically significant following the subsequent finding that the presence of an increased proportion of normal spermatozoa with damaged DNA was negatively associated with embryo quality and pregnancy outcome after ICSI. Herein, we propose and discuss the hypothesis that the examination of DNA integrity in the subpopulation of highly motile (hence viable) and morphologically normal cells (and not in the total sperm population) may provide optimized information in prediction of ICSI success. More importantly, this new way of evaluation may provide reassurance about genomic normalcy and minimal risk of transmission of genetic disease and guide the development of improved methods of selection of spermatozoa with intact DNA to be used in assisted reproduction.

A Noninvasive, Motility Independent, Sperm Sorting Method and Technology to Identify and Retrieve Individual Viable Nonmotile Sperm for Intracytoplasmic Sperm Injection

For intracytoplasmic sperm injection in the absence of sperm motility it can be virtually impossible to distinguish viable from nonviable sperm. A reliable means to identify viable nonmotile sperm is needed and would likely improve the intracytoplasmic sperm injection success rate. Optoelectronic tweezers are a new technology that uses light induced dielectrophoresis fields to distinguish individual live cells from dead cells. We assessed the ability of optoelectronic tweezers to distinguish viable from nonviable individual nonmotile human sperm. Fresh semen specimens from 6 healthy men were suspended in an isotonic sucrose/dextrose solution and incubated with 0.4% trypan blue dye (Sigma-Aldrich®). Within 15 minutes we randomly selected 5 motile and 50 nonmotile sperm, including 25 trypan negative, followed by 25 trypan positive sperm, under 200× magnification for optoelectronic tweezers assay. We recorded the individual sperm response (attraction or repulsion) to the optoelectronic tweezer field and trypan staining status. From each subject 55 unwashed sperm were individually assayed for a total of 330. All motile sperm were attracted to optoelectronic tweezers. Of 150 trypan negative (viable) sperm 132 (88%) were attracted to the optoelectronic tweezer field with 0.88 sensitivity (95% CI 0.82-0.93) vs that of the trypan blue assay. All 150 trypan positive (nonviable) sperm were repulsed by or neutral to the optoelectronic tweezer field with 1.0 specificity (95% CI 0.98-1.00) vs that of the trypan blue assay. Type I error equaled 0 and overall assay agreement was 94%. The optoelectronic tweezer assay can distinguish viable from nonviable nonmotile viable sperm with sensitivity comparable to that of the trypan blue assay and equal specificity. Optoelectronic tweezers are a promising means of selecting sperm for intracytoplasmic sperm injection.

Analysis of the outcome of intracytoplasmic sperm injection using fresh or frozen sperm

• To compare the outcome of first-attempt intracytoplasmic sperm injection (ICSI) ICSI--embryo transfer (ET) cycles using frozen-thawed testicular sperm (FTTS), fresh testicular sperm (FTS), frozen-thawed epididymal sperm (FTES) and fresh epididymal sperm (FES) so as to determine which of these has the most successful ICSI outcome with respect to fertilization rate (FR), pregnancy rate (PR) and birth rate. • To assess the outcomes according to the underlying aetiology of azoospermia. • The records of 493 patients undergoing first-attempt ICSI between 1993 and 2008 were reviewed retrospectively. FTS was used in 112 cycles, FTTS in 43 cycles, FES in 279 cycles, and FTES in 59 cycles. • Within each group, the aetiology of the azoospermia was recorded according to history, clinical examination and histological analysis (n = 316). • The FR, clinical PR and delivery rate were calculated for each group with respect to the type of sperm retrieval used. • Analysis of the data showed no significant differences between any of the four groups in the FR, PR or delivery rate (P > 0.05). • There were no significant differences seen between fresh sperm (FTS and FES) and frozen sperm (FTTS and FTES) or between epididymal sperm (FES and FTES) and testicular sperm (FTS and FTTS) in any of the outcomes measured (P > 0.05). However, subset analysis showed a statistically higher FR and PR for FTTS over fresh sperm. • When comparing aetiologies, there was no significant difference in the FR, clinical PR and delivery rate between obstructive azoospermia (OA) and non-obstructive azoospermia (NOA) groups. However, sub-set analysis showed a higher PR and birth rate for FTTS over fresh sperm in both OA and NOA groups. • The results of the present study suggest that using frozen sperm in ICSI cycles is a reliable and favourable method with the same outcome as fresh sperm. • Testicular and epididymal sperm have similar ICSI outcomes for both fresh and frozen samples. However, results suggest a tendency for higher PRs and birth rates for frozen than for fresh testicular sperm in both OA and NOA aetiologies. • The aetiology of azoospermia does not significantly affect the outcome of first-attempt ICSI. The higher rates in the frozen groups suggest that these patients have had better quality semen when they were initially harvested and frozen.

