Preimplantation genetic screening for abnormal number of chromosomes (aneuploidies) in in vitro fertilisation or intracytoplasmic sperm injection

Correlations between clinical parameters, blastocyst morphological classification and embryo euploidy

OBJECTIVE

The aim of the present study was to evaluate clinical and embryo parameters to predict embryo ploidy.

METHODS

In this retrospective analysis, we studied 838 biopsied day-5 blastocysts from 219 patients in the period from May 2021 to July 2022. All embryos were morphologically classified before biopsy and were divided into two groups according to genetic test results. Euploid embryos (299) were compared with aneuploid embryos (539) based on maternal age, anti-Mullerian hormone, antral follicle count, and embryo morphology.

RESULTS

Maternal age (36.2±3.0) of euploid embryos was lower than maternal age (37.1±2.5) of aneuploid embryos (p<0.0001). AMH levels were higher (3.9±1.2) in the group of euploid embryos than in the group of aneuploid embryos (3.6±1.3, p<0.0001). However, the AFC was not different in the group of euploid embryos (15.3±6.0) compared to the group of aneuploid embryos (14.5±5.9, p=0.07). The presence of aneuploidy was negatively correlated with top embryo quality (embryos 4AA and 4AB). All euploid embryos (299) were top quality versus 331 of 539 (61.49%) aneuploid embryos (p<0.0001).

CONCLUSIONS

We found that euploid embryos were associated with lower maternal age, higher AMH levels, and higher quality embryos.

Review of Endometrial Receptivity Array: A Personalized Approach to Embryo Transfer and Its Clinical Applications

Successful outcomes of in vitro fertilization (IVF) rely on both the formation of a chromosomally normal embryo and its implantation in a receptive endometrium. Pre-implantation genetic testing for aneuploidy (PGT-A) has been widely accepted as a tool to assess the viability of an embryo. In 2011, the endometrial receptivity array (ERA) was first published as a tool to determine when the endometrium is most receptive to an embryo, commonly referred to as the "window of implantation" (WOI). The ERA uses molecular arrays to assess proliferation and differentiation in the endometrium and screens for inflammatory markers. Unlike PGT-A, there has been dissent within the field concerning the efficacy of the ERA. Many studies that contest the success of the ERA found that it did not improve pregnancy outcomes in patients with an already-good prognosis. Alternatively, studies that utilized the ERA in patients with repeated implantation failure (RIF) and transfer of known euploid embryos demonstrated improved outcomes. This review aims to describe the ERA as a novel technique, review the various settings that the ERA may be used in, such as natural frozen embryo transfer (nFET) and hormone replacement therapy frozen embryo transfer (HRT-FET), and provide a summary of the recent clinical data for embryo transfers in patients with RIF utilizing the ERA.

Preimplantation Genetic Testing for Aneuploidy for Recurrent Pregnancy Loss and Recurrent Implantation Failure in Minimal Ovarian Stimulation Cycle for Women Aged 35-42 Years: Live Birth Rate, Developmental Follow-up of Children, and Embryo Ranking

This study was aimed at exploring the benefits of preimplantation genetic testing for aneuploidy (PGT-A) in ensuring a successful pregnancy in patients with recurrent pregnancy loss (RPL) caused by an abnormal number of chromosomes in the embryo and recurrent implantation failure (RIF). Thirty-two patients who underwent PGT-A (18 in the RIF protocol and 14 in the RPL protocol) were enrolled in the study, and 2556 patients who did not undergo PGT-A during the same in vitro fertilization (IVF) treatment period were enrolled as controls. All patients underwent minimal stimulation cycle IVF. In the RPL protocol, the live birth rate per embryo transfer (ET) and that per patient were higher with PGT-A (80.0% each) than without it (0% each; P = 0.0050), and the rate of miscarriages was lower with PGT-A than without it (20.0% vs. 100.0%, P = 0.0098). In the RIF protocol, there were no significant differences in the live birth rate per ET and in the rate of miscarriages between groups with and without PGT-A-90.0% vs. 69.2% (P = 0.2313) and 0% vs. 10.0% (P = 0.3297), respectively. None of the children whose mothers underwent PGT-A presented adverse findings at a 1.5-year developmental check-up. In conclusion, PGT-A in RPL is advantageous for improving the live birth rate per ET and that per patient in minimal stimulation cycle IVF; it reduces the rate of miscarriages. In addition, PGT-A might be more beneficial for embryo selection than the existing morphological grades of blastocysts, resulting in earlier conception.

PGT-A: who and when? Α systematic review and network meta-analysis of RCTs

PURPOSE

Wide controversy is still ongoing regarding efficiency of preimplantation genetic testing for aneuploidy (PGT-A). This systematic review and meta-analysis, aims to identify the patient age group that benefits from PGT-A and the best day to biopsy.

METHODS

A systematic search of the literature was performed on MEDLINE/PubMed, Embase and Cochrane Central Library up to May 2020. Eleven randomized controlled trials employing PGT-A with comprehensive chromosomal screening (CCS) on Day-3 or Day-5 were eligible.

RESULTS

PGT-A did not improve live-birth rates (LBR) per patient in the general population (RR:1.11; 95%CI:0.87-1.42; n=1513; I2=75%). However, PGT-A lowered miscarriage rate in the general population (RR:0.45; 95%CI:0.25-0.80; n=912; I2=49%). Interestingly, the cumulative LBR per patient was improved by PGT-A (RR:1.36; 95%CI:1.13-1.64; n=580; I2=12%). When performing an age-subgroup analysis PGT-A improved LBR in women over the age of 35 (RR:1.29; 95%CI:1.05-1.60; n=692; I2=0%), whereas it appeared to be ineffective in younger women (RR:0.92; 95%CI:0.62-1.39; n=666; I2=75%). Regarding optimal timing, only day-5 biopsy practice presented with improved LBR per ET (RR: 1.37; 95% CI: 1.03-1.82; I2=72%).

CONCLUSION

PGT-A did not improve clinical outcomes for the general population, however PGT-A improved live-birth rates strictly when performed on blastocyst stage embryos of women over the 35-year-old mark.

