Intracytoplasmic sperm injection increased fertilization and good-quality embryo formation in patients with non-male factor indications for in vitro fertilization: a prospective randomized study

Efficacy of intracytoplasmic sperm injection in women with non-male factor infertility: A systematic review and meta-analysis

INTRODUCTION

The use of intracytoplasmic sperm injection (ICSI) has dramatically increased in patients with non-male factor infertility during the last decades. However, whether ICSI provides a significant benefit over in vitro fertilization (IVF) in these patients is still controversial. In this study, we aimed to investigate the efficacy of ICSI on reproductive outcomes with non-male factor infertility and to provide updated evidence for clinical practice.

MATERIAL AND METHODS

We searched Medline, Embase, and the Cochrane Central Register of Controlled Trials from inception to March 2023. Randomized controlled trials (RCTs) comparing the efficacy between ICSI and IVF in patients with non-male factor infertility were included. The main outcomes were the live birth rate (LBR), fertilization rate (FR), and total fertilization failure (TFF). The pooled estimates were calculated using the random-effects models as relative risk (RR) with 95% confidence intervals (CIs). This systematic review and meta-analysis was registered in PROSPERO (CRD42023427004).

RESULTS

We included 18 RCTs with 3249 cycles and 30 994 oocytes. The results demonstrated that ICSI reduced the risk of TFF (RR = 0.26, 95% CI: 0.13-0.50, I2  = 58%) and increased FR per oocyte inseminated/injected (RR = 1.14, 95% CI: 1.08-1.20, I2  = 69%), but it did not improve LBR (RR = 1.11, 95% CI: 0.94-1.30, I2  = 0%) or other outcomes compared with IVF. However, the difference in fertilization failure reduction between ICSI and IVF may be explained by different randomization methods (randomization based on patients vs. sibling oocytes). When considering only studies with randomization based on patients, we found no evidence of the difference between the groups (RR = 0.72, 95% CI: 0.48-1.06, I2  = 0%). Furthermore, no differences were observed in subgroup analyses based on other factors, including female age, study period, and controlled ovarian stimulation protocols.

CONCLUSIONS

Our findings suggest that ICSI leads to no difference in reproductive outcomes compared to IVF in patients with non-male factor infertility. Considering the cost and safety of ICSI, we have no evidence to support the routine use of ICSI in these populations. High-quality RCTs with large sample sizes will be needed to confirm our results and explore clinical and neonatal outcomes.

Intracytoplasmic sperm injection does not improve the outcome of IVF treatments in patients with advanced maternal age or low oocyte number: A randomized controlled trial

INTRODUCTION

Intracytoplasmic sperm injection (ICSI) was introduced to achieve fertilization in cases of severe male factor infertility. However, ICSI is often used in cases of non-male factor infertility, such as advanced maternal age or low oocyte number, but the clinical benefit of the method in these indications has not been proven.

MATERIAL AND METHODS

A prospective randomized study was conducted in a university clinic between 2018 and 2020. Patients with ≥40 years of age and/or ≤4 oocytes with non-sever male factor infertility were randomized into conventional IVF or ICSI groups. Fertilization rate, embryo quality, implantation, clinical pregnancy and live birth rates were compared.

RESULTS

A total of 336 IVF cycles (169 conventional IVF and 167 ICSI) were involved in the study. The fertilization rate was higher in the conventional IVF group compared to the ICSI group (IVF: 61.7%, ICSI: 53.4%, P=0.001). Embryo development and morphology did not show considerable difference between groups. Implantation, clinical pregnancy and live birth rate were 13.1%, 24.3% and 11.4% in the conventional IVF and 10.4%, 19.0%, 12.0% in the ICSI group. The differences were not significant. Subgroup analysis showed a significantly better clinical outcome following conventional IVF when advanced maternal age was accompanied by low oocyte number (Implantation: 11.7% vs 2.6%, P=0.027; Clinical pregnancy: 18.5% vs 4%, P=0.020).

DISCUSSION

A significantly higher fertilization rate, a tendency for higher clinical pregnancy rate was found in conventional IVF treatments compared to ICSI. When advanced maternal age was associated with low oocyte number, ICSI resulted in a substantially lower chance of fertilization and clinical pregnancy. These data suggest that ICSI offers no advantage over conventional IVF in terms of fertilization, embryo quality, implantation and pregnancy rates for couples with advanced maternal age or with low oocyte number.

Duration of infertility and assisted reproductive outcomes in non-male factor infertility: can use of ICSI turn the tide?

Background

Intracytoplasmic sperm injection (ICSI) is increasingly used among in vitro fertilization (IVF) cycles without male factor infertility. For couples with prolonged infertility duration, the preferred insemination method may vary across laboratories and clinics. We analyzed whether ICSI is effective for non-male factor infertility with long infertility duration.

Methods

Seventeen thousand four hundred seventy-seven IVF/ICSI cycles from women with non-male factor infertility were included, of these 4177 women with infertility duration ≥ 5 years were in the final analysis. Primary outcome was the live birth rate after first embryo transfer. Secondary outcomes were rates of clinical pregnancy and fertilization.

Results

A nonlinear relationship was observed between infertility duration and IVF fertilization rate, which decreased with infertility years up to the turning point (4.8 years). 4177 women with infertility ≥ 5 years were categorized by IVF (n = 3806) or ICSI (n = 371). Live birth rate after first embryo transfer was 43.02% in ICSI and 47.85% in IVF group (adjusted odds ratio (aOR), 0.91; 95% confidence interval (CI), 0.72–1.15). Fertilization rate per metaphaseII (aOR, 1.10; 95% CI, 0.86–1.40) and clinical pregnancy rate (aOR, 0.89; 95% CI, 0.71–1.13) were similar between the two groups. Sensitive analyses (women ≥ 35 years) did not show a benefit of ICSI over IVF.

Conclusions

Women with infertility exceeding 4.8 years had decreased incidence of IVF fertilization. The use of ICSI showed no significant improvement in fertilization and live birth rates for non-male factor couples with ≥ 5 years of infertility.

Impact of intracytoplasmic sperm injection in women with non-male factor infertility: A systematic review and meta-analysis

OBJECTIVE

The purpose of this study is to determine whether intracytoplasmic sperm injection (ICSI) is beneficial in patients with non-male factor infertility.

METHODS

This systematic review and meta-analysis included articles from inception to May 2022. Published studies of non-male factor infertile women undergoing ICSI or in vitro fertilization (IVF) included in PubMed, Embase, web of science, Wanfang Database, and CNKI were searched by computer, without language restrictions. A random-effect model was applied to calculate the risk ratios (RRs) and their 95% confidence intervals (CIs). Letters, case reports, and review articles including meta-analyses and expert opinions were excluded. The primary endpoints were laboratory outcomes and pregnancy outcomes. The Secondary endpoints were neonatal outcomes.

RESULTS

Six randomized controlled studies and 20 retrospective cohort studies met the inclusion criteria. In meta-analytic forest plots, compared with IVF, those who received ICSI treatment were not different in fertilization rate (RR = 0.99, 95% CI [0.90-1.09], P = 0.88), total fertilization failure rate (RR = 1.30, 95% CI [1.17-1.45], P < 0.00001), and good quality embryo rate (RR = 0.94, 95% CI [ 0.86-1.02], P = 0.15), clinical pregnancy rate (RR = 0.84, 95% CI [0.70-1.01], P = 0.06), live birth rate (RR = 0.89, 95% CI [0.77-1.03], P = 0.13), miscarriage rate (RR = 1.06, 95% CI [0.78-1.43], P = 0.71), preterm neonatal delivery rate (RR = 0.92, 95% CI [0.67-1.26], P = 0.61), and low neonatal weight rate (RR = 1.13, 95% CI [0.80-1.61], P = 0.48). However, the implantation rate of IVF was better than ICSI (RR = 0.77, 95% CI [0.64-0.93], P = 0.005). In the subgroup analysis of the live birth rate of fresh embryo transfer, IVF performed in those ≥35 years had a higher live birth rate (RR = 0.82, 95% CI [0.78-0.83], P < 0.001).