A sperm viability test using SYBR-14/propidium iodide flow cytometry as a tool for rapid screening of primary ciliary dyskinesia patients and for choosing sperm sources for intracytoplasmic sperm injection

Spermatozoa viability tests based on dual-color flow cytometry after staining with Sybr-14/propidium iodide were performed on 44 men with complete asthenospermia for primary ciliary dyskinesia (PCD) screening, and seven were identified with PCD by electron microscopy of ultrastructural ciliary defects. Six PCD patients underwent eight intracytoplasmic sperm injection therapy cycles using ejaculated sperm or testicular sperm, obtaining a mean fertilization rate of 46.6%, with three healthy babies born and one in utero at the time of writing.

Adiponectin isoform distribution in serum and in follicular fluid of women undergoing treatment by ICSI

Adiponectin is an adipokine, present in the circulation in comparatively high concentrations and different molecular weight isoforms. For the first time, the distribution of these isoforms in serum and follicular fluid (FF) and their usefulness as biological markers for infertility investigations was studied. In vitro study. University based hospital. Fifty-four women undergoing intracytoplasmic sperm injection (ICSI). Oocytes were retrieved, fertilized in vitro using ICSI, and the resulting embryos transferred. Serum was collected immediately prior to oocyte retrieval. Adiponectin isoforms (high molecular weight (HMW), medium and low molecular weight) were determined in serum and FF. Total adiponectin and the different isoform levels were compared with leptin and ovarian steroid concentrations. Adiponectin isoforms in serum and FF. Adiponectin isoform distribution differed between serum and FF; the HMW fraction made up half of all adiponectin in the serum but only 23.3% in the FF. Total and HMW adiponectin in both serum and FF correlated negatively with the body mass index and the concentration of leptin. No correlations were observed for total adiponectin or its isoforms with estradiol, progesterone, anti-Mullerian hormone, inhibin B, or the total follicle stimulating hormone (FSH) dose administered during the ovarian stimulation phase. This study shows for the first time that adiponectin isoform distribution varies between the serum and FF compartments in gonadotropin stimulated patients. A trend towards higher HMW adiponectin serum levels in successful ICSI cycles compared to implantation failures was observed; studies with larger patient groups are required to confirm this observation.

Deficiency in mouse Y chromosome long arm gene complement is associated with sperm DNA damage

BackgroundMice with severe non-PAR Y chromosome long arm (NPYq) deficiencies are infertile in vivo and in vitro. We have previously shown that sperm from these males, although having grossly malformed heads, were able to fertilize oocytes via intracytoplasmic sperm injection (ICSI) and yield live offspring. However, in continuing ICSI trials we noted a reduced efficiency when cryopreserved sperm were used and with epididymal sperm as compared to testicular sperm. In the present study we tested if NPYq deficiency is associated with sperm DNA damage - a known cause of poor ICSI success.ResultsWe observed that epididymal sperm from mice with severe NPYq deficiency (that is, deletion of nine-tenths or the entire NPYq gene complement) are impaired in oocyte activation ability following ICSI and there is an increased incidence of oocyte arrest and paternal chromosome breaks. Comet assays revealed increased DNA damage in both epididymal and testicular sperm from these mice, with epididymal sperm more severely affected. In all mice the level of DNA damage was increased by freezing. Epididymal sperm from mice with severe NPYq deficiencies also suffered from impaired membrane integrity and abnormal chromatin condensation and suboptimal chromatin protamination. It is therefore likely that the increased DNA damage associated with NPYq deficiency is a consequence of disturbed chromatin remodeling.ConclusionsThis study provides the first evidence of DNA damage in sperm from mice with NPYq deficiencies and indicates that NPYq-encoded gene/s may play a role in processes regulating chromatin remodeling and thus in maintaining DNA integrity in sperm.