Individualized ovarian stimulation in IVF/ICSI treatment: it is time to stop using high FSH doses in predicted low responders

In IVF/ICSI treatment, the FSH starting dose is often increased in predicted low responders from the belief that it improves the chance of having a baby by maximizing the number of retrieved oocytes. This intervention has been evaluated in several randomized controlled trials, and despite a slight increase in the number of oocytes—on average one to two more oocytes in the high versus standard dose group—no beneficial impact on the probability of a live birth has been demonstrated (risk difference, −0.02; 95% CI, −0.11 to 0.06). Still, many clinicians and researchers maintain a highly ingrained belief in ‘the more oocytes, the better’. This is mainly based on cross-sectional studies, where the positive correlation between the number of retrieved oocytes and the probability of a live birth is interpreted as a direct causal relation. If the latter would be present, indeed, maximizing the oocyte number would benefit our patients. The current paper argues that the use of high FSH doses may not actually improve the probability of a live birth for predicted low responders undergoing IVF/ICSI treatment and exemplifies the flaws of directly using cross-sectional data to guide FSH dosing in clinical practice. Also, difficulties in the de-implementation of the increased FSH dosing strategy are discussed, which include the prioritization of intermediate outcomes (such as cycle cancellations) and the potential biases in the interpretation of study findings (such as confirmation or rescue bias).

Which ovarian reserve marker relates to embryo quality on day 3 and blastocyst; age, AFC, AMH?

Objective:

The aim of the present prospective study was to evaluate which ovarian reserve marker would be more reliable as the quality of the A + B embryos (day 3 and blastocyst).

Methods:

We ran a prospective study with 124 infertile women, aged 24-48 years, from 2017 to 2018. The patients were divided into 3 groups according to age and the subgroups were compared for AMH, AFC, number of A+B embryos. New division of the 3 groups was performed based on the AMH, and the subgroups were compared for age, AFC and number of A+B embryos. Finally, we divided the patients into 3 groups, based on the AFC, and we compared the subgroups for age, AMH and number of A+B embryos. P<0.05 was considered statistically significant.

Results:

When the 124 patients were divided according to age, we found a significant fall in an A+B embryo quality (day3; blastocyst) after 35 years (p<0.038; p<0.035), and more severely after 37 years (p<0.032; p<0.027). When the 124 patients were divided according to AMH, there was a significant fall in A+B embryo quality (day 3; blastocyst), with AMH<1ng/ml (p<0.023; p<0.021). When the 124 patients were divided according to AFC, there was a significant fall in A+B embryo quality (day 3; blastocyst) with AFC<7 (p<0.025; p<0.023). These markers had significant associations with embryo quality (p<0.005).

Conclusion:

Age, AFC and AMH have significant associations with A +B embryo quality on day 3 and blastocyst.

IVF, from the past to the future: the inheritance of the Capri Workshop Group

Today IVF use is booming all over the world and has even started to play a role in demographic analyses. Prognosis-adjusted estimates suggest that up to two-thirds of couples could achieve a live birth. However, the scenario is less exciting in reality. Discontinuation during the cycles is common, and age and ovarian response continue to be crucial in modulating this rate of success. A growing interest is now given to the risk of abuses and in particular to overtreatment and to prescriptions of useless, if not harmful, expensive additional treatments ('add-ons'). A more rational, evidence-based and wise approach is needed. From a scientific perspective, several obscure aspects remain and warrant future investigations. Of particular interest are the neglected role of sperm selection, the potential adult implications of early embryo life in vitro and the issue of sustainability.

Preimplantation genetic testing for aneuploidies (abnormal number of chromosomes) in in vitro fertilisation

BACKGROUND

In in vitro fertilisation (IVF) with or without intracytoplasmic sperm injection (ICSI), selection of the most competent embryo(s) for transfer is based on morphological criteria. However, many women do not achieve a pregnancy even after 'good quality' embryo transfer. One of the presumed causes is that such morphologically normal embryos have an abnormal number of chromosomes (aneuploidies). Preimplantation genetic testing for aneuploidies (PGT-A), formerly known as preimplantation genetic screening (PGS), was therefore developed as an alternative method to select embryos for transfer in IVF. In PGT-A, the polar body or one or a few cells of the embryo are obtained by biopsy and tested. Only polar bodies and embryos that show a normal number of chromosomes are transferred. The first generation of PGT-A, using cleavage-stage biopsy and fluorescence in situ hybridisation (FISH) for the genetic analysis, was demonstrated to be ineffective in improving live birth rates. Since then, new PGT-A methodologies have been developed that perform the biopsy procedure at other stages of development and use different methods for genetic analysis. Whether or not PGT-A improves IVF outcomes and is beneficial to patients has remained controversial.

OBJECTIVES

To evaluate the effectiveness and safety of PGT-A in women undergoing an IVF treatment.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility (CGF) Group Trials Register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, and two trials registers in September 2019 and checked the references of appropriate papers.

SELECTION CRITERIA

All randomised controlled trials (RCTs) reporting data on clinical outcomes in participants undergoing IVF with PGT-A versus IVF without PGT-A were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, assessed risk of bias, and extracted study data. The primary outcome was the cumulative live birth rate (cLBR). Secondary outcomes were live birth rate (LBR) after the first embryo transfer, miscarriage rate, ongoing pregnancy rate, clinical pregnancy rate, multiple pregnancy rate, proportion of women reaching an embryo transfer, and mean number of embryos per transfer.