CONCLUSION

The findings of this study indicate that ICSI is not superior to IVF in the treatment of infertility related to non-male factors. In order to confirm this result, more high-quality clinical studies are needed.

Should Intra Cytoplasmic Sperm Injection (ICSI) be the primary insemination method in women undergoing IVF cycles with donor sperm?

PURPOSE

To compare efficacy of Intra Cytoplasmic Sperm Injection (ICSI) with conventional in vitro fertilization (IVF) on treatment outcome in women undergoing in vitro fertilization with donor sperm.

METHODS

We examined retrospectively the outcome data from 203 patients undergoing fresh cycles of conventional IVF (cIVF) or ICSI and an additional 77 frozen-thawed embryo transfer (FET) cycles during 2003-2014, all using donor sperm. Fertilization, cleavage, pregnancy and live birth rates and number of high-quality embryos were compared between cIVF and ICSI.

RESULTS

Altogether 185 women underwent 479 transfer cycles of fresh embryos (237 cIVF vs. 224 ICSI and 18 "rescue ICSI" cycles). In addition, 77 FET cycles were compared (24 cIVF vs. 53 ICSI cycles). No differences were found between cIVF and ICSI in fertilization, cleavage, pregnancy and live birth rates (92.6% vs 92.2%, 73.4% vs 72.4%, 25.3% vs 27.2% and 13.1% vs 14.7%, respectively). Pregnancy and life birth rates remained similar even when FET cycles were included (25.8% vs 26.2% and 13.1% vs 13.7%, respectively). The use of ICSI was associated with lower rates of high-quality embryos (52.7% vs. 63.3%, P < 0.0001). A multivariate logistic regression analysis found that patients' age, number of transferred embryos and smoking were independently associated with the chance to conceive. Patient age correlated inversely with fertilization rate (r = - 0.13, P < 0.006).Non-smokers were more likely to become pregnant (OR = 2.23, P < 0.012).

CONCLUSIONS

Our results show that ICSI does not bypass the age-related decrease in oocyte quality in patients using donor sperm for IVF. Use of ICSI was associated with lower rates of high-quality embryos. The findings imply that ICSI should not be the primary method of insemination in patients undergoing IVF with donor sperm.

Marginal differences in preimplantation morphokinetics between conventional IVF and ICSI in patients with preimplantation genetic testing for aneuploidy (PGT-A): A sibling oocyte study

Objective

This study aimed to analyze the morphokinetic behaviour between conventional IVF and ICSI, in cycles with preimplantation genetic testing for aneuploidies (PGT-A).

Materials

A randomized controlled trial (NCT03708991) was conducted in a private fertility center. Thirty couples with non-male factor infertility were recruited between November 2018 and April 2019. A total of 568 sibling cumulus oocyte complexes were randomly inseminated with conventional IVF and ICSI and cultured in an Embryoscope time-lapse system. The morphokinetic behaviour of IVF/ICSI sibling oocytes was analysed as primary endpoint. As secondary endpoints, morphokinetic parameters that predict blastocysts that will be biopsied, the day of biopsy, gender and euploid outcome was assessed.

Results

When comparing IVF to ICSI, only the time to reach the 2-cell stage (t2) was significantly delayed for IVF embryos: OR: 1.282 [1.020–1.612], p = 0.033. After standardizing for tPNf (ct parameters), only Blast(tStartBlastulation-t2) remained significant: OR: 0.803 [0.648–0.994], p = 0.044. For the analysis of zygotes that will be biopsied on day 5/6 versus zygotes without biopsy, only early morphokinetic parameters were considered. All parameters were different in the multivariate model: ct2: OR: 0.840 [0.709–0.996], p = 0.045; ct6: OR: 0.943 [0.890–0.998], p = 0.043; cc2(t3-t2): OR: 1.148 [1.044–1.263], p = 0.004; cc3(t5-t3): OR: 1.177 [1.107–1.251], p<0.0001. When comparing the development between blastocysts biopsied on day 5 versus day 6, only three morphokinetic parameters were significant: cc2(t3-t2): OR: 1.394 [1.010–1.926], p = 0.044; ctBlastocyst: OR: 0.613 [0.489–0.768], p<0.0001 and ctExpandedBlastocyst: OR: 0.913 [0.868–0.960], p = 0.0004. Multivariate analysis of gender and ploidy did not reveal differences in morphokinetic behaviour.

Conclusion

Minor morphokinetic differences are observed between IVF and ICSI. Early in the development, distinct cleavage patterns are observed between embryos that will be biopsied or not.

The Impact of Intracytoplasmic Sperm Injection in Non-Male Factor Infertility-A Critical Review

Intracytoplasmic sperm injection (ICSI) was originally designed to overcome barriers due to male factor infertility. However, a surveillance study found that ICSI use in non-male factor infertility increased from 15.4% to 66.9% between 1996 and 2012. Numerous studies have investigated fertilization rate, total fertilization failure, and live birth rate per cycle (LBR), comparing the use of ICSI versus conventional in vitro fertilization (IVF) for non-male factor infertility. The overwhelming conclusion shows no increase in fertilization rate or LBR per cycle with the use of ICSI for non-male factor infertility. The overuse of ICSI is likely related to the desire to avoid a higher rate of total fertilization failure in IVF. However, data supporting the benefit of using ICSI for non-male factor infertility is lacking, and 33 couples would need to be treated with ICSI unnecessarily to avoid one case of total fertilization failure. Such practice increases the cost to the patient, increases the burden on embryologist’s time, and is a misapplication of resources. Additionally, there remains conflicting data regarding the safety of offspring conceived by ICSI and potential damage to the oocyte. Thus, the use of ICSI should be limited to those with male factor infertility or a history of total fertilization factor infertility due to uncertainties of potential adverse impact and lack of proven benefit in non-male factor infertility.

Intracytoplasmic sperm injection is not superior to conventional IVF in couples with non-male factor infertility and preimplantation genetic testing for aneuploidies (PGT-A)

STUDY QUESTION

Does the insemination method impact the euploidy outcome in couples with non-male factor infertility?

SUMMARY ANSWER

Conventional IVF can be applied in cycles with preimplantation genetic testing for aneuploidies (PGT-A), as both IVF and ICSI generate equal numbers of euploid blastocysts.

WHAT IS KNOWN ALREADY

Ever since its introduction, the popularity of ICSI has increased tremendously, even in couples with non-male factor infertility. The use of conventional IVF is a contraindication for couples undergoing PGT to ensure monospermic fertilisation and to eliminate potential paternal contamination from extraneous sperm attached to the zona pellucida. Despite this, it has recently been shown that sperm DNA fails to amplify under the conditions used for trophectoderm biopsy samples.

STUDY DESIGN, SIZE, DURATION

This single-centre prospective pilot study included 30 couples between November 2018 and April 2019.

PARTICIPANTS/MATERIALS, SETTING, METHOD

Arab couples, with a female age between 18-40 years, body mass index ≤30 kg/m2, at least 10 cumulus oocyte complexes (COCs) following oocyte retrieval (OR) and normal semen concentration and motility (WHO) in the fresh ejaculate on the day of OR, were eligible for the study. Half of the sibling oocytes were assigned to conventional IVF, and the other half were assigned to ICSI. All embryos were cultured in a time-lapse imaging system in Global Total LP media. Blastocysts were subjected to trophectoderm biopsy on Day 5, 6 or 7 and next-generation sequencing (NGS) to determine blastocyst ploidy status. The primary objective was to determine the euploid rate in blastocysts from sibling oocytes.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 568 COCs were randomly allocated between IVF (n = 283; 9.4 ± 4.0) and ICSI (n = 285; 9.5 ± 4.1). While the incidence of normal fertilisation per cycle (6.1 ± 3.8 (64.0%) vs 6.3 ± 3.5 (65.4%); P = 0.609) was distributed equally between IVF and ICSI, the degeneration rate (0.1 ± 0.3 vs 0.7 ± 0.8; P = 0.0003) was significantly higher after ICSI and the incidence of abnormal fertilisation (≥3 pronuclei) was significantly higher after IVF (0.9 ± 1.2 vs 0.2 ± 0.4; P = 0.005). For all fertilised oocytes, there were no differences in the number of good-quality embryos on Day 3 (74% vs 78%; P = 0.467), nor in the blastulation rate on Day 5 (80.4% vs 70.8%; P = 0.076). The total number of blastocysts biopsied per cycle on Days 5, 6 and 7 was not significantly different between IVF or ICSI (4.0 ± 2.8 vs 3.9 ± 2.5; P = 0.774). With euploid rates of 49.8 and 44.1% (P = 0.755; OR: 1.05664 [0.75188-1.48494), respectively, there was no significant difference identified between IVF and ICSI (2.0 ± 1.8 vs 1.9 ± 1.7; P = 0.808) and all couples had at least one euploid blastocyst available for transfer. When considering only euploid blastocysts, the male/female ratio was 61/39 in IVF and 43/57 in ICSI (P = 0.063).

