Conventional in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI): which is preferred for advanced age patients with five or fewer oocytes retrieved?

The impact of intracytoplasmic sperm injection versus conventional in vitro fertilization on the reproductive outcomes of couples with non-male factor infertility and frozen-thawed embryo transfer cycles

This study was aimed to investigate the impact of intracytoplasmic sperm injection (ICSI) on reproductive outcomes in couples with non-male factor infertility and frozen-thawed embryo transfer (FET) treatment. This retrospective cohort study involved a total of 10,143 cycles from 6206 couples who underwent FET at the Third Affiliated Hospital of Zhengzhou University between January 2016 and September 2022. Patients were categorized into two groups based on the insemination methods of transferred embryos. Clinical and neonatal outcomes were compared between ICSI and conventional in vitro fertilization (cIVF) groups. The results showed that ICSI was not associated with improved clinical outcomes compared to cIVF. However, ICSI was associated with lower birthweight when twins were born. In conclusion, although subgroup analysis showed that ICSI was associated with slightly improved live birth rate for infertile couples with non-male factor infertility compared to cIVF, the regression analysis showed that ICSI did not demonstrate any improvement of the reproductive outcomes. The infertile women with twin pregnancies should be further informed of the lower birthweight and lower birth length when their oocytes were inseminated with ICSI. The findings of this study provide valuable insights for clinicians when discussing the benefits and risks of ICSI in patients with non-male factor infertility.

Reproductive Outcomes of Conventional In Vitro Fertilization and Intracytoplasmic Sperm Injection in Patients with Non-Severe Male Infertility Across Poor and Different Sub-Optimal Ovarian Response Categories: A Cohort Study Based on 30,352 Fresh Cycles from 2009-2019

Due to the influence of economic, social and many other factors, there are more and more reproductive problems. Originally introduced for managing male factor infertility, intracytoplasmic sperm injection had become the most commonly used fertilization treatment in the world, with broadened indications including low oocyte yield, prior fertilization failure with conventional in vitro fertilization etc. However, academic evidence for better live-birth outcomes of intracytoplasmic sperm injection over conventional in vitro fertilization is limited. Thus, we aimed to compare the reproductive outcomes of conventional in vitro fertilization and intracytoplasmic sperm injection in patients with non-severe male factor infertility across poor and different sub-optimal ovarian response categories. The fertility rate, implantation rate, clinical pregnancy rate, live birth rate and other obstetric outcomes were mainly compared. Our results showed that independent of the number of oocytes retrieved, intracytoplasmic sperm injection significantly increased the fertilization rate, while conventional in vitro fertilization cycles showed a higher implantation rate, clinical pregnancy rate, and live birth rate. No differences were observed in most obstetric outcomes. Our study indicates that poor ovarian response is not an indication for intracytoplasmic sperm injection in couples with non-severe male infertility.

Intracytoplasmic sperm injection vs. in-vitro fertilization in couples in whom the male partners had a semen analysis within normal reference ranges: An open debate

During recent decades, the application of intracytoplasmic sperm injection has increased considerably worldwide, especially in couples with non-male factor infertility. However, several studies analyzing the broad use of intracytoplasmic sperm injection, even in cases with a normal semen analysis, have collectively demonstrated no benefits compared to conventional in-vitro fertilization. Currently, there is insufficient evidence to support the intracytoplasmic sperm injection technique vs. in-vitro fertilization in cases of poor ovarian response or a low number of oocytes collected, or in patients with advanced maternal age. Since the intracytoplasmic sperm injection technique is more operator-dependent and invasive, its use should only be recommended in cases of male-factor infertility. There is some evidence showing that intracytoplasmic sperm injection is linked with an increased risk of birth defects. Albeit this evidence is limited, and currently it is not possible to draw a firm conclusion on these concerns, we do believe that these risks should be rigorously investigated. Thus, this review aims to clarify the debate on the application of the intracytoplasmic sperm injection procedure, as compared to standard in-vitro fertilization, in those assisted reproductive technology cycles without a clear male factor infertility. Furthermore, we try to clarify whether intracytoplasmic sperm injection would result in a higher live birth rate than in-vitro fertilization, in couples with non-male factor infertility.