MAIN RESULTS

We included 13 trials involving 2794 women. The quality of the evidence ranged from low to moderate. The main limitations were imprecision, inconsistency, and risk of publication bias. IVF with PGT-A versus IVF without PGT-A with the use of genome-wide analyses Polar body biopsy One trial used polar body biopsy with array comparative genomic hybridisation (aCGH). It is uncertain whether the addition of PGT-A by polar body biopsy increases the cLBR compared to IVF without PGT-A (odds ratio (OR) 1.05, 95% confidence interval (CI) 0.66 to 1.66, 1 RCT, N = 396, low-quality evidence). The evidence suggests that for the observed cLBR of 24% in the control group, the chance of live birth following the results of one IVF cycle with PGT-A is between 17% and 34%. It is uncertain whether the LBR after the first embryo transfer improves with PGT-A by polar body biopsy (OR 1.10, 95% CI 0.68 to 1.79, 1 RCT, N = 396, low-quality evidence). PGT-A with polar body biopsy may reduce miscarriage rate (OR 0.45, 95% CI 0.23 to 0.88, 1 RCT, N = 396, low-quality evidence). No data on ongoing pregnancy rate were available. The effect of PGT-A by polar body biopsy on improving clinical pregnancy rate is uncertain (OR 0.77, 95% CI 0.50 to 1.16, 1 RCT, N = 396, low-quality evidence). Blastocyst stage biopsy One trial used blastocyst stage biopsy with next-generation sequencing. It is uncertain whether IVF with the addition of PGT-A by blastocyst stage biopsy increases cLBR compared to IVF without PGT-A, since no data were available. It is uncertain if LBR after the first embryo transfer improves with PGT-A with blastocyst stage biopsy (OR 0.93, 95% CI 0.69 to 1.27, 1 RCT, N = 661, low-quality evidence). It is uncertain whether PGT-A with blastocyst stage biopsy reduces miscarriage rate (OR 0.89, 95% CI 0.52 to 1.54, 1 RCT, N = 661, low-quality evidence). No data on ongoing pregnancy rate or clinical pregnancy rate were available. IVF with PGT-A versus IVF without PGT-A with the use of FISH for the genetic analysis Eleven trials were included in this comparison. It is uncertain whether IVF with addition of PGT-A increases cLBR (OR 0.59, 95% CI 0.35 to 1.01, 1 RCT, N = 408, low-quality evidence). The evidence suggests that for the observed average cLBR of 29% in the control group, the chance of live birth following the results of one IVF cycle with PGT-A is between 12% and 29%. PGT-A performed with FISH probably reduces live births after the first transfer compared to the control group (OR 0.62, 95% CI 0.43 to 0.91, 10 RCTs, N = 1680, I² = 54%, moderate-quality evidence). The evidence suggests that for the observed average LBR per first transfer of 31% in the control group, the chance of live birth after the first embryo transfer with PGT-A is between 16% and 29%. There is probably little or no difference in miscarriage rate between PGT-A and the control group (OR 1.03, 95%, CI 0.75 to 1.41; 10 RCTs, N = 1680, I² = 16%; moderate-quality evidence). The addition of PGT-A may reduce ongoing pregnancy rate (OR 0.68, 95% CI 0.51 to 0.90, 5 RCTs, N = 1121, I² = 60%, low-quality evidence) and probably reduces clinical pregnancies (OR 0.60, 95% CI 0.45 to 0.81, 5 RCTs, N = 1131; I² = 0%, moderate-quality evidence).

AUTHORS' CONCLUSIONS

There is insufficient good-quality evidence of a difference in cumulative live birth rate, live birth rate after the first embryo transfer, or miscarriage rate between IVF with and IVF without PGT-A as currently performed. No data were available on ongoing pregnancy rates. The effect of PGT-A on clinical pregnancy rate is uncertain. Women need to be aware that it is uncertain whether PGT-A with the use of genome-wide analyses is an effective addition to IVF, especially in view of the invasiveness and costs involved in PGT-A. PGT-A using FISH for the genetic analysis is probably harmful. The currently available evidence is insufficient to support PGT-A in routine clinical practice.

The prevalence, promotion and pricing of three IVF add-ons on fertility clinic websites

RESEARCH QUESTION

How are IVF clinic websites advertising three common IVF add-ons: assisted hatching, time-lapse embryo imaging and preimplantation genetic testing for aneuploidies (PGT-A)?

DESIGN

The Human Fertilisation and Embryology Authority 'Choose a fertility clinic' website service was used to identify IVF clinics and their websites. Assisted hatching, time-lapse embryo imaging and PGT-A were examined to determine which websites advertised them, what price they charged and what claims they made in relation to the add-ons.

RESULTS

Eighty-seven eligible clinics were identified, with 72 unique websites; 37 (43%) clinics were part of one of nine groups of IVF clinics, of sizes ranging from two to eight clinics in the UK. Time-lapse imaging (TLI) was the most frequently advertised of the three add-ons (67% of clinics), followed by PGT-A (47%) and assisted hatching (28%). Very few websites stated that the effectiveness of the add-on was in doubt or unclear (four, two and one websites for TLI, PGT-A and assisted hatching, respectively), and none raised the possibility that an add-on might have negative effects. Claims of efficacy were often based on upstream outcomes (e.g. implantation, pregnancy). Some claims that PGT-A and TLI improved live birth rates were found. There was substantial variation in pricing.

CONCLUSIONS

IVF clinic websites provide valuable information for patients seeking fertility treatment so it is key that the information is accurate and complete. There is a need for transparent information on interventions, including uncertainties and risks, to be made available by IVF clinics to support well-informed treatment decisions. The selected add-ons are widely advertised, and there is wide variation in pricing.

Predicting The Developmental Potential Of Cleavage Stage Embryos Based On Oxygen Consumption Rate In FET Cycles

OBJECTIVE

To study the value of oxygen consumption (OC) as a predictor of the developmental potential of D3 embryos in frozen embryo transfer (FET) cycles.

METHODS

This observational study included 148 patients undergoing FET cycles with two embryos transferred per cycle. OC rates were examined by scanning electrochemical microscopy before embryo transfer. Implantation, clinical pregnancy, miscarriage, and live birth rates were calculated.

RESULTS

A total of 296 embryos were transferred in 148 cycles, or two embryos per cycle. The embryos were divided into three groups based on OC: Group A included the cases in which the OC rate of each of the two transferred embryos was greater than 3.0 fmol/s; Group B included the cases in which the OC rate of one of the embryos was greater than 3.0 fmol/s and the OC rate of the other embryo was less than 3.0 fmol/s; and Group C included the cases in which the OC rates of the two embryos were less than 3.0 fmol/s. Higher live birth rates and lower miscarriage rates were observed in Group A (p<0.05).

CONCLUSIONS

Our data suggest that OC is positively correlated with embryo developmental potential. Therefore, measuring the OC of human embryos may be useful in embryo assessment.

A Preclinical Evaluation towards the Clinical Application of Oxygen Consumption Measurement by CERMs by a Mouse Chimera Model

We have developed an automated device for the measurement of oxygen consumption rate (OCR) called Chip-sensing Embryo Respiratory Measurement system (CERMs). To verify the safety and the significance of the OCR measurement by CERMs, we conducted comprehensive tests using a mouse model prior to clinical trials in a human in vitro fertilization (IVF) program. Embryo transfer revealed that the OCR measured by CERMs did not compromise the full-term development of mice or their future fertility, and was positively correlated with adenosine triphosphate (ATP) production and the mitochondrial membrane potential (ΔΨm), thereby indirectly reflecting mitochondrial oxidative phosphorylation (OXPHOS) activity. We demonstrated that the OCR is independent of embryo morphology (the size) and number of mitochondria (mitochondrial DNA copy number). The OCR correlated with the total cell numbers, whereas the inner cell mass (ICM) cell numbers and the fetal developmental rate were not. Thus, the OCR may serve as an indicator of the numbers of trophectoderm (TE) cells, rather than number or quality of ICM cells. However, implantation ability was neither correlated with the OCR, nor the embryo size in this model. This can probably be attributed to the limitation that chimeric embryos contain non-physiological high TE cells counts that are beneficial for implantation. CERMs can be safely employed in clinical IVF owing to it being a safe, highly effective, non-invasive, accurate, and quantitative tool for OCR measurement. Utilization of CERMs for clinical testing of human embryos would provide further insights into the nature of oxidative metabolism and embryonic viability.