LIMITATIONS, REASON FOR CAUTION

This is a pilot study with a limited patient population of 30 couples (and 568 COCs) with a normal ovarian response. The results of our study should not be extrapolated to other patient populations.

WIDER IMPLICATIONS OF THE FINDINGS

It is safe to apply conventional IVF in couples with non-male factor infertility undergoing PGT-A.

STUDY FUNDING/COMPETING INTEREST(S)

No funding was obtained. There are no competing interests.

TRIAL REGISTRATION NUMBER

NCT03708991.

ICSI Does Not Improve Live Birth Rates but Yields Higher Cancellation Rates Than Conventional IVF in Unexplained Infertility

Objectives: Unexplained infertility has been one of the indications for utilization of intracytoplasmic sperm injection (ICSI). However, whether ICSI should be preferred to IVF for patients with unexplained infertility remains an open question. This study aims to determine if ICSI improves the clinical outcomes over conventional in vitro fertilization (IVF) in couples with unexplained infertility.

Methods: This was a retrospective cohort study of 549 IVF and 241 ICSI cycles for patients with unexplained infertility at a fertility center of a university hospital from January 2016 and December 2018. The live birth rate and clinical pregnancy rate were compared between the two groups. Other outcome measures included the implantation rate, miscarriage rate, and fertilization rate.

Results: The live birth rate was 35.2% (172/488) in the IVF group and 33.3% (65/195) in ICSI group, P = 0.635. The two groups also had similar clinical pregnancy rates, implantation rates, and miscarriage rates. The fertilization rate of IVF group was significantly higher than that of ICSI group (53.8 vs. 45.7%, P = 0.000, respectively). Sixty-one and 46 patients did not transfer fresh embryos in IVF and ICSI cycles, respectively. Patients with IVF cycles had lower cancellation rates than those with ICSI (11.1 vs. 19.1%, P = 0.003, respectively).

Conclusion: ICSI does not improve live birth rates but yields higher cancellation rates than conventional IVF in the treatment of unexplained infertility.

Comparison of in vitro fertilisation/intracytoplasmic sperm injection on live birth rates in couples with non-male factor infertility and advanced maternal age

PURPOSE

To determine if the use of ICSI in women of advanced maternal age with non-male factor infertility increases chances of live birth.

METHODS

Retrospective data analysis of 10 years of cycle data from a single Australian IVF clinic (Repromed). First cycle patients only of an advanced maternal age (≥ 35 years) with non-male factor infertility utilising standard IVF or ICSI insemination and having at least three oocytes collected at egg pick up were assessed for live birth following transfer of single genetically unscreened blastocyst (N = 577). Subanalysis of clinical pregnancy, miscarriage, fertilisation, embryo utilisation rate and having a blastocyst for transfer were considered. Unadjusted, covariate adjusted and propensity score weighted analysis were performed.

RESULTS

The use of standard IVF insemination in women ≥ 35 years with non-male factor infertility increased the chance of a live birth compared with ICSI insemination (unadjusted OR = 2.72, 95% CI [1.78, 4.17]; adjusted OR = 2.64, 95% CI [1.64, 4.27] and weighted OR = 2.26, 95% CI [1.72, 2.98] 31% vs 14%). All other outcomes (fertilisation rate, embryo utilisation, blastocyst for embryo transfer and miscarriage rate) were unaffected.

CONCLUSION

In couples with advanced maternal age and non-male factor infertility, standard IVF insemination appears to increase the chance of a live birth compared with ICSI. As such, the results of this study support the use of routine IVF as the preferred insemination technique for older women in non-male factor infertility. However, future randomised controlled trials are still required to assess this policy.

The effect of ICSI in infertility couples with non-male factor: a systematic review and meta-analysis

PURPOSE

We performed a systematic review and meta-analysis of available literature to investigate the efficacy of the intracytoplasmic sperm injection (ICSI) in couples with non-male factor with respect to the clinical outcomes.

METHODS

The literature search was based on EMBASE, PubMed, and the Cochrane Library. All studies published after 1992 until February 2020 and written in English addressing patients in the presence of normal semen parameters subjected to ICSI and in vitro fertilization (IVF) were eligible. Reference lists of retrieved articles were hand-searched for additional studies. The primary outcomes were fertilization rate, clinical pregnancy rate, and implantation rate; the secondary outcomes were good-quality embryo rate, miscarriage rate, and live birth rate.

RESULTS

Four RCTs and twenty-two cohort studies fulfilling the inclusion criteria were included. Collectively, a meta-analysis of the outcomes in RCTs showed that compared to IVF, ICSI has no obvious advantage in fertilization rate (RR = 1.16, 95% CI: 0.83-1.62), clinical pregnancy rate (RR = 1.04, 95% CI: 0.66-1.64), implantation rate (RR = 1.12, 95% CI: 0.67-1.86), and live birth rate (RR = 1.17, 95% CI: 0.43-3.15). Pooled results of cohort studies demonstrated a statistically significant higher fertilization rate (RR = 1.16, 95% CI: 1.03-1.31) and miscarriage rate (RR = 1.04, 95% CI: 1.01-1.06) in the ICSI group; furthermore, higher clinical pregnancy rate (RR = 0.85, 95% CI: 0.77-0.94), implantation rate (RR = 0.78, 95% CI: 0.65-0.95), and live birth rate (RR = 0.86, 95% CI: 0.79-0.94) was founded in the IVF group; no statistically significant difference was observed in good-quality embryo rate (RR = 0.98, 95% CI: 0.93-1.04).

CONCLUSION

ICSI has no obvious advantage in patients with normal semen parameters. Enough information is still not available to prove the efficacy of ICSI in couples with non-male factor infertility comparing to IVF.

ALWAYS ICSI? A SWOT analysis

PURPOSE

Intracytroplasmatic sperm injection (ICSI) is a common procedure used to improve reproductive results, even among couples without male factor infertility. However, the evidence available is still uncertain on the possible advantages and deficiencies that this procedure may have in patients with no formal indication for ICSI.

METHODS

A SWOT (strengths, weaknesses, opportunities, threats) analysis examines the possible advantages and deficiencies of performing ICSI in these patients with no formal indication.

RESULTS

The evidence suggests that ICSI is not justified for non-male factor infertile couples requiring in vitro conception. One of the major strengths associated to the procedure is the virtual elimination of cases further complicated by total fertilization failure and a combination between IVF and ICSI on sibling oocytes has been advised in the literature. Greater technical difficulties, higher costs and performing an unnecessary invasive technique in some cases represent some of the weaknesses of the procedure, and questions regarding safety issues should not be ruled out.

CONCLUSION

Despite the widespread use of ICSI in patients without a formal diagnosis of male factor infertility, evidence demonstrating its effectiveness in this population is still lacking. Additional large and well-designed randomized controlled trials are needed to clarify definitive indications for ICSI in non-male factor infertility.

Is intracytoplasmic sperm (ICSI) better than traditional in vitro fertilization (IVF): confirmation of higher blastocyst rates per oocyte using a split insemination design

PURPOSE

To explore the effects of traditional vs. intracytoplasmic sperm injection (ICSI) insemination method on the outcome of high-quality blastocyst development in a split sibling oocyte cohort.