Semen analysis in 21st century medicine: the need for sperm function testing

Sperm function testing, once commonly performed for the infertile couple before employing assisted reproductive technology (ART), has fallen out of favour in many reproductive medicine centers throughout the world. Indeed, the most recent addition of the 'World Health Organisation (WHO) Laboratory Manual for the Examination and Processing of Human Semen' now groups many of these procedures into a section termed Research Procedures. In large part, this reflects the current clinical practice of bypassing the in-depth evaluation of the male partner, while assuming that if a spermatozoon can be found for intracytoplasmic sperm injection (ICSI), it must be a healthy cell capable of achieving fertilization. Nevertheless, sperm function testing can provide valuable clinical insights into defects causing male infertility. Admittedly, in some cases, functional sperm deficiencies can be overcome using an ART. In other cases, couples will be empowered by the knowledge of the cause of their infertility, and for some couples, perhaps even the likelihood of ICSI success (relative to the spermatozoa). The knowledge allows them to make truly informed reproductive decisions, including (perhaps) the decision to seek donor insemination, to adopt or to remain childless. Knowledge of the cause of their infertility may provide closure for couples and a sense of confidence regarding their choice of reproductive treatment.

The Efficacy of Recombinant Human Follicle‐Stimulating Hormone in the Treatment of Various Types of Male‐Factor Infertility at a Single University Hospital

The aim of the study was to prospectively investigate the efficacy of recombinant human follicle-stimulating hormone (rhFSH) in the treatment of various types of male-factor infertility at a single university hospital. The study included 61 infertile men receiving rhFSH because of various type of male infertility. Treatment included 100-150 IU of rhFSH 2-3 times/wk. All men were divided into 4 groups: hypogonadotropic hypogonadism (n = 21), isolated follicle-stimulating hormone (FSH) deficiency (n = 13), idiopathic oligoasthenospermia (n = 16) and maturation arrest on testicular biopsy (n = 11). Total motile sperm count (TMSC), serum FSH level, and testicular volume were compared before and after treatment in all groups. In the hypogonadotropic hypogonadism group, spermatozoa appeared in the ejaculate, with a mean TMSC of 6.67 +/- 1.57 million, in 15 of 21 patients (71.4%) who were totally azoospermic before the treatment. In the isolated FSH deficiency group, TMSC significantly increased from 6.64 +/- 3.27 to 32.4 +/- 9.09 million after the treatment (P = .003). TMSC did not significantly increase in the idiopathic oligoasthenospermia group. Two of the men with maturation arrest (18.1%) had spermatozoa in the ejaculate after the treatment. rhFSH therapy may be effectively used to improve sperm parameters in infertile men with hypogonadotropic hypogonadism and isolated FSH deficiency. In addition, rhFSH may effect some improvement by either providing sperm in ejaculate or increasing intracytoplasmic sperm injection success in infertile men with maturation arrest.

Success of intracytoplasmic sperm injection to restore fertility after male surgical sterilization