Comparisons of conventional in vitro fertilization versus intracytoplasmic sperm injection in women with thyroid autoimmunity and non-male factor infertility, a propensity score matching analysis

The aim of the study is to compare the outcomes between the insemination methods of conventional in vitro fertilization and intracytoplasmic sperm injection in infertile women with thyroid autoimmunity and non-male factor infertility. This was a retrospective cohort study which included women with thyroid autoimmunity and non-male factor infertility. Reproductive outcomes such as embryo development parameters and clinical outcomes were compared between the two groups. The propensity score matching was applied to balance the general characteristics with significant differences between the two groups. Generalized estimating equations were used to explore the impact of ICSI on the embryo development potential of the inseminated oocytes. Sensitivity analysis using E-values was used to account for unknown confounders. After 1:2 propensity score matching, the general characteristics were all comparable. The good cleavage embryo rate, blastocyst utilization rate, and good blastocyst rate were significantly lower in the intracytoplasmic sperm injection group than those in the conventional in vitro fertilization group. After controlling for the confounding factors, intracytoplasmic sperm injection was significantly negatively associated with development of usable blastocysts and good blastocysts, while showed no impact on fertilized oocytes, usable cleavage embryos and good cleavage embryos. Although limited by the limited sample size, there were comparable clinical and obstetrical outcomes between conventional in vitro fertilization and intracytoplasmic sperm injection groups. Intracytoplasmic sperm injection neither improved the embryo development potential nor increased the clinical pregnancy and live birth rates compared to conventional in vitro fertilization in the studied population. Prospective studies that randomly divide the studied population in two the two groups and compare the reproductive outcomes are warranted.

Conventional IVF is feasible in preimplantation genetic testing for aneuploidy

PURPOSE

To investigate the feasibility of the application of conventional in vitro fertilization (cIVF) for couples undergoing preimplantation genetic testing for aneuploidies (PGT-A) with non-male factor infertility.

METHODS

To evaluate the efficiency of sperm whole-genome amplification (WGA), spermatozoa were subjected to three WGA protocols: Picoplex, ChromInst, and multiple displacement amplification (MDA). In the clinical studies, 641 couples who underwent PGT-A treatment for frozen embryos between January 2016 and December 2021 were included to retrospectively compare the chromosomal and clinical outcomes of cIVF and intracytoplasmic sperm injection (ICSI). Twenty-six couples were prospectively recruited for cIVF and PGT-A treatment between April 2021 and April 2022; parental contamination was analyzed in biopsied samples; and 12 aneuploid embryos were donated to validate the PGT-A results.

RESULTS

Sperm DNA failed to amplify under Picoplex and ChromInst conditions but could be amplified using MDA. In frozen PGT-A cycles, no significant differences in the average rates of euploid, mosaic, and aneuploid embryos per cycle between the cIVF-PGT-A and ICSI-PGT-A groups were observed. The results of the prospective study that recruited couples for cIVF-PGT-A treatment showed no paternal contamination and one case of maternal contamination in 150 biopsied trophectoderm samples. Among the 12 donated embryos with whole-chromosome aneuploidy, 11 (91.7%) presented uniform chromosomal aberrations, which were in agreement with the original biopsy results.

CONCLUSIONS

Under the Picoplex and ChromInst WGA protocols, the risk of parental contamination in the cIVF-PGT-A cycles was low. Therefore, applying cIVF to couples with non-male factor infertility who are undergoing PGT-A is feasible.

Associations between Urinary Concentrations of Disinfection Byproducts and in Vitro Fertilization Outcomes: A Prospective Cohort Study in China

BACKGROUND

Experimental studies show that disinfection byproducts (DBPs) can inhibit oocyte maturation, decrease fertilization capacity, and impair embryo development, but human evidence is lacking.

OBJECTIVES

We aimed to evaluate the associations between exposure to drinking water DBPs and in vitro fertilization (IVF) outcomes.