METHODS

In this retrospective cohort study, we analyzed 62 ICSI/IVF split cycles. Sibling oocytes were randomly assigned to ICSI or IVF insemination. Two hundred thirty-four ICSI-only cycles and 152 IVF-only cycles were also analyzed for comparison. Blastocysts were graded by Gardner's embryo grading and were considered a high-quality blastocyst if 3BB or better (Gardner 1999).

RESULTS

In the ICSI/IVF split group, (1) ICSI oocytes had a higher fertilization rate per oocyte allocated (73% vs 62%, p < 0.001), (2) more high-quality day 2 embryos (69% vs 55%, p < 0.005), (3) ICSI oocytes had a lower blastulation rate per 2PN (46% vs 54%, p < 0.05), but a higher blastulation rate when calculated per oocyte allocated (40% vs 32%, p < 0.05). The ICSI-only group had a lower fertilization rate (65% vs 70%, p < 0.001) but more high-quality day 2 embryos in comparison to the IVF-only group (68% vs 64%, p < .05). The total high-quality blastulation rate was higher for the IVF-only group per 2PN (49% vs 43%, p < 0.05) and per oocyte retrieved (34% vs 28%, p < 0.05).

CONCLUSIONS

This distinctive IVF/ICSI sibling oocyte split design demonstrated a higher-quality blastulation rate in the IVF group compared to the ICSI group when calculated per 2PN, but not per oocyte allocated to each insemination procedure.

Can we predict oocyte maturation prior to denudation for intracytoplasmic sperm injection?

Intracytoplasmic sperm injection (ICSI) was introduced in 1992 as a method to treat couples with severe male infertility. However, in the last two decades, the use of ICSI has increased substantially even among patients without male factor infertility. In ICSI the oocytes are scrutinized for maturity upon insemination and the immature oocytes are discarded. The aim of the present study was to assess the ability of an experienced embryologist to identify the maturity of the oocytes prior to their denudation.In the present prospective observational study, four experienced embryologists examined the oocytes prior to their denudation and decided whether the oocytes were mature or immature. Later, the oocytes were denudated and the embryologist again examined the oocytes to confirm their prior assumptions.483 oocytes were examined by four embryologists. Three hundred and fifty one of the oocytes were mature (72.7%) and 132 were immature (27.3%). The embryologists were able to correctly identify oocytes maturation status in 85.3% of cases. The embryologists were able to correctly identify 90% of the mature oocytes and 72.7% of the immature oocytes. When they assumed that the oocytes were mature they were correct in 89.% of the cases, while only 74.6% of their prediction that the oocytes were immature were true. To conclude, the embryologists are able to identify the oocytes maturation status before denudation at the majority of the cases. Whenever the oocytes are suspected to be immature, further consideration should be made whether to proceed to ICSI or not.

Higher clinical pregnancy rate with in-vitro fertilization versus intracytoplasmic sperm injection in treatment of non-male factor infertility: Systematic review and meta-analysis

OBJECTIVE

To evaluate the evidence about in-vitro fertilization (IVF) versus intracytoplasmic sperm injection (ICSI) for the treatment of non-male factor infertility.

DATA SOURCES

Electronic databases searched using the following MeSH terms (Sperm Injection, Intracytoplasmic) AND (in Vitro Fertilisation) AND (Infertility).

METHODS OF STUDY SELECTION

All RCTs included infertile patients due to non-male factors underwent IVF or ICSI were considered for this meta-analysis. One-thousand twenty-two studies were identified of which 20 studies deemed eligible for this review.

DATA EXTRACTION

Three independent authors extracted the relevant data from included studies. The study outcomes were pooled in the form of relative risk (RR) and 95 % confidence interval (CI) using Mantel-Hansel method. The main outcome measures are the fertilization rate, the implantation rate, the clinical pregnancy rate (CPR), the total fertilization failure and the live birth rate.

RESULTS

Regarding the fertilization rate, the pooled estimate did not favour either IVF or ICSI group (RR = 0.94; 95 %CI [0.82, 1.07]; p = 0.34). However, IVF significantly increased the CPR than ICSI (RR = 1.28, 95 %CI [1.11, 1.49]; p = 0.001). The overall effect estimate did not favor either of two groups regarding the implantation rate (RR = 1.25, 95 % CI [0.92, 1.68], p = 0.15). Similarly, no difference between both groups regarding the live birth rate (RR = 1.08, 95 % CI [0.79, 1.49]; p = 0.62).

CONCLUSIONS

No difference between ICSI and IVF regarding fertilization rate per oocytes, implantation rate and live birth rate in the treatment of non-male factor infertility, while IVF has significantly higher clinical pregnancy rate and higher risk of total fertilization failure.

Conventional IVF improves blastocyst rate and quality compared to ICSI when used in patients with mild or moderate teratozoospermia

The ICSI procedure was invented to treat severe male infertility but is often used even if the sperm quality parameters are normal. This practice has recently been called into question, but there is still no clear answer especially in terms of sperm morphology, regarding when it is necessary to perform ICSI and when conventional IVF is indeed more beneficial. In borderline cases it seems logical to fertilize oocytes using ICSI and conventional IVF at the same time. Since we also use this approach we performed a retrospective analysis of such cycles to elucidate, which procedure results in a better clinical outcome in terms of fertilization rate, the quality of day 3 and day 5 embryos, and the pregnancy rate. The data from fifty-one couples who were treated with ART and whose male factor of infertility was defined as teratozoospermia were included. The fertilization rates were similar between ICSI and conventional IVF groups (per COCs: 54.5% vs. 58.2%, P = 0.322; per MII oocytes: 63.9% vs. 67.2%; P = 0.399), but more oocytes degenerated after ICSI (11.7% vs. 4.3%; P = 0.0003). The quality of cleaved embryos was similar between the groups, but more embryos reached the blastocyst stage after conventional IVF (43.7% vs. 55.0%; P = 0.032) and furthermore, more of them were of good quality (19.8% vs. 29.2%; P = 0.037). The pregnancy rate did not significantly differ between the groups (21.4% vs. 45.5%; P = 0.175), although there was a trend in favor of conventional IVF. This retrospective analysis suggests that when sperm morphology is not severely impaired and sperm concentration and motility are normal, it is better to use conventional IVF to fertilize oocytes and not ICSI. The main advantage of conventional IVF is reflected in improved blastocyst rate and quality.Abbreviations: ICSI: intracytoplasmic sperm injection; IVF: in vitro fertilization; COC: cumulus-oocyte complex; COH: controlled ovarian hyperstimulation.

Use of intracytoplasmic sperm injection (ICSI) in normospermic men may result in lower clinical pregnancy and live birth rates

BACKGROUND

While intracytoplasmic sperm injection (ICSI) was developed for overcoming male infertility, it is increasingly being used for non-male factor indications, without consensus regarding the safety and efficacy of this approach.

AIMS

To determine whether ICSI offers any benefit compared to standard in vitro fertilisation (IVF), in the setting of normal semen parameters.

MATERIALS AND METHODS

Retrospective analysis of reproductive outcomes in 3363 stimulated cycles (IVF = 1661; ICSI = 1702), in patients treated between 2009-2015, was performed. Selected couples had no male factor infertility. Couples with abnormal semen parameters (based on WHO 2010 guidelines), presence of anti-sperm antibodies and low oocyte yield of ≤4 oocytes, were excluded. The outcomes analysed included: (1) fertilisation rate (FR); (2) clinical pregnancy rate (CPR); and (3) live birth rate (LBR), by method of fertilisation used (IVF vs ICSI) and controlling for significant confounders.

RESULTS

FR, CPR and LBR were significantly higher in the IVF group compared with ICSI (67.1% vs 62.3%, 23.06% vs 16.8%, 17.22% vs 13.2%, respectively). Pregnancy rate with ICSI was approximately 30% lower than with IVF, even when controlling for significant factors such as day of embryo transfer and number of embryos transferred. This translates to one less pregnancy in every 15 cycles where ICSI was used without clear indication.

CONCLUSIONS

Our data suggest that ICSI may be detrimental to clinical outcomes and contributes to the wider understanding of use of ICSI in normospermic men.