Can trophectoderm RNA analysis predict human blastocyst competency?

A systematic review of the literature showed that trophectoderm biopsy could assist in the selection of healthy embryos for uterine transfer without affecting implantation rates. However, previous studies attempting to establish the relationship between trophectoderm gene expression profiles and implantation competency using either microarrays or RNA sequencing strategies, were not sufficiently optimized to handle the exceptionally low RNA inputs available from biopsied material. In this pilot study, we report that differential gene expression in human trophectoderm biopsies assayed by an ultra-sensitive next generation RNA sequencing strategy could predict blastocyst implantation competence. RNA expression profiles from isolated human trophectoderm cells were analysed with established clinical pregnancy being the primary endpoint. Following RNA sequencing, a total of 47 transcripts were found to be significantly differentially expressed between the trophectoderm cells from successfully implanted (competent) versus unsuccessful (incompetent) blastocysts. Of these, 36 transcripts were significantly down-regulated in the incompetent blastocysts, including Hydroxysteroid 17-Beta Dehydrogenase 1 (HSD17B1) and Cytochrome P450 Family 11 Subfamily A Member 1 (CYP11A1), while the remaining 11 transcripts were significantly up-regulated, including BCL2 Antagonist/Killer 1 (BAK1) and KH Domain Containing 1 Pseudogene 1 (KHDC1P1) of which the latter was always detected in the incompetent and absent in all competent blastocysts. Ontological analysis of differentially expressed RNAs revealed pathways involved in steroidogenic processes with high confidence. Novel differentially expressed transcripts were also noted by reference to a de novo sequence assembly. The selection of the blastocyst with the best potential to support full-term pregnancy following single embryo transfer could reduce the need for multiple treatment cycles and embryo transfers. The main limitation was the low sample size (N = 8). Despite this shortcoming, the pilot suggests that trophectoderm biopsy could assist with the selection of healthy embryos for embryo transfer. A larger cohort of samples is needed to confirm these findings. Abbreviations: AMA: advanced maternal age; ART: assisted reproductive technology; CP: clinical pregnancy; DE: differential expression; FDR: false discovery rate; IVF: in vitro fertilization; LD PCR: long distance PCR; qRT-PCR: quantitative real-time PCR; SET: single embryo transfer; TE: trophectoderm.

Use of Cumulative Live Birth Rate per Total Number of Embryos to Calculate the Success of IVF in Consecutive IVF Cycles in Women Aged ≥35 Years

Objective

The use of cumulative live birth rate (CLBR) per ovarian stimulation cycle is proving to be an accurate method to calculate the success of IVF; however, the cycle outcome is closely associated with the number of embryos transferred (ET). Our aim was to report CLBR after IVF according to the number of embryos required to achieve a live birth in women aged ≥35 years, considering age, body mass index (BMI), and ethnicity.

Methods

We conducted a retrospective cohort study including 1344 patients who underwent IVF between January 2013 and June 2016 at the First Affiliated Hospital of Xinjiang Medical University. The cumulative probability of live birth for each couple was estimated using the Kaplan–Meier method, and survival curves were compared according to age, BMI, and ethnicity using the log-rank test.

Results

CLBR increased rapidly from 1 to 5 ETs, moderately from 6 to 10 ETs, and slowly thereafter. CLBR was significantly different across 4 categories based on BMI as well as across those based on age; low CLBR was significantly associated with the age of ≥42 years and obesity.

Conclusion

The association between CLBR and number of ET provides realistic and precise information regarding the success of IVF and can be applied to guide clinicians and patients.

Assisted reproductive technology: an overview of Cochrane Reviews

BACKGROUND

As many as one in six couples will encounter problems with fertility, defined as failure to achieve a clinical pregnancy after regular intercourse for 12 months. Increasingly, couples are turning to assisted reproductive technology (ART) for help with conceiving and ultimately giving birth to a healthy live baby of their own. Fertility treatments are complex, and each ART cycle consists of several steps. If one of these steps is incorrectly applied, the stakes are high as conception may not occur. With this in mind, it is important that each step of the ART cycle is supported by good evidence from well-designed studies.

OBJECTIVES

To summarise the evidence from Cochrane systematic reviews on procedures and treatment options available to couples with subfertility undergoing assisted reproductive technology (ART) procedures.

METHODS

Published Cochrane systematic reviews of couples undergoing ART procedures (in vitro fertilisation or intracytoplasmic sperm injection) were eligible for inclusion in the overview. We also identified Cochrane reviews in preparation, for future inclusion.The primary outcome of the overview was live birth or the composite outcome live birth or ongoing pregnancy, as reported by the included reviews. Our secondary outcomes were clinical pregnancy, multiple pregnancy, miscarriage, and ovarian hyperstimulation syndrome. We excluded studies of intrauterine insemination and ovulation induction.We undertook selection of systematic reviews, data extraction, and quality assessment in duplicate. We assessed review quality by using the AMSTAR tool. We organised reviews by their relevance to specific stages in the ART cycle. We summarised their findings in the text and reported data for each outcome in 'Additional tables'.

MAIN RESULTS

We included 68 systematic reviews published in the Cochrane Library up to May 2018. All were of high quality. These reviews identified 38 interventions that were effective (n = 23) or promising (n = 15), and they identified 19 interventions that were ineffective (n = 2) or possibly ineffective (n = 17). For 15 interventions, review authors were unable to draw conclusions owing to lack of evidence.We identified an additional 11 protocols and four titles for future inclusion in this overview.

AUTHORS' CONCLUSIONS

This overview provides the most up-to-date evidence on ART cycles from systematic reviews of randomised controlled trials. Fertility treatments are costly, and the stakes are high. Using the best available evidence to optimise outcomes is best practice. Evidence from this overview could be used to develop clinical practice guidelines and protocols that can be applied in daily clinical practice to improve live birth rates and reduce rates of multiple pregnancy, cycle cancellation, and ovarian hyperstimulation syndrome.