OBJECTIVE: Male surgical sterilization (MSS) is considered to be permanent but can be reversed in some cases. High failure rates of the reversal have been reported in various studies - reasons include impaired sperm transport and the presence of antibodies in sperm. Intracytoplasmic sperm injection (ICSI) has been used to overcome these difficulties for men to restore fertility after MSS. We studied outcomes of this clinical application.DESIGN: Retrospective cohort studyMATERIALS AND METHODS: Data on IVF procedures were collected by the Centers for Disease Control and Prevention using the U.S. National ART Surveillance System. We included IVF fresh non-donor cycles performed during 2004-2007, for couples with male-factor as the only infertility indicator. With adjustment for factors of female partners (such as age and reproductive history), a stratified logistic regression model by sperm collection methods was used to compare IVF outcomes between two study groups: MSS treated with ICSI (Group A), and non-MSS treated with donor sperm (Group B). Semen quality was assumed comparable between the two study groups.RESULTS: We analyzed 215 IVF cycles in Group A, and 884 in Group B. Among Group A, sperm was collected using epididymal aspiration (EA) - 55%, or testicular biopsy (TB) - 45%. All sperm was obtained through ejaculation in Group B. Favorable IVF outcomes were observed in Group A with sperm collected using EA – clinic pregnancy: 59.0 % (adjusted odds ratio (AOR): 1.43, 95% CI: 0.95-2.16) and live-birth delivery: 52.1 % (AOR: 1.48, 95% CI: 0.99-2.22), compared to 45.9% and 38.5%, respectively in Group B. Results of these two treatment outcomes were similar between Group A with sperm collected using TB and Group B.CONCLUSIONS: ICSI can successfully retore fertility for men with previoius surgical sterilization, especially if sperm was collected through epididymal aspiration, to achieve intrauterine pregnancy and live-birth rates comparable to those resulting from IVF cycles using donor sperm for male-factor infertility. OBJECTIVE: Male surgical sterilization (MSS) is considered to be permanent but can be reversed in some cases. High failure rates of the reversal have been reported in various studies - reasons include impaired sperm transport and the presence of antibodies in sperm. Intracytoplasmic sperm injection (ICSI) has been used to overcome these difficulties for men to restore fertility after MSS. We studied outcomes of this clinical application. DESIGN: Retrospective cohort study MATERIALS AND METHODS: Data on IVF procedures were collected by the Centers for Disease Control and Prevention using the U.S. National ART Surveillance System. We included IVF fresh non-donor cycles performed during 2004-2007, for couples with male-factor as the only infertility indicator. With adjustment for factors of female partners (such as age and reproductive history), a stratified logistic regression model by sperm collection methods was used to compare IVF outcomes between two study groups: MSS treated with ICSI (Group A), and non-MSS treated with donor sperm (Group B). Semen quality was assumed comparable between the two study groups. RESULTS: We analyzed 215 IVF cycles in Group A, and 884 in Group B. Among Group A, sperm was collected using epididymal aspiration (EA) - 55%, or testicular biopsy (TB) - 45%. All sperm was obtained through ejaculation in Group B. Favorable IVF outcomes were observed in Group A with sperm collected using EA – clinic pregnancy: 59.0 % (adjusted odds ratio (AOR): 1.43, 95% CI: 0.95-2.16) and live-birth delivery: 52.1 % (AOR: 1.48, 95% CI: 0.99-2.22), compared to 45.9% and 38.5%, respectively in Group B. Results of these two treatment outcomes were similar between Group A with sperm collected using TB and Group B. CONCLUSIONS: ICSI can successfully retore fertility for men with previoius surgical sterilization, especially if sperm was collected through epididymal aspiration, to achieve intrauterine pregnancy and live-birth rates comparable to those resulting from IVF cycles using donor sperm for male-factor infertility.

Sperm samples (SS) from infertile patients (IP) undergoing intracytoplasmic sperm injection (ICSI) or intrauterine insemination (IUI) show profound different expression profiles (EP)

OBJECTIVE: Basic SS analysis presents limited predictive power on pregnancy achievement by assisted reproductive techniques (ARTs). Other molecular factors as mRNA present within spermatozoa have recently been described. Our group listed genes differentially expressed (GDE) from SS from pregnant (group P) vs. those non pregnant (group NP) by microarray technology in couples undergoing homologous IUI and ICSI. Our aim is to characterize differential gene EP between SS achieving or not pregnancy in ICSI and IUI cycles. DESIGN: Nested cases and controls study, where 10 SS (5 that achieved pregnancy and 5 failing to conceive) were obtained from IP undergoing IUI with healthy female partners and ICSI cycle with oocytes from young donors. After freezing aliquots of the SS employed for both treatments we compared their respective mRNA expression profiles. Finally 4 microarrays in duplicate were performed with sperm samples from group P vs. NP from both techniques. MATERIALS AND METHODS: SS mRNA was extracted using Trizol, suspended in DEPC-treated water and frozen at -80ºC until the microarray experiments were performed. RNAs were analyzed on Agilent Bioanalyzer 2100 and those genes differentially expressed (GDE) at least twice, with statistically significant differences between P and NP in IUI and ICSI SS were listed and compared. RESULTS: Total number of genes expressed (TNG) in IUI microarray was 19938 and 19229 in ICSI. About 70 % of TNG was common in both procedures. Around 50% of GDE in group P of ICSI group were GDE in group P from IUI group too. There are more GDE (950) in IUI group compared with ICSI group (49). CONCLUSIONS: These data reveals that sperm EP is consistent and molecular features required to pregnant are different in IUI and ICSI procedures. These differences could be potentially employed to detect ICSI and IUI success markers, although it needs to be further explored in order to figure out their biological roles.