Should ICSI be implemented during IVF to all advanced-age patients with non-male factor subfertility?

BACKGROUD

In order to maximize In vitro fertilization (IVF) success rates in advanced- age patients, it has been suggested to favor the use of intracytoplasmic sperm injection (ICSI) over conventional insemination (CI), with the notion that ICSI would serve as a tool to overcome interference in sperm oocyte interaction and sperm oocyte penetration issues that can be related to maternal age and are not due to sperm abnormalities. We therefore aim to evaluate the role of ICSI in the treatment of non-male factor infertile patients aged ≥35 in terms of fertilization and top-quality embryo rates.

METHODS

In this retrospective cohort study, data were collected and analyzed for all patients with non-male factor infertility, aged ≥35 treated, undergoing their first IVF cycle attempt with 6 or more oocytes yield, in whom a 50% ICSI-CI division was performed.

RESULTS

Five hundreds and four oocytes were collected from 52 eligible patients. Overall, 245 oocytes underwent ICSI and 259 oocytes underwent CI. The fertilization rate was 71.0% following ICSI, compared to 50.1% in the CI treated oocytes (P < 0.001). The top quality embryo rate was 62.8% following ICSI compared to 45.5% following CI (P < 0.001). Subdividing the study population to two age groups revealed that the above differences remained significant in patients aged 35-39 yrs., whereas in those aged 40-45 yrs., the differences were non-significant but still inclined in favor of ICSI.

CONCLUSIONS

This study favors the use of ICSI in the older IVF population in order to increase both the fertilization rate and the number of top quality embryos that result per IVF cycle. Further studies are needed to establish our observations and use ICSI as the preferred approach to overcome egg sperm abnormal interactions related to advanced maternal age.

An adapted carrier for the cryopreservation of human testicular spermatozoa

RESEARCH QUESTION

Does the adapted carrier Cryoplus improve the quality of cryopreserved spermatozoa compared with the use of conventional containers, and what is the effect of the adapted carrier on clinical outcomes?

DESIGN

Semen samples from 27 cases of oligozoospermia were used to investigate whether the adapted carrier improved cryopreserved sperm quality compared with the use of 0.25-ml straws and 2-ml cryogenic vials. Thirty testicular sperm samples were used to study the quality of testicular spermatozoa cryopreserved in the adapted carrier. The retrospective study included a further 104 men with azoospermia to investigate the clinical outcomes of testicular spermatozoa cryopreserved with the adapted carriers. Men with mostly obstructive azoospermia were included in this study.

RESULTS

The adapted carrier improved cryopreserved spermatozoa motility of semen samples compared with 2-ml cryogenic vials but not compared with 0.25-ml straws. No differences were found in cryopreserved sperm DNA fragmentation among the three carriers. Fertilization and good-quality embryo rates were similar in ICSI cycles using fresh or cryopreserved testicular spermatozoa. Additionally, no difference was evident between frozen-thawed embryo transfer cycles using fresh or cryopreserved testicular spermatozoa in clinical pregnancy, implantation, miscarriage, live birth rates or birth weight.

CONCLUSIONS

The adapted carrier improved the cryopreserved sperm motility compared with the effects of 2-ml cryogenic vials. The outcomes of intracytoplasmic sperm injection and frozen-thawed embryo transfer outcomes indicate that testicular spermatozoa cryopreserved using the adapted carrier is not inferior to fresh testicular spermatozoa. The use of the adapted carrier for cryopreserving human testicular spermatozoa especially from obstructive azoospermia is simple and effective.

An ICSI rate of 90% minimizes complete failed fertilization and provides satisfactory implantation rates without elevating fetal abnormalities

IVF cycles utilizing the ICSI technique for fertilization have been rising over the 25 years since its introduction, with indications now extending beyond male factor infertility. We have performed ICSI for 87% of cases compared with the ANZARD average of 67%. This retrospective study reports on the outcomes of 1547 autologous ART treatments undertaken over a recent 3-year period. Based on various indications, cases were managed within 3 groupings - IVF Only, ICSI Only or IVF-ICSI Split insemination where oocytes were randomly allocated. Overall 567 pregnancies arose from mostly single embryo transfer procedures up to December 2016, with 402 live births, comprising 415 infants and a low fetal abnormality rate (1.9%) was recorded. When the data was adjusted for confounders such as maternal age, measures of ovarian reserve and sperm quality, it appeared that IVF-generated and ICSI-generated embryos had a similar chance of both pregnancy and live birth. In the IVF-ICSI Split model, significantly more ICSI-generated embryos were utilised (2.5 vs 1.8; p < 0.003) with productivity rates of 67.8% for pregnancy and 43.4% for livebirths per OPU for this group. We conclude that ART clinics should apply the insemination method which will maximize embryo numbers and the first treatment for unexplained infertility should be undertaken within the IVF-ICSI Split model. Whilst ICSI-generated pregnancies are reported to have a higher rate of fetal abnormalities, our data is consistent with the view that the finding is not due to the ICSI technique per se.

Comparison of clinical outcomes between in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) in IVF-ICSI split insemination cycles

OBJECTIVE

This study aimed to compare the clinical outcomes between in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) in sibling oocytes. Additionally, we evaluated whether the implementation of split insemination contributed to an increase in the number of ICSI procedures.

METHODS

A total of 571 cycles in 555 couples undergoing split insemination cycles were included in this study. Among them, 512 cycles (89.7%) were a couple's first IVF cycle. The patients were under 40 years of age and at least 10 oocytes were retrieved in all cycles. Sibling oocytes were randomly allocated to IVF or ICSI.

RESULTS

Total fertilization failure was significantly more common in IVF cycles than in ICSI cycles (4.0% vs. 1.4%, p<0.05), but the low fertilization rate among retrieved oocytes (as defined by fertilization rates greater than 0% but <30%) was significantly higher in ICSI cycles than in IVF cycles (17.2% vs. 11.4%, p<0.05). The fertilization rate of ICSI among injected oocytes was significantly higher than for IVF (72.3%±24.3% vs. 59.2%±25.9%, p<0.001), but the fertilization rate among retrieved oocytes was significantly higher in IVF than in ICSI (59.2%±25.9% vs. 52.1%±22.5%, p<0.001). Embryo quality before embryo transfer was not different between IVF and ICSI. Although the sperm parameters were not different between the first cycle and the second cycle, split insemination or ICSI was performed in 18 of the 95 cycles in which a second IVF cycle was performed.

CONCLUSION

The clinical outcomes did not differ between IVF and ICSI in split insemination cycles. Split insemination can decrease the risk of total fertilization failure. However, unnecessary ICSI is carried out in most split insemination cycles and the use of split insemination might make ICSI more common.

Influence of the insemination method on the outcomes of elective blastocyst culture

Objective

The aim of this study was to explore the effects of the insemination method on the outcomes of elective blastocyst culture.

Methods

We retrospectively analyzed the outcomes of elective blastocyst culture performed between January 2011 and December 2014.

Results

There were 2,003 cycles of conventional in vitro fertilization (IVF) and 336 cycles of intracytoplasmic sperm injection (ICSI), including 25,652 and 4,164 embryos that underwent sequential blastocyst culture, respectively. No significant differences were found in the female patients' age, basal follicle-stimulating hormone level, basal luteinizing hormone level, body mass index, number of oocytes, maturity rate, fertilization rate, or good-quality embryo rate. However, the blastocyst formation rate and embryo utilization rate were significantly higher in the conventional IVF group than in the ICSI group (54.70% vs. 50.94% and 51.09% vs. 47.65%, respectively, p<0.05). The implantation/pregnancy rate (IVF, 50.93%; ICSI, 55.10%), miscarriage rate (IVF, 12.57%; ICSI, 16.29%), and live birth rate (IVF, 42.12%; ICSI, 44.08%) were similar (p>0.05). No cycles were canceled due to the formation of no usable blastocysts.

Conclusion

Although the fertilization method had no effect on clinical outcomes, the blastocyst formation rate and embryo utilization rate in the ICSI group were significantly lower than those observed in the conventional IVF group. Therefore, more care should be taken when choosing to perform blastocyst culture in ICSI patients.