Acquisition of oocyte competence to develop as an embryo: integrated nuclear and cytoplasmic events

Infertility affects ~7% of couples of reproductive age with little change in incidence in the last two decades. ART, as well as other interventions, have made major strides in correcting this condition. However, and in spite of advancements in the field, the age of the female partner remains a main factor for a successful outcome. A better understanding of the final stages of gamete maturation yielding an egg that can sustain embryo development and a pregnancy to term remains a major area for improvement in the field. This review will summarize the major cellular and molecular events unfolding at the oocyte-to-embryo transition. We will provide an update on the most important processes/pathways currently understood as the basis of developmental competence, including the molecular processes involved in mRNA storage, its recruitment to the translational machinery, and its degradation. We will discuss the hypothesis that the translational programme of maternal mRNAs plays a key role in establishing developmental competence. These regulations are essential to assemble the machinery that is used to establish a totipotent zygote. This hypothesis further supports the view that embryogenesis begins during oogenesis. A better understanding of the events required for developmental competence will guide the development of novel strategies to monitor and improve the success rate of IVF. Using this information, it will be possible to develop new biomarkers that may be used to better predict oocyte quality and in selection of the best egg for IVF.

One thousand seventy-eight autologous IVF cycles in women 45 years and older: the largest single-center cohort to date

PURPOSE

The purpose of this study was to determine IVF outcomes in women 45 years and older using autologous oocytes.

METHODS

This is a retrospective cohort study reviewing all IVF cycles in women ≥ 45 years old from January 1995 to June 2015 that were conducted at one academic medical center. One thousand seventy-eight fresh, autologous IVF cycles met inclusion criteria. PGD/S, natural IVF, and donor egg cycles were excluded. Outcomes were analyzed for the different age groups (age 45, n = 773; age 46, n = 221; age 47, n = 57; age 48, n = 22; age 49, n = 5). Primary outcome measures included IVF cycle characteristics, total pregnancy loss, clinical pregnancy, and live birth rates, and were stratified according to patient age.

RESULTS

Mean age of patients in the study cohort was 45.4 ± 0.72. 11.7% of patients did not start due to an elevated FSH or cyst and 28.5% of patients were canceled prior to oocyte retrieval. The overall pregnancy rate per transfer was 18.7% (117/626), of which 82.1% ended in a pregnancy loss. The overall clinical pregnancy and live birth rates per transfer were 9.6 and 3.4%, respectively, which did not differ between age groups. Per cycle start women aged 45 had significantly higher positive pregnancy rates compared to women aged 46 and 47 (14.1 vs. 8.6 vs. 5.9%, p = 0.04). For women 45 years old, the live birth rate was 2.9% per cycle start and was 4.4% per embryo transfer. Of the 21 live births, 20 were in women aged 45 and one live birth was in a 46-year-old woman. There were no live births in any patient with ≤ 4 oocytes retrieved.

CONCLUSION

Autologous IVF in women aged 45 with acceptable ovarian reserve is not futile; however, it does carry very low prognosis. Patients aged 46 and older should be counseled appropriately that a live birth seems highly unlikely.

A single trophectoderm biopsy at blastocyst stage is mathematically unable to determine embryo ploidy accurately enough for clinical use

BACKGROUND

It has become increasingly apparent that the trophectoderm (TE) at blastocyst stage is much more mosaic than has been appreciated. Whether preimplantation genetic screening (PGS), utilizing a single TE biopsy (TEB), can reliably determine embryo ploidy has, therefore, increasingly been questioned in parallel.

METHODS

We for that reason here established 2 mathematical models to assess probabilities of false-negative and false-positive results of an on average 6-cell biopsy from an approximately 300-cell TE. This study was a collaborative effort between investigators at The Center for Human Reproduction in New York City and the Center for Studies in Physics and Biology and the Brivanlou Laboratory of Stem Cell Biology and Molecular Embryology, the latter two both at Rockefeller University in New York City.

RESULTS

Both models revealed that even under best case scenario, assuming even distribution of mosaicism in TE (since mosaicism is usually clonal, a highly unlikely scenario), a biopsy of at least 27 TE cells would be required to reach minimal diagnostic predictability from a single TEB.

CONCLUSIONS

As currently performed, a single TEB is, therefore, mathematically incapable of reliably determining whether an embryo can be transferred or should be discarded. Since a single TEB, as currently performed, apparently is not representative of the complete TE, this study, thus, raises additional concern about the clinical utilization of PGS.

Interventions for the prevention of OHSS in ART cycles: an overview of Cochrane reviews

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) in assisted reproductive technology (ART) cycles is a treatment-induced disease that has an estimated prevalence of 20% to 33% in its mild form and 3% to 8% in its moderate or severe form. These numbers might even be higher for high-risk women such as those with polycystic ovaries or a high oocyte yield from ovum pickup.

OBJECTIVES

The objective of this overview is to identify and summarise all evidence from Cochrane systematic reviews on interventions for prevention or treatment of moderate, severe and overall OHSS in couples with subfertility who are undergoing ART cycles.

METHODS

Published Cochrane systematic reviews reporting on moderate, severe or overall OHSS as an outcome in ART cycles were eligible for inclusion in this overview. We also identified Cochrane submitted protocols and title registrations for future inclusion in the overview. The evidence is current to 12 December 2016. We identified reviews, protocols and titles by searching the Cochrane Gynaecology and Fertility Group Database of Systematic Reviews and Archie (the Cochrane information management system) in July 2016 on the effectiveness of interventions for outcomes of moderate, severe and overall OHSS. We undertook in duplicate selection of systematic reviews, data extraction and quality assessment. We used the AMSTAR (Assessing the Methodological Quality of Systematic Reviews) tool to assess the quality of included reviews, and we used GRADE methods to assess the quality of the evidence for each outcome. We summarised the characteristics of included reviews in the text and in additional tables.

MAIN RESULTS

We included a total of 27 reviews in this overview. The reviews were generally of high quality according to AMSTAR ratings, and included studies provided evidence that ranged from very low to high in quality. Ten reviews had not been updated in the past three years. Seven reviews described interventions that provided a beneficial effect in reducing OHSS rates, and we categorised one additional review as 'promising'. Of the effective interventions, all except one had no detrimental effect on pregnancy outcomes. Evidence of at least moderate quality indicates that clinicians should consider the following interventions in ART cycles to reduce OHSS rates.• Metformin treatment before and during an ART cycle for women with PCOS (moderate-quality evidence).• Gonadotrophin-releasing hormone (GnRH) antagonist protocol in ART cycles (moderate-quality evidence).• GnRH agonist (GnRHa) trigger in donor oocyte or 'freeze-all' programmes (moderate-quality evidence). Evidence of low or very low quality suggests that clinicians should consider the following interventions in ART cycles to reduce OHSS rates.• Clomiphene citrate for controlled ovarian stimulation in ART cycles (low-quality evidence).• Cabergoline around the time of human chorionic gonadotrophin (hCG) administration or oocyte pickup in ART cycles (low-quality evidence).• Intravenous fluids (plasma expanders) around the time of hCG administration or oocyte pickup in ART cycles (very low-quality evidence).• Progesterone for luteal phase support in ART cycles (low-quality evidence).• Coasting (withholding gonadotrophins) - a promising intervention that needs to be researched further for reduction of OHSS.On the basis of this overview, we must conclude that evidence is currently insufficient to support the widespread practice of embryo cryopreservation.