A significantly different transcriptome is found between sperm samples from infertile patients (IP) undergoing intracytoplasmic sperm injection (ICSI) achieving or not pregnancy with donated oocytes

OBJECTIVE: Basic sperm samples (SS) analysis has limited predictive power to forecast pregnancy achievement in ICSI. Our work's aim is to use microarray technology to characterize differential expression profile (EP) between SS achieving (group P) or not pregnancy (group NP) by ICSI procedure. DESIGN: Nested cases and controls study, where 10 SS (5 that achieved pregnant (group P) vs. 5 who not (group NP)) were obtained from IP undergoing ICSI cycle with oocytes from young donors. We selected 5 cases where an oocyte donor donates oocytes to two couples, and one get pregnant while the second not. After freezing aliquots of the sperm samples employed for ICSI treatment their respective mRNA EP were compared. MATERIALS AND METHODS: Sperm mRNA was extracted using Trizol protocol, suspended in DEPC-treated water and frozen at -80°C until the microarray experiments were performed. RNAs were analyzed on Agilent Bioanalyzer 2100. Genes differentially expressed (GDE) were those with a fold-change>2 and with statistically significant differences between P and NP groups (p-value <0.05). RESULTS: The total number of expressed genes detected in our microarray analysis was 19229. 16035 were commonly expressed in both groups (P and NP). Among those common transcripts, presenting increased expression, 44 GDE (i.e.: 4 cathepsins (H, B, L and Z) and 6 types of metallothioneins (1B, AH, 1X, 1A, 1F and 1G) were found in group P, whereas only 5 were found in group NP (ENST00000317633, C19orf36, COX7B2, ANKRD7 and CDKN2D). CONCLUSIONS: To our knowledge, this is the first work describing profound differences in the expression profiles between SS which achieved pregnancy vs. those unable in ICSI assisted reproduction technique using ovum donation to homogenise the female factor. These differences could be potentially employed to detect ICSI success markers, although it needs to be further explored in order to figure out their biological roles.

Removal of Acrosomal Membrane from Sperm Head Improves Development of Rat Zygotes Derived from Intracytoplasmic Sperm Injection

When intracytoplasmic sperm injection (ICSI) is applied in the rat, sperm chromatin is introduced into the oocyte together with the acrosome, which does not enter the cytoplasm of the oocyte during normal fertilization, resulting in the rat giving birth to pups. Since successful ICSI was reported in rats, but with low efficiency, it has been observed that the acrosome of the sperm head seems to have detrimental effects on the embryonic development of ICSI oocytes. To improve ICSI in rats, the effects of removal of the acrosomal membrane from rat sperm on the development of ICSI oocytes were examined. While most control (non-treated) sperm had an intact acrosomal membrane, the Triton X-100 (TX)- and lysolecithin (LL)-treated groups showed high percentages of sperm with a removed acrosomal membrane. The timing of pronuclear formation in ICSI-oocytes using TX- or LL-treated sperm was significantly accelerated compared with that of the control sperm (P<0.05). However, neither TX nor LL treatment affected amounts of PLCzeta in rat sperm. The rates of offspring derived from TX- (20.3 +/- 4.4%) and LL-treated sperm (19.0 +/- 2.8%) were also significantly higher than that of the control group (7.6 +/- 2.3%; P<0.05). Our data clearly indicate that removal of acrosomal membranes from sperm by reagents is effective for generation of offspring via ICSI in rats.

Spontaneous pregnancy after successful ICSI treatment: evaluation of risk factors in 899 families in Germany

There are only scarce data on the incidence of spontaneous pregnancy in infertility patients. Contraception after infertility treatment is another topic that has been neglected so far. Therefore, a questionnaire was sent to 1614 couples with a child conceived by intracytoplasmic sperm injection (ICSI) aged 4–6 years. A total of 899 couples responded (response rate 55.7%). A total of 10.9% of couples had used contraception. Of the couples that had actively tried to conceive, 20.0% had conceived spontaneously, resulting in a live-birth rate of 16.4%. 74.5% of these pregnancies were conceived within 2 years after delivery. A further 26.6% of couples conceived again by ICSI, with a live-birth rate of 20.9%. Maternal age was the only prognostic factor for spontaneous conception. Parents of multiples after ICSI did not have a higher chance of spontaneous conception than parents of singletons. Couples can be counselled that one out of five couples conceive spontaneously after successful ICSI. Even when assuming that none of the families that were lost to follow-up had conceived spontaneously, one out of eight couples would have conceived spontaneously. Therefore, it is important to counsel patients about the possibility of natural conception and necessity to use contraception despite their history of subfertility.