Embryonic development in human oocytes fertilized by split insemination

OBJECTIVE

To compare the laboratory outcomes of intracytoplasmic sperm injection (ICSI) and conventional insemination using sibling oocytes in poor prognosis IVF cycles where ICSI is not indicated.

METHODS

Couples undergoing IVF with following conditions were enrolled: history of more than 3 years of unexplained infertility, history of ≥3 failed intrauterine insemination, leukocytospermia or wide variation in semen analysis, poor oocyte quality, or ≥50% of embryos had poor quality in previous IVF cycle(s). Couples with severe male factor requiring ICSI were excluded. Oocytes were randomly assigned to the conventional insemination (conventional group) or ICSI (ICSI group). Fertilization rate (FR), total fertilization failure, and embryonic development at day 3 and day 5 were assessed.

RESULTS

A total of 309 mature oocytes from 37 IVF cycles (32 couples) were obtained: 161 were assigned to conventional group and 148 to ICSI group. FR was significantly higher in the ICSI group compared to the conventional group (90.5% vs. 72.7%, P<0.001). Total fertilization failure occurred in only one cycle in conventional group. On day 3, the percentage of cleavage stage embryos was higher in ICSI group however the difference was marginally significant (P=0.055). In 11 cycles in which day 5 culture was attempted, the percentage of blastocyst (per cleaved embryo) was significantly higher in the ICSI group than the conventional group (55.9% vs. 25.9%, P=0.029).

CONCLUSION

Higher FR and more blastocyst could be achieved by ICSI in specific circumstances. Fertilization method can be tailored accordingly to improve IVF outcomes.

Live birth rates using conventional in vitro fertilization compared to intracytoplasmic sperm injection in Bologna poor responders with a single oocyte retrieved

PURPOSE

To compare reproductive outcomes following conventional in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) in poor responders fulfilling the Bologna criteria, with a single oocyte retrieved.

METHODS

The present retrospective study included 243 Bologna poor responders with a single oocyte retrieved, who were categorized into three groups, depending on the fertilization method and semen quality (IVF non-male factor-IVF/NMF n = 101; ICSI non-male factor ICSI/NMF n = 50; ICSI male factor-ICSI/MF n = 92).

RESULTS

In IVF/NMF, ICSI/NMF and ICSI/MF similar fertilization rates [65.3, 66, 58.7%, respectively], proportions of embryo formation [63.4, 60, 53.3%, respectively], proportions of good quality embryos [54.7, 56.7, 57.1%, respectively], implantation rates [8.9, 10, 8.2% respectively] and live birth rates per oocyte retrieval [5.0, 4.0, 3.3%, respectively] were observed. Degeneration rate of oocytes due to mechanical damage was significantly higher after ICSI in the ICSI/NMF and ICSI/MF groups (8 and 6.5%, respectively) compared to IVF/NMF (0%) (p = 0.02).

CONCLUSIONS

Conventional IVF and ICSI are associated with similar reproductive outcomes in poor responder patients with a single oocyte retrieved. Therefore, the choice of fertilization method should be based primarily on semen quality, in combination with the patient's previous history. A randomized controlled trial should be performed to confirm this study's findings that conventional IVF and ICSI have similar reproductive outcomes in poor responders.

Can intracytoplasmic sperm injection prevent total fertilization failure and enhance embryo quality in patients with non-male factor infertility?

OBJECTIVE

To determine whether intracytoplasmic sperm injection (ICSI) could prevent total fertilization failure (TFF) and enhance the embryo quality in patients with non-male factor infertility.

STUDY DESIGN

A total of 296 in vitro fertilization (IVF) cycles performed in patients with non-male factor infertility between April 2009 and March 2013 were included in this retrospective study. During the period, ICSI and conventional IVF were performed in 142 and 154 cycles, respectively. The usual indications for ICSI were in the cycles of patients with (1) known low fertilization rate, (2) repetitive implantation failure, (3) advanced maternal age, (4) presence of endometrioma, (5) low oocyte yield (number of oocytes ≤3), or (6) poor quality oocytes. The rate of TFF, normal fertilization, abnormal pronuclei (PN) formation, embryo quality, and pregnancy outcomes between the patients treated with ICSI and conventional IVF cycles were compared.

RESULTS

The patients treated with ICSI (ICSI group, n=142) presented fewer number of oocytes than patients treated with conventional IVF cycles (n=154). The TFF rate was not different (4.2% vs. 0.6%, P=0.059), but the ICSI group presented a significantly higher rate of normal fertilization (83.4% vs. 79.1%, P=0.04) and lower rate of abnormal PN formation (3.9% vs. 13.3%, P<0.01). The cleavage stage embryo quality was better in the ICSI group (grade A: 31.1% vs. 21.3%, P=0.001; grade A+B: 65.1% vs. 47.6%, P<0.001).

CONCLUSION

The result of this study does not support the use of ICSI to prevent TFF in patients with non-male factor infertility. However, ICSI improved the fertilization rate and the embryo quality.

Comparison of the Outcome of Conventional in vitro Fertilization and Intracytoplasmic Sperm Injection in Moderate Male Infertility from Ejaculate

Objective: To evaluate whether couples with moderate male infertility should be treated with conventional in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Patients and Methods: A total of 249 couples with moderate male infertility undergoing their first IVF/ICSI cycle were enrolled in the study. The couples were divided into two groups according to the results of semen analysis: moderate oligozoospermia (O group) and moderate oligoasthenozoospermia (OA group). Sibling oocytes were randomized into groups to be inseminated either by conventional IVF or ICSI. Fertilization rate, embryo quality, implantation rate, and clinical pregnancy rate were examined. Results: There was no difference in the fertilization, implantation, and pregnancy rates between conventional IVF and ICSI in either the O group or OA group (p > 0.05). Additionally, in the OA group, the good quality embryo rate was similar after IVF or ICSI (p > 0.05). However, in the O group, the good quality embryo rate was significantly higher after ICSI than after IVF (p < 0.05). Conclusions: Couples with moderate oligozoospermia or moderate oligoasthenozoospermia did not influence the major indices of IVF. Because of the uncertainties concerning the safety of ICSI, couples with moderate oligozoospermia or moderate oligoasthenozoospermia need not be subjected to this procedure.

Conventional IVF as a laboratory strategy to rescue fertility potential in severe poor responder patients: the impact of reproductive aging

OBJECTIVE

To investigate whether laboratory strategies can improve in vitro fertilization (IVF) outcome in poor responder patients. We compared the effectiveness of conventional IVF and intra cytoplasmic sperm injection (ICSI) in assisted reproductive technologies cycles in which only one or two oocytes were retrieved at ovarian pick up, in the absence of male infertility.

DESIGN

Retrospective analysis of 425 cycles in 386 poor responder patients.

INTERVENTION(S)

Standard stimulation protocol with gonadotropins and gonadotropin releasing hormone (GnRH) antagonist.

MAIN OUTCOME MEASURE(S)

Fertilization rate, cleavage rate, good-quality embryo rate, implantation rate, clinical pregnancy rate (PR) and miscarriage rate.

RESULTS

IVF was found to be more advantageous for implantation and PR, especially in patients under 35 years and in women aged between 35 and 38 years. No differences were noted in the other parameter evaluated. Patients aged over 38 years showed no difference using the two techniques.

CONCLUSION

The employment of ICSI in the absence of a male factor can reduce reproductive outcome in poor responder. Probably because of aging-related defects overcoming the advantage of sperm selection, the choice of IVF technique is not relevant to reproductive success when oocyte quality is compromised by reproductive aging. Although further randomized trials are needed to confirm our results, we propose that, in absence of male infertility, conventional IVF might be the technique of choice in young patients, especially in those aged below 35 years.

Should few retrieved oocytes be as an indication for intracytoplasmic sperm injection?

OBJECTIVE

To reevaluate whether relatively few oocytes obtained in one cycle are an indication for intracytoplasmic sperm injection (ICSI).