AUTHORS' CONCLUSIONS

Currently, 27 reviews in the Cochrane Library were conducted to report on or to try to report on OHSS in ART cycles. We identified four review protocols but no new registered titles that can potentially be included in this overview in the future. This overview provides the most up-to-date evidence on prevention of OHSS in ART cycles from all currently published Cochrane reviews on ART. Clinicians can use the evidence summarised in this overview to choose the best treatment regimen for individual patients - a regimen that not only reduces the chance of developing OHSS but does not compromise other outcomes such as pregnancy or live birth rate. Review results, however, are limited by the lack of recent primary studies or updated reviews. Furthermore, this overview can be used by policymakers in developing local and regional protocols or guidelines and can reveal knowledge gaps for future research.

Age as A Predictor of Embryo Quality Regardless of The Quantitative Ovarian Response

Background

One determining factor of a successful in vitro fertilization (IVF) cycle is embryo quality. The aim of the present study was to evaluate associations of embryo quality and reserve markers like age, FSH and AMH.

Materials and Methods

In this prospective study, 120 infertile women, aged 21-44 years, undergoing routine exploration during an unstimulated cycle preceding assisted reproductive technology (ART) at our center were studied prospectively, from February 2011 to December 2014. Descriptive parameters and patient characteristics were reported as mean (SD) or median (range) depending on the distribution. Student’s t test was performed for continuous variables, Wilcoxon and Pearson’s Test were used for not distributed variables and Fisher’s Test was performed for categorical variables. P<0.05 was considered statistically significant.

Results

Overall, at the time of investigation, patients had a mean age of 33.03 ± 4.15 years old. On cycle day three, serum anti-Mullerian hormone (AMH) level was 3.50 ± 1.54 ng/mL, serum follicle-stimulating hormone (FSH) level was 6.29 ± 1.53 mUI/ mL, at baseline, women had 16.57 ± 7.0 antral follicles. The mean of collected oocytes was 11.80 ± 5.25, embryo I+II was 2.46 ± 2.11. A greater number of embryos I+II was observed in young patients. By evaluating 120 patients, a significant relationship was observed between age and FSH (r=0.24, P=0.01), age with AMH (r=-0.22, P=0.02), age with collected oocytes (r=-0.23, P=0.03) and age with embryo I+II (r=-0.22, P=0.03). A significant relationship was also observed between antral follicle count (AFC) and AMH (r=0.29, P=0.01), AFC and the number of transferred embryo (r=-0.18, P=0.03), AFC and total dose of the drugs (r=-0.23, P=0.03). Significant relationship of FSH with total dose of drugs (r=0.19, P=0.02) was also observed. In addition, we determined significant relationships between AMH and the number of collected oocytes (r=0.38, P=0.01), AMH and the number of metaphase II oocytes (r= 0.35, P=0.01), AMH and the number of embryo (r=0.19, P=0.04) as well as AMH and total dose of the drugs (r=-0.25, P=0.01).

Conclusion

Commonly used clinical markers of ovarian reserve are reflection of the ovarian reserve, while the outcome measurements of ART and age are the best predictors of embryo quality.

Development of a new clinically applicable device for embryo evaluation which measures embryo oxygen consumption

STUDY QUESTION

Does a new system-the chip-sensing embryo respiration monitoring system (CERMs)-enable evaluation of embryo viability for potential application in a clinical IVF setting?

SUMMARY ANSWER

The system enabled the oxygen consumption rate of spheroids, bovine embryos and frozen-thawed human embryos to be measured, and this rate corresponded to the developmental potential of embryos.

WHAT IS ALREADY KNOWN

To date, no reliable and clinically suitable objective evaluation methods for embryos are available, which circumvent the differences in inter-observer subjective view. Existing systems such as the scanning electrochemical microscopy (SECM) technique, which enables the measurement of oxygen consumption rate in embryos, need improvement in usability before they can be applied to a clinical setting.

STUDY DESIGN, SIZE, DURATION

This is a prospective original research study. The feasibility of measuring the oxygen consumption rate was assessed using CERMs for 9 spheroids, 9 bovine embryos and 30 redundant frozen-thawed human embryos. The endpoints for the study were whether CERMs could detect a dissolved oxygen gradient with high sensitivity, had comparable accuracy to the SECM measuring system with improved usability, and could predict the development of an embryo to a blastocyst by measuring the oxygen consumption rate. The relationship between the oxygen consumption rate and standard morphological evaluation was also examined.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We developed a new CERMs, which enables the oxygen consumption rate to be measured automatically using an electrochemical method. The device was initially used for measuring a dissolved oxygen concentration gradient in order to calculate oxygen consumption rate using nine spheroids. Next, we evaluated data correlation between the CERMs and the SECM measuring systems using nine bovine embryos. Finally, the oxygen consumption rates of 30 human embryos, which were frozen-thawed on 2nd day after fertilization, were measured by CERMs at 6, 24, 48, 72 and 96 h after thawing with standard morphological evaluation. Furthermore, the developed blastocysts were scored using the blastocyst quality score (BQS), and the correlation with oxygen consumption rate was also assessed.

MAIN RESULTS AND THE ROLE OF CHANCE

The device enabled the oxygen consumption rate of an embryo to be measured automatically within a minute. The oxygen concentration gradient profile showed excellent linearity in a distance-dependent change. A close correlation in the oxygen consumption rates of bovine embryos was observed between the SECM measuring system and CERMs, with a determination coefficient of 0.8203 (P = 0.0008). Oxygen consumption rates of human embryos that have reached the blastocyst stage were significantly higher than those of arrested embryos at 48, 72 and 96 h after thawing (P = 0.039, 0.004 and 0.049, respectively). Thus, in vitro development of frozen-thawed human embryos to the blastocyst stage would be predicted at 48 h after thawing (day 4) by measuring the oxygen consumption using CERMs. Although a positive linear relationship between BQS and the oxygen consumption rate was observed [the determination coefficient was R(2) = 0.6537 (P = 0.008)], two blastocysts exhibited low oxygen consumption rates considering their relatively high BQS. This suggests that morphology and metabolism in human embryos might not correlate consistently.