The role of sperm aneuploidy as a predictor of the success of intracytoplasmic sperm injection?

We present the first powered prospective study to assess whether sperm aneuploidy can predict the outcome of ICSI. Our null hypothesis was that aneuploidy rates (AR) are identical in men who achieve successful (Group A) and unsuccessful (Group B) ICSI outcome. A power calculation yielded a sample number of 56 to achieve 80% power to reject our hypothesis at the 5% significance level. Samples for testing were obtained on the day of embryo transfer and tests were performed on raw pre-preparation samples. Sperm AR of chromosomes 13, 18, 21, X/Y were assessed using fluorescence in-situ hybridization (FISH) techniques (mean of 1223 sperm). There was no significant difference in any patient, seminal, cycle or laboratory characteristic between groups that may have affected outcome. Total AR (2.37 versus 1.18%, P = 0.01), as well as AR of chromosomes 18, X/Y and 18 + X/Y (1.48 versus 0.67%, P = 0.005) were significantly higher in Group B compared with Group A. Regression analysis confirmed these differences to be independent of other variables and showed a 2.6-fold change in odds of achieving a pregnancy for every 1% change in total AR. Our findings confirm a potential role for aneuploidy testing in the work-up of ICSI patients as a predictor of success, as well as in future genetic counselling. If confirmed, there may also be a place for a study of preimplantation genetic screening to improve ICSI success in men found to have high AR and ICSI failure.

Sperm DNA decondensation and sperm penetration assay with gradient preparation are not predictive of pregnancy outcome in in vitro fertilization cycles with intracytoplasmic sperm injection

Recently, several sperm structure tests that detect compromised DNA integrity have been shown to have poor predictive capacity for successful Intracytoplasmic Sperm Injection (ICSI) cycles. This is believed to be the result of improved selection of the ‘prime’ sperm for use in ICSI, by use of a density gradient. Here we evaluate if two different sperm function tests, the Sperm DNA Decondensation (SDD) and the Sperm Penetration Assay (SPA), have the capacity to predict success in ICSI cycles. The SDD Test measures the fraction of cells fully decondensed after a 15 minute incubation in frog egg extract, measuring delayed decondensation while the SPA measures the sperm capacitation index (SCI), the average number of sperm penetrations per zona-free hamster oocyte.

P-460: Role of endometrial thickness on intracytoplasmic sperm injection (ICSI) outcome

Despite the widespread use of high-resolution ultrasound equipment, the clinical significance of differences in endometrial thickness and pattern has remained controversial and was not established positive predictive value. The aim of this study was to evaluate the role of endometrial thickness in ICSI success.

P-598: Morphology of extracted testicular sperm correlates with fertilization rates but not pregnancy in IVF/ICSI

Testicular sperm extraction (TESE) in conjunction with intracytoplasmic sperm injection (ICSI) results in high fertilization rates and pregnancy rates in the majority of patients who undergo these procedures. It is currently unknown whether sperm morphology on the day of TESE is an important factor in IVF/ ICSI success. We sought to investigate whether sperm morphology on the day of TESE with ICSI impacts fertilization and pregnancy rates.

Intracytoplasmic sperm injection in the bovine induces abnormal [Ca2+]i responses and oocyte activation

Fertilisation by intracytoplasmic sperm injection (ICSI), a technique that bypasses the membrane fusion of the gametes, has been widely used to produce offspring in humans and mice. Success with this technique has lent support to the hypothesis that in mammalian fertilisation, a factor from the sperm, the so-called sperm factor, is responsible for oocyte activation and that the fusion process is not involved in the generation of the hallmark [Ca2+]i signalling seen following fertilisation. However, the success of ICSI has largely eluded large domestic species, such as the bovine, porcine and equine, casting doubt on the current model of oocyte activation at fertilisation in these species. Using Ca2+ imagery and a series of treatments to manipulate the chemical structure of the sperm, we have investigated the early events of oocyte activation in response to ICSI in the bovine. Our results demonstrate, for the first time, that following ICSI, the majority of bovine oocytes are unable to mount [Ca2+]i oscillations, although, in few cases, the initiation of [Ca2+]i oscillations can occur in a manner indistinguishable from in vitro fertilisation. We also show that bull sperm possess a full complement of sperm factor. However, either the release and/or activation of the sperm factor are compromised after ICSI, leading to the delivery of a defective Ca2+ stimulus, which results in premature termination of embryo development.