METHODS

A total of 406 cycles with three or fewer retrieved oocytes performed in 396 non-male infertile couples were retrospectively reviewed. Cycles were classified into three groups by different fertilization techniques: the in vitro fertilization (IVF) group, insemination with conventional IVF; the ICSI group, insemination with ICSI though semen parameters were normal; and the rescue ICSI group, re-insemination with ICSI after conventional IVF failure.

RESULTS

The ICSI group resulted in higher normal fertilization compared with the conventional IVF group. Correspondingly, the cycle cancellation rate was decreased in the ICSI group, though it was not statistically significant. The clinical pregnancy rate and implantation rate were lower in the ICSI group compared with the conventional IVF group. Rescue ICSI was a method to avert total fertilization failure in conventional IVF, increasing fertilization and ensuring embryo availability for transfer, but the normal fertilization was the lowest due to delayed insemination and the chance of pregnancy was very little.

CONCLUSIONS

Obtaining only few oocytes in one cycle is not considered as an indication for ICSI when the sperm sample is apparently normal. Rescue ICSI is either not recommended if conventional insemination fails. Such patients should not be subjected to the unnecessary costs and potential risks of ICSI.

Should ICSI be recommended routinely in patients with four or fewer oocytes retrieved?

PURPOSE

To determine if patients with a low response to controlled ovarian hyperstimulation during IVF benefit from intracytoplasmic sperm injection (ICSI) METHODS: Retrospective analysis of 350 IVF cycles in which four or fewer oocytes were retrieved. Severe male factor cases were excluded from analysis. Conventional insemination (CI) and ICSI were compared, with primary outcome measures of fertilization rate, implantation rate, clinical pregnancy rate per embryo transfer, and pregnancy loss rate.

RESULT(S)

Fertilization rates per oocyte retrieved for CI and ICSI were comparable (51.5% vs. 51.8%). Parallel implantation rates (22% vs. 25%), clinical pregnancy rates (32.8% vs. 33.3%), and loss rates (26.7% vs. 39.5%) were also noted. No difference in cancelled cycles was reported.

CONCLUSION(S)

Our results demonstrate that in the presence of normal semen parameters, low egg number is not an indication to perform ICSI.

Comparison of IVF and ICSI when only few oocytes are available for insemination

The aim of this work was to evaluate the efficiency of IVF and intracytoplasmic sperm injection (ICSI) when few eggs available for insemination. A total of 601 women (group A, mean age 31.2 +/- 2.8 years) who were undergoing a total of 671 assisted reproduction cycles donated their excess oocytes to 694 patients (group B, mean age 41.0 +/- 0.2) for 1606 replacement cycles. Each recipient received three to five eggs. The recipients were divided into two groups depending on the insemination method used (IVF, group B1; or ICSI, group B2); ICSI patients were then subdivided into two further groups based on the semen parameters: B2A adequate for IVF and B2B only suitable for ICSI. The results showed that, when comparing A versus B and B1 versus B2, no significant differences were found in terms of pregnancy (28.0 versus 24.1% and 25.5 versus 21.4%), implantation (15.6 versus 14.9% and 15.9 versus 13.1%) and miscarriage (15.4 versus 20.5% and 17.9 versus 26.3) rates respectively. Comparing subgroups B2A and B2B, no significant differences were found in terms of pregnancy (20.0 versus 21.9%), implantation (14.4 versus 12.7%) and miscarriage rates (18.2 versus 28.6%) respectively. In conclusion, ICSI does not seem to yield better outcomes.

Comparison of ICSI and conventional IVF in patients with increased oocyte immaturity

Using sibling oocytes, the objective of this study was to compare the intracytoplasmic sperm injection (ICSI) fertilization rates to those achieved with conventional IVF in patients with high rates of oocyte immaturity. This study was observational in nature, and included 91 patients who were treated using split insemination techniques. The fertilization rates for the ICSI group and the IVF group were 41.1 +/- 15.0% and 53.2 +/- 19.8%, respectively (P &lt: 0.0001). There was no significant difference in day-3 embryo quality between the two groups. There was a significantly higher number of embryos frozen in the IVF group than in the ICSI group: 357 (84.8%) and 297 (76.7%), respectively (P = 0.037). Furthermore, the number of embryos either transferred or frozen was significantly higher in the IVF group than the ICSI group: 459 of 1173 (39.1%) and 385 of 1268 (30.4%), respectively (P < 0.0001). These data indicate that conventional IVF results in a higher fertilization rate than ICSI. Furthermore, IVF provided more embryos available for transfer or cryopreservation when compared with ICSI, thereby optimizing the patient's cycle.

Comparison of embryo quality between intracytoplasmic sperm injection and in vitro fertilization in sibling oocytes

BACKGROUND

The aim of the present study was to compare the quality of embryos derived from sibling oocytes by in vitro fertilization (IVF) or ICSI.

METHODS

Consecutive patients with a less than 40% fertilization rate in a previous standard IVF cycle or with relative male factor infertility were recruited for the study. The oocytes retrieved from each patient were divided into two groups for either conventional insemination (group A) or ICSI (group B). Power analysis showed that to detect a 25% difference in the rate of high-quality embryos between the groups with a power of 0.8, at least 1,200 oocytes were needed in each group.

RESULTS

One hundred seventy-seven patients were included in the study. Group A was comprised of 1,526 oocytes and group B of 1,480 sibling oocytes. As expected, the fertilization rate was significantly higher in group B than group A (67.1 vs. 43.6%, p < 0.001). No significant between-group differences were observed in cleavage rate (92.7 and 89.7%, respectively) and the rate of either grade A embryos (22.6 and 23.9%, respectively) or grade A(1) embryos (37.3 and 33.5%, respectively). However, in the subgroup of patients with relative male-factor infertility (n = 36), the rate of grade A(1) embryos was significantly higher in the IVF than the ICSI group (46.4 vs. 29.0%, respectively, p = 0.02).

CONCLUSIONS

Embryo quality does not seem to be influenced by the mode of fertilization (IVF or ICSI). We assume that embryo quality depends on intrinsic factors of the gametes involved rather than on the fertilization process per se.

Sibling oocyte submission to IVF and ICSI in unexplained infertility patients: a potential assay for gamete quality

In order to reduce total fertilization failure in unexplained infertility, sibling oocytes were submitted to both conventional IVF and intracytoplasmic sperm injection (ICSI). Two groups of ICSI embryos were compared in unexplained infertility patients: those derived from ICSI when IVF had failed to fertilize, and those derived from ICSI while their sibling oocytes were fertilized by IVF. The outcome of oocytes fertilized exclusively by ICSI (essential ICSI, n = 749) was compared with those fertilized both by IVF and ICSI (non-essential ICSI, n = 957) in all IVF patients treated for unexplained infertility at the Hadassah Hospital (1999-2002). The latter group was further subdivided into ICSI and IVF embryos. Total fertilization rate was 54%. Fertilization rates by ICSI were lower in the essential ICSI compared with the non-essential ICSI group, at 65 and 73% (P < 0.025). Pregnancy rates per embryo transfer in the essential ICSI group (49%), ICSI derived embryos group (55%) and IVF derived embryos (44%) from the non-essential ICSI group, were similar. Implantation rates were lower in the essential ICSI group as compared with the non-essential ICSI group (21 versus 32% respectively; P < 0.05) and 26% for IVF embryos. In conclusion, essential ICSI was associated with lower fertilization and implantation rates.

A prospective randomized trial of conventional in vitro fertilization versus intracytoplasmic sperm injection in unexplained infertility

PURPOSE

To compare outcomes in patients with unexplained infertility undergoing conventional in vitro fertilization (IVF) versus intracytoplasmic sperm injection (ICSI).

METHODS

Sixty women with unexplained infertility in a Canadian tertiary-level clinic were randomized to IVF or ICSI. Subjects underwent downregulation with gonadotropin-releasing hormone agonist prior to initiation of recombinant human follicle-stimulating hormone. The primary outcome measure was fertilization rate. Secondary outcomes included implantation rate, embryo quality, clinical pregnancy rate, and live birth rate.