LIMITATIONS, REASONS FOR CAUTION

Transfer of the embryo and pregnancy evaluation was not performed. Thus, a correlation between oxygen consumption and the in vivo viability of embryos remains unknown. Clinical trials, including embryo transfer, would be desirable to determine a threshold value to elect clinically relevant, quality embryos for transfer. We utilized frozen-thawed human embryos in this study. The effect of these manipulations on the respiratory activity of the embryo is also unknown.

WIDER IMPLICATIONS OF THE FINDINGS

Selection of quality embryos, especially in a single embryo transfer cycle, by CERMs may have an impact on obtaining better clinical outcomes, albeit with clinical trials being required. Furthermore, the early determination of quality embryos by CERMs may enable the omission of long-term in vitro embryo culture to the blastocyst stage. CERMs is scalable technology that can be integrated into incubators and/or other embryo evaluation systems, such as the time-lapse systems, due to its chip-based architecture. Thus, CERMS would enable automatic measurement of oxygen consumption, under 5% CO2, in the near future, in order to reduce oxidative stress from exposure to atmospheric air.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by grants from the Health and Labor Sciences Research Grant (H24-Hisaichiiki-Shitei-016). The authors have no conflicts of interest.

TRIAL REGISTRATION NUMBER

Not applicable.

Anti-Müllerian hormone levels as a predictor of clinical pregnancy in in vitro fertilization/intracytoplasmic sperm injection-embryo transfer cycles in patients over 40 years of age

Objective

The aim of the current study was to determine the predictive value of anti-Müllerian hormone (AMH) levels for pregnancy outcomes in patients over 40 years of age who underwent in vitro fertilization or intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) cycles.

Methods

We retrospectively analyzed the medical records of 188 women aged 40 to 44 years who underwent IVF/ICSI-fresh ET cycles due to unexplained infertility in the fertility center of CHA Gangnam Medical Center. Patients were divided into group A, with AMH levels <1.0 ng/mL (n=97), and group B, with AMH levels ≥1.0 ng/mL (n=91). We compared the clinical pregnancy rate (CPR) in the two groups and performed logistic regression analysis to identify factors that had a significant effect on the CPR.

Results

The CPR was significantly lower in group A than group B (7.2% vs. 24.2%, p<0.001). In multivariate logistic regression analysis, AMH levels were the only factor that had a significant impact on the CPR (odds ratio, 1.510; 95% confidence interval, 1.172-1.947). The area under the receiver operating characteristic curve for AMH levels as a predictor of the CPR was 0.721. When the cut-off level of AMH was set at 1.90 ng/mL, the CPR was 6.731-fold higher in the group with AMH levels ≥1.90 ng/mL than in the group with AMH levels <1.90 ng/mL (p<0.001).

Conclusion

Our study showed that AMH levels were predictive of clinical pregnancy in infertility patients over 40 years of age. Further prospective studies should be conducted to validate the predictive capability of AMH levels for the outcome of clinical pregnancy.

Add-ons in IVF programme - Hype or Hope?

A series of new technologies and adjuvant therapies have been advocated in order to improve the success of IVF treatment. Dehydro-epiandrostenedione, growth hormones, Coenzyme Q 10, calcium ionosphores, immune therapy, heparin, low-dose aspirin, and vasodilators are among commonly prescribed pharmacological adjuvants. New technologies that are proposed to improve IVF outcomes include advanced sperm selection procedures, time- lapse embryo monitoring, preimplantation genetic screening, assisted hatching endometrial injury or embryo-glue. This review looked into current evidence to justify the use of these co-interventions and whether some of them can still be offered while awaiting more robust evidence to con rm or refute their role.

Assisted reproductive technology: an overview of Cochrane Reviews

BACKGROUND

As many as one in six couples will encounter problems with fertility, defined as failure to achieve a clinical pregnancy after regular intercourse for 12 months. Increasingly, couples are turning to assisted reproductive technology (ART) for help with conceiving and ultimately giving birth to a healthy live baby of their own. Fertility treatments are complex, and each ART cycle consists of several steps. If one of the steps is incorrectly applied, the stakes are high as conception may not occur. With this in mind, it is important that each step of the ART cycle is supported by good evidence from well-designed studies.

OBJECTIVES

To summarise the evidence from Cochrane systematic reviews on procedures and treatment options available to couples with subfertility undergoing assisted reproductive technology (ART).

METHODS

Published Cochrane systematic reviews of couples undergoing ART (in vitro fertilisation or intracytoplasmic sperm injection) were eligible for inclusion in the overview. We also identified Cochrane reviews in preparation, for future inclusion.The outcomes of the overview were live birth (primary outcome), clinical pregnancy, multiple pregnancy, miscarriage and ovarian hyperstimulation syndrome (secondary outcomes). Studies of intrauterine insemination and ovulation induction were excluded.Selection of systematic reviews, data extraction and quality assessment were undertaken in duplicate. Review quality was assessed by using the AMSTAR tool. Reviews were organised by their relevance to specific stages in the ART cycle. Their findings were summarised in the text and data for each outcome were reported in 'Additional tables'.

MAIN RESULTS

Fifty-nine systematic reviews published in The Cochrane Library up to July 2015 were included. All were high quality. Thirty-two reviews identified interventions that were effective (n = 19) or promising (n = 13), 14 reviews identified interventions that were either ineffective (n = 2) or possibly ineffective (n = 12), and 13 reviews were unable to draw conclusions due to lack of evidence.An additional 11 protocols and five titles were identified for future inclusion in this overview.

AUTHORS' CONCLUSIONS

This overview provides the most up to date evidence on ART cycles from systematic reviews of randomised controlled trials. Fertility treatments are costly and the stakes are high. Using the best available evidence to optimise outcomes is best practice. The evidence from this overview could be used to develop clinical practice guidelines and protocols for use in daily clinical practice, in order to improve live birth rates and reduce rates of multiple pregnancy, cycle cancellation and ovarian hyperstimulation syndrome.