METHODS

The study included 1,048 women undergoing assisted reproductive technology (ART) treatment between December 2018 and January 2020 from a prospective cohort study, the Tongji Reproductive and Environmental study in Wuhan, China. Exposure to DBPs was assessed by dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) in up to four urine samples, which were collected on the day of both enrollment and oocyte retrieval. Multivariable generalized linear mixed models, accounting for multiple IVF cycles per woman, were applied to evaluate the associations between urinary biomarkers of DBP exposures and IVF outcomes. Stratified analyses were used to explore the potential effect modifiers.

RESULTS

The included 1,048 women underwent 1,136 IVF cycles, with 960 (91.6%), 84 (8.0%), and 4 (0.4%) women contributing one cycle, two cycles, and three cycles, respectively. We found that elevated quartiles of urinary DCAA and TCAA concentrations were associated with reduced numbers of total oocytes and metaphase II oocytes and that urinary DCAA concentrations with a lower proportion of best-quality embryos (all p for trends < 0.05 ). Moreover, elevated quartiles of urinary DCAA concentrations were associated with decreased proportions of successful implantation, clinical pregnancy, and live birth (14%, 15%, and 15% decreases in adjusted means comparing the extreme quartiles, respectively; all p for trends < 0.05 ). Stratification analyses showed that the inverse associations of urinary TCAA concentrations with multiple IVF outcomes were stronger among women ≥ 30 y of age (p for interactions < 0.05 ).

DISCUSSION

Exposure to drinking water DBPs was inversely associated with some IVF outcomes among women undergoing ART treatment. Further study is necessary to confirm our findings. https://doi.org/10.1289/EHP12447.

Application of conventional IVF during preimplantation genetic testing for aneuploidies: a feasibility study

RESEARCH QUESTION

Is it feasible to apply conventional IVF to couples undergoing preimplantation genetic testing for aneuploidies (PGT-A) with non-severe male infertility?

DESIGN

The last wash fluid of biopsied trophectoderm (TE) cells was collected for whole genome amplification (WGA). A method was developed to determine parental contamination. Using single-nucleotide polymorphism (SNP) analysis, two standard curves were established; further mixtures were used for verification. Finally, 29 WGA products from couples undergoing conventional IVF were used to evaluate parental contamination.

RESULTS

The WGA results of the last wash fluid of biopsied TE cells revealed almost no free DNA. By adopting two strategies based on maternally and paternally biased SNP in the mixture, data from bioinformatics analysis were analysed to determine the relationship between maternal (Index M) and paternal (Index F) bias statistics. Two standard curves were successfully established based on these indices that allowed the prediction of maternal and parental contamination, which correlated well with actual ratios of known composition mixtures during validation. The average contamination level was 10.6% determined from 10 WGA products that featured maternal contamination, whereas that of the other 19 products that featured paternal contamination was less than 10%.

CONCLUSIONS

This study confirmed the feasibility of applying conventional IVF to couples undergoing PGT-A with non-severe male infertility.

Calcium ionophore improves embryonic development and pregnancy outcomes in patients with previous developmental problems in ICSI cycles

BACKGROUND

Calcium (Ca²⁺) ionophores are now mainly considered as efficient treatments for fertilization failure. Recently, its application for rescuing poor embryo development was proposed but still non-routine. This study aimed to explore whether Ca²⁺ ionophore improves embryo development and pregnancy outcomes in patients with poor embryo development in previous intracytoplasmic sperm injection (ICSI) cycles.

METHODS

This study included 97 patients undergoing assisted oocyte activation (AOA) with Ca²⁺ ionophore (calcimycin, A23187) treatment. Preimplantation embryonic development and clinical outcomes were compared between ICSI-AOA cycles (AOA group) and previous ICSI cycles of the same patients in which poor embryo developmental potential was present (non-AOA group). Subgroups stratified by maternal age (< 35, 35-40, ≥ 40 years, respectively) were analyzed separately.