RESULTS

There was no statistically significant difference in fertilization rate (77.2% IVF vs. 82.4% ICSI), implantation rate (38.2% IVF vs. 44.4% ICSI), clinical pregnancy rate (50% in each group), or live birth rate (46.7% IVF vs. 50% ICSI). There were two cases of failed fertilization in the IVF group. There was no significant difference in embryo quality between groups.

CONCLUSIONS

There were no differences in clinical outcomes associated with IVF versus ICSI in the treatment of unexplained infertility.

Intracytoplasmic sperm injection as a treatment for unexplained total fertilization failure or low fertilization after conventional in vitro fertilization

OBJECTIVE

To determine whether IVF or intracytoplasmic sperm injection (ICSI) should be the choice of treatment in case of a previous IVF attempt with unexplained total fertilization failure or low fertilization (<25%).

DESIGN

Prospective study.

SETTING

Leiden University Medical Center.

PATIENT(S)

Thirty-eight couples undergoing IVF and ICSI on sibling oocytes after a first IVF attempt with total fertilization failure or with low fertilization (<25%).

INTERVENTION(S)

Performing IVF and ICSI on sibling oocytes.

MAIN OUTCOME MEASURE(S)

Fertilization and (ongoing) pregnancy rate.

RESULT(S)

A total of 271 oocytes were collected in 24 oocyte retrievals in the total fertilization failure group. Hundred nine oocytes were randomly allocated to IVF and 12 were fertilized (11%); 162 sibling oocytes were allocated to ICSI and 78 were fertilized (48%). In 8 of the 24 patients fertilization occurred after IVF. The pregnancy rate after transfer of 1 IVF and 1 ICSI embryo (n = 3) was 67% and after the transfer of 2 ICSI embryos (n = 21) this was 52%. In the low fertilization group 169 oocytes were collected in 14 oocyte retrievals. Seventy-two oocytes were randomly allocated to IVF and 16 were fertilized (22%). Ninety-seven sibling oocytes were allocated to ICSI and 58 were fertilized (60%). In 7 of 14 patients fertilization occurred after IVF. The pregnancy rate after the transfer of 1 IVF and 1 ICSI embryo (n = 5) was 80% and after the transfer of 2 ICSI embryos (n = 9) this was 33%.

CONCLUSION(S)

Performing ICSI on some oocytes of a cohort may avoid total fertilization failures both in patients with a history of total fertilization failure and in patients with a history of low fertilization, as the percentage of fertilization is higher after ICSI compared to IVF and the recurrence of total fertilization failure and low fertilization is high after IVF treatment.

The role of cytokines in endometriosis

PROBLEM

To review the literature on the role of peritoneal cytokines in the pathogenesis and endometriosis-related infertility.

METHODS OF STUDY

A MEDLINE search was conducted by the key words of cytokine and endometriosis in the English publications, and references identified within the identified papers were also reviewed.

RESULTS

Several cytokines including interleukin (IL)-1, 6, 8, 10, tumor necrosis factor (TNF)-alpha, and vascular endothelial growth factor (VEGF) were reported to be increased in the peritoneal fluid (PF) of women with endometriosis. Those cytokines may be involved in macrophage activation, inflammatory change and enhanced angiogenesis. However, some cytokines were less expressed such as IL-2, and interferon (IFN)-gamma. They reflect the impaired T- and natural killer (NK)-cell function. Endometriotic implants produce some factors, e.g. matrix metalloproteinases (MMPs), Bcl-2, and affect their capacity to implant into the peritoneum.

CONCLUSION

Peritoneal cytokines, which are produced by mesothelial cells, leukocytes and ectopic endometrial cells, interwork locally and systemically in women with endometriosis. More studies about the specific role and interactions of these cytokines are needed to improve the understanding of endometriosis and to develop novel therapies.

Intracytoplasmic sperm injection: stiletto conception or a stab in the dark

To describe the importance of molecular and cellular analyses in intracytoplasmic sperm injection (ICSI) the authors review the literature on biological challenges in ICSI and associated techniques. Several matters can be proposed in molecular and cellular challenges in ICSI for safety and efficacy: (1) a reliable and convenient animal model for understanding the molecular and cellular basis of human ICSI must be established, and molecular and cellular analysis of the first cell cycle of human fertilization should be better understood; (2) a proper assay for human sperm function that contributes to the indication for ICSI should be developed; and (3) de novo and transmitted genetic security in ICSI should be examined.

Fertilization rate and preimplantation development after intracytoplasmic sperm injection

Intracytoplasmic sperm injection (ICSI) is the treatment of choice in cases of male factor infertility. In the present review, all data from the literature regarding early fertlilization and preimplantation embryo development are analysed. ICSI seems to offer better fertilization rates than conventional IVF, even in the absence of a male factor and in prospective, randomized studies on sibling oocytes. Blastocyst formation is lower in ICSI than in IVF. This may be due to sublethal disturbances in oocyte architecture and function. Implantation and pregnancy rates, however, are similiar in ICSI and conventional IVF. Therefore, it can be concluded that ICSI offers a safe approach, as far as is known to date, for the treatment of male factor infertility. Embryo selection in cases of sublethal damage to oocytes seems to take place in the early preimplantation stages. Nor does the risk of monozygotic twinning, which was also proposed to be higher in ICSI compared with conventional IVF, seem to increase with this procedure.

Performing ICSI using an injection pipette with the smallest possible inner diameter and a long taper increases normal fertilization rate, decreases incidence of degeneration and tripronuclear zygotes, and enhances embryo development

PURPOSE

To compare the efficacy of two types of injection pipette used for ICSI, one with a larger (5-7 microns) inner diameter and a shorter taper with that inner diameter, and another with the smallest (3-5 microns) possible inner diameter and a longer taper with that inner diameter.

METHODS

Retrieved oocytes at metaphase II stage were injected using one of two types of injection pipette, in 33 and 94 cycles, respectively, in a total of 127 cycles in 108 patients.

RESULTS

In comparison to the injection pipette with a larger (5-7 microns) inner diameter and a shorter taper with that inner diameter, the injection pipette with the smallest (3-5 microns) possible inner diameter and a longer taper with that inner diameter increased normal fertilization rate ((70 +/- 3.6)% vs. (86 +/- 2.2)%; P = .001; mean +/- SEM); decreased the incidence of degeneration ((14 +/- 2.4)% vs. (5 +/- 1.4)%; P = .001) and tripronuclear zygotes ((1.0 +/- 0.35)% vs. (0.1 +/- 0.21)%; P = .03); increased Day-2 diploid embryos ((69 +/- 3.7)% vs. (85 +/- 2.2)%; P = .001) and good-quality Day-2 diploid embryos ((67 +/- 4.0)% vs. (79 +/- 2.4)%; P = .03), all per injected oocyte; and increased the number of blastomeres per good-quality Day-2 diploid embryo ((3.0 +/- 0.21 vs. 3.8 +/- 0.12; P = .0003).

CONCLUSIONS

Performing ICSI using an injection pipette with the smallest (3-5 microns) possible inner diameter and a longer taper with that inner diameter maximizes normal fertilization rate, minimizes the incidence of postinjection degeneration and tripronuclear zygotes, and enhances embryo development.

The status of controlled prospective clinical trials for efficacy of intracytoplasmic sperm injection in in vitro fertilization for non-male factor infertility

PURPOSE

Intracytoplasmic sperm injection (ICSI) of some sibling oocytes may have a beneficial effect in couples going through in vitro fertilization for causes of infertility not related to the male factor. Our purpose was to critically appraise the randomized controlled studies done in this area and arrive at some recommendations.

METHODS

The four controlled trials done so far have utilized similar methodology, i.e., they randomly allotted sibling oocytes to ICSI versus standard insemination in patients going through in vitro fertilization and embryo transfer.

RESULTS

In the first trial reported in 1995 there was no difference in fertilization rate, whereas the later trials reported in 1997, 1999, and 2000 showed improvement with ICSI that reached statistically significant level in the last two studies.

CONCLUSIONS

Total fertilization failure of an in vitro fertilization cycle can be prevented and fertilization can be improved if half of sibling oocytes are subjected to ICSI.