RESULTS

A total of 642 MII oocytes were collected in AOA group, and 689 in non-AOA group. Significantly higher day 3 good quality embryo rate (P = 0.034), good quality blastocyst formation rate (P <  0.001), and utilization rate (P <  0.001) were seen in AOA group. Similar results were seen in each subgroup. For pregnancy outcomes, there were significant differences in clinical pregnancy rate (P = 0.039) and live birth rate (P = 0.045) in total group. In subgroup aged < 35 years, biochemical (P = 0.038), clinical (P = 0.041), and ongoing pregnancy rate (P = 0.037) in AOA group were significantly higher than that in non-AOA group. No significant improvement for clinical outcomes for subgroups aged 35-40 and aged ≥40.

CONCLUSION

The study suggests that calcimycin could improve preimplantation development and pregnancy outcomes in patients aged < 35 years with embryo developmental problems in previous ICSI cycles.

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.

Opportunities and Limits of Conventional IVF versus ICSI: It Is Time to Come off the Fence

Conventional IVF (c-IVF) is one of the most practiced assisted reproductive technology (ART) approaches used worldwide. However, in the last years, the number of c-IVF procedures has dropped dramatically in favor of intracytoplasmic sperm injection (ICSI) in cases of non-male-related infertility. In this review, we have outlined advantages and disadvantages associated with c-IVF, highlighting the essential steps governing its success, its limitations, the methodology differences among laboratories and the technical progress. In addition, we have debated recent insights into fundamental questions, including indications regarding maternal age, decreased ovarian reserve, endometriosis, autoimmunity, single oocyte retrieval-cases as well as preimplantation genetic testing cycles. The “overuse” of ICSI procedures in several clinical situations of ART has been critically discussed. These insights will provide a framework for a better understanding of opportunities associated with human c-IVF and for best practice guidelines applicability in the reproductive medicine field.

Monopronucleated (1PN) and tripronuclear (3PN) zygotes formation during assisted reproduction in POSEIDON group 4 patients: Emphasizing on polar bodies

AIM

Abnormal fertilization (1PN/3PN) and its accompanying polar body (PB) conditions have been less discussed in poor ovarian responders. By observing the PBs, we analyzed the mechanisms of abnormal fertilization and aimed to explore the role of intracytoplasmic sperm injection/in vitro fertilization (ICSI/IVF) in POSEIDON group 4 patients.

METHODS

An observational study. All fresh IVF/ICSI cycles from January 2018 to December 2019 were evaluated. The inclusion criteria were POSEIDON group 4. Fertilization and PB conditions were assessed 16-18 h post-insemination. Primary observation endpoints including normal fertilization, abnormal fertilization, and total fertilization failure rate.

RESULTS

A total of 351 cycles involving 180 patients met the inclusion criteria. Of these, 15 cycles reported no retrieved oocytes. Finally, 336 cycles (IVF, n = 267; ICSI, n = 69) were included. A total of 1005 oocytes and 939 embryos were assessed. The mean female age was 40.8 years, and the mean AMH level was 0.6 ng/mL. The normal fertilization rate was 69.7%. The zygote distribution was 18.7% 0PN, 3.9% 1PN, 66.9% 2PN, 9.5% 3PN, and 1.0% ≥4PN. For 1PN zygotes, 59% were denoted as 1PN2PB. The mean 3PN rate was 8.9%.

CONCLUSIONS

In POSEIDON group 4, most of the monopronucleated zygotes were 1PN2PB. Digyny (3PN1PB), due to failure to extrude the second PB, was the major cause of triploidy in which ICSI could not circumvent. The distribution of abnormally fertilized zygotes was similar in IVF and ICSI. To investigate the mechanisms of abnormal fertilization and assess whether ICSI is necessary, analysis of PB will provide important clues.

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.

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.

Conventional IVF revisited: Is ICSI better for non-male factor infertility? Randomized controlled double blind study

STUDY QUESTION

Is ICSI better than conventional IVF for non-male factor infertility?

SUMMARY ANSWER

IVF should be the choice of assisted reproductive technique in non-male factor infertility cases.

WHAT IS ALREADY KNOWN

Although total fertilization failure is a major concern for patients and professionals, the overall risk/benefit analysis favors conventional IVF in non-male factor infertility cases. However, according to the ESHRE EIM database pertaining to 1997-2012, the use of IVF has been continuously decreasing in favor of ICSI.

STUDY DESIGN, SIZE, DURATION

Randomized controlled double-blind study involving 138 women undergoing ART in a private Center.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All couples with a female partner ≤42 years of age and without severe male factor (total progressive motile sperm with normal morphology >10.000) were included in the study. Exclusion criteria were: history of total fertilization failure, less than 6 cumulus oocyte complexes (COC) available for fertilization, prenatal genetic testing (PGT) cycles, unwillingness to participate and couples undergoing total cryopreservation for any indication. On the day of oocyte pick up, sibling COCs were randomly allocated to fertilization with IVF or denudation followed by ICSI to MII oocytes. The decision to transfer IVF or ICSI embryo(s) depended on embryo quality. Women receiving two embryos were given only IVF or ICSI embryos. Neither the clinician performing the transfer nor the patients were aware of the fertilization method used to generate the embryos transferred. Main outcome parameters were fertilization, clinical pregnancy, implantation and miscarriage rates.

MAIN RESULTS AND THE ROLE OF CHANCE

Demographic variables, ovarian reserve and infertility etiology, duration of stimulation, total gonadotropin consumption, peak estradiol levels were similar for IVF-ET and ICSI-ET groups. Mean number of COCs (18.95 vs 19.24), number of embryos transferred (1,81 vs 1,81), the ratio of good quality embryos/total embryos (56.89 % and 55.97 %), clinical pregnancy rates (63 % vs 49 %), implantation rates (31 % vs 28 %), and abortion rates (12,5 % vs 8,1 %) were also similar. A total of 1306 COCs were allocated for IVF while 1331 COCs were denuded for ICSI. Fertilization rate per inseminated oocyte was significantly higher in ICSI group (56,20 % vs 63,78 %). There were ten cases of total fertilization failure, all in the IVF group. Although overall fertilization rate was higher for ICSI, it was similar in both groups when cases with total fertilization failure were excluded.

LIMITATIONS, REASONS FOR CAUTION

The non-availability of live birth rates is a limitation. Randomization of sibling oocytes, not patients requires careful interpretation of pregnancy and implantation rates.

WIDER IMPLICATIONS OF THE FINDINGS

Lower cost, ease of application and similar clinical outcome makes IVF the choice of fertilization method in non-male factor infertility cases.

Comparing fertilization rates from intracytoplasmic sperm injection to conventional in vitro fertilization among women of advanced age with non-male factor infertility: a meta-analysis

OBJECTIVE

To evaluate the effectiveness of intracytoplasmic sperm injection (ICSI) in improving fertilization rates compared to conventional in vitro fertilization rates (IVF) among women aged ≥38 years with a non-male factor diagnosis.

DESIGN

Systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Women aged ≥38 years with a non-male factor diagnosis receiving IVF or ICSI.

INTERVENTION(S)

A systematic review of databases including PubMed and Embase was performed. Study protocol was registered at the International Prospective Register of Systematic Reviews. Studies were selected if they compared fertilization rates from ICSI with those from conventional IVF among women aged ≥38 years with a non-male factor infertility diagnosis. A random effects model was used. Meta-analysis of Observational Studies in Epidemiology guidelines were applied.

MAIN OUTCOME MEASURE(S)

Fertilization rate.

RESULTS

Seven studies including 8796 retrieved oocytes (ICSI: 4,369; IVF: 4,427) with mean female age ≥38 years met the inclusion criteria. There was no significant difference in fertilization rates between ICSI and conventional IVF (relative risk [RR] 0.99, 95% confidence interval [CI] 0.93-1.06; P = .8). Heterogeneity was observed between studies (I2 = 58.2; P < .05). Heterogeneity was significant (I2 = 57.1; P < .05) when cycles with prior fertilization failure were excluded; however, when analysis was restricted to poor responders (RR 1.01, 95% CI 0.97-1.05; P = .6), heterogeneity was no longer significant (I2 = 0.0; P = .5).

CONCLUSIONS

No difference was found in fertilization rates between conventional IVF and ICSI. Further studies are needed to assess the impact of ICSI in this population, controlling for other indications such as preimplantation genetic testing.