Increasing live birth rate by preimplantation genetic screening of pooled polar bodies using array comparative genomic hybridization

Meiotic errors during oocyte maturation are considered the major contributors to embryonic aneuploidy and failures in human IVF treatment. Various technologies have been developed to screen polar bodies, blastomeres and trophectoderm cells for chromosomal aberrations. Array-CGH analysis using bacterial artificial chromosome (BAC) arrays is widely applied for preimplantation genetic diagnosis (PGD) using single cells. Recently, an increase in the pregnancy rate has been demonstrated using array-CGH to evaluate trophectoderm cells. However, in some countries, the analysis of embryonic cells is restricted by law. Therefore, we used BAC array-CGH to assess the impact of polar body analysis on the live birth rate. A disadvantage of polar body aneuploidy screening is the necessity of the analysis of both the first and second polar bodies, resulting in increases in costs for the patient and complex data interpretation. Aneuploidy screening results may sometimes be ambiguous if the first and second polar bodies show reciprocal chromosomal aberrations. To overcome this disadvantage, we tested a strategy involving the pooling of DNA from both polar bodies before DNA amplification. We retrospectively studied 351 patients, of whom 111 underwent polar body array-CGH before embryo transfer. In the group receiving pooled polar body array-CGH (aCGH) analysis, 110 embryos were transferred, and 29 babies were born, corresponding to live birth rates of 26.4% per embryo and 35.7% per patient. In contrast, in the control group, the IVF treatment was performed without preimplantation genetic screening (PGS). For this group, 403 embryos were transferred, and 60 babies were born, resulting in live birth rates of 14.9% per embryo and 22.7% per patient. In conclusion, our data show that in the aCGH group, the use of aneuploidy screening resulted in a significantly higher live birth rate compared with the control group, supporting the benefit of PGS for IVF couples in addition to the suitability and effectiveness of our polar body pooling strategy.

Assisted reproductive technology: an overview of Cochrane reviews

BACKGROUND

As many as one in six couples will encounter problems with fertility, defined as failure to achieve a clinical pregnancy after regular intercourse for 12 months. Increasingly, couples are turning to assisted reproductive technology (ART) for help with conceiving and ultimately giving birth to a healthy live baby of their own. Fertility treatments are complex, and each ART cycle consists of several steps. If one of the steps is incorrectly applied, the stakes are high as conception may not occur. With this in mind, it is important that each step of the ART cycle is supported by good evidence from well-designed studies.

OBJECTIVES

To summarise the evidence from Cochrane systematic reviews on procedures and treatment options available to couples with subfertility undergoing assisted reproductive technology (ART).

METHODS

Published Cochrane systematic reviews of couples undergoing ART (in vitro fertilisation or intracytoplasmic sperm injection) were eligible for inclusion in the overview. We also identified Cochrane reviews in preparation, for future inclusion.The outcomes of the overview were live birth (primary outcome), clinical pregnancy, multiple pregnancy, miscarriage and ovarian hyperstimulation syndrome (secondary outcomes). Studies of intrauterine insemination and ovulation induction were excluded.Selection of systematic reviews, data extraction and quality assessment were undertaken in duplicate. Review quality was assessed by using the AMSTAR tool. Reviews were organised by their relevance to specific stages in the ART cycle. Their findings were summarised in the text and data for each outcome were reported in 'Additional tables'.

MAIN RESULTS

Fifty-eight systematic reviews published in The Cochrane Library were included. All were high quality. Thirty-two reviews identified interventions that were effective (n = 19) or promising (n = 13), 14 reviews identified interventions that were either ineffective (n = 3) or possibly ineffective (n=11), and 12 reviews were unable to draw conclusions due to lack of evidence.An additional 11 protocols and one title were identified for future inclusion in this overview.

AUTHORS' CONCLUSIONS

This overview provides the most up to date evidence on ART cycles from systematic reviews of randomised controlled trials. Fertility treatments are costly and the stakes are high. Using the best available evidence to optimise outcomes is best practice. The evidence from this overview could be used to develop clinical practice guidelines and protocols for use in daily clinical practice, in order to improve live birth rates and reduce rates of multiple pregnancy, cycle cancellation and ovarian hyperstimulation syndrome.

Preimplantation genetic diagnosis for monogenic diseases: overview and emerging issues

Preimplantation genetic diagnosis (PGD) is an established reproductive option for couples at risk of conceiving a pregnancy affected with a known genetic disease, who wish to avoid an (additional) affected child, termination of pregnancy or recurrent miscarriages. Early technologies concentrated on different approaches to direct mutation testing for monogenic diseases using single cell PCR protocols, or sex selection by fluorescent in situ hybridization for X-linked monogenic disease. Development of multiplex fluorescent PCR allowed simultaneously testing of linked markers alongside the mutation test, increasing the accuracy by controlling for contamination and identifying allele drop-out. The advent of highly effective whole genome amplification methods has opened the way for new technologies such as preimplantation genetic haplotyping and microarrays, thus increasing the number of genetic defects that can be detected in preimplantation embryos; the number of cases carried out and the new indications tested increases each year. Different countries have taken very different approaches to legislating and regulating PGD, giving rise to the phenomenon of reproductive tourism. PGD is now being performed for scenarios previously not undertaken using prenatal diagnosis, some of which raise significant ethical concerns. While PGD has benefited many couples aiming to have healthy children, ethical concerns remain over inappropriate use of this technology.

Assisted reproductive technology: an overview of Cochrane Reviews

BACKGROUND

As many as one in six couples will encounter problems with fertility, defined as failure to achieve a clinical pregnancy after regular intercourse for 12 months. Increasingly, couples are turning to assisted reproductive technology (ART) for help with conceiving and ultimately giving birth to a healthy live baby of their own. Fertility treatments are complex, and each ART cycle consists of several steps. If one of the steps is incorrectly applied, the stakes are high as conception may not occur. With this in mind, it is important that each step of the ART cycle is supported by good evidence from well-designed studies.

OBJECTIVES

To summarise the evidence from Cochrane systematic reviews on procedures and treatment options available to couples with subfertility undergoing assisted reproductive technology (ART).

METHODS

Published Cochrane systematic reviews of couples undergoing ART (in vitro fertilisation or intracytoplasmic sperm injection) were eligible for inclusion in the overview. We also identified Cochrane reviews in preparation, for future inclusion.The outcomes of the overview were live birth (primary outcome), clinical pregnancy, multiple pregnancy, miscarriage and ovarian hyperstimulation syndrome (secondary outcomes). Studies of intrauterine insemination and ovulation induction were excluded.Selection of systematic reviews, data extraction and quality assessment were undertaken in duplicate. Review quality was assessed by using the AMSTAR tool. Reviews were organised by their relevance to specific stages in the ART cycle. Their findings were summarised in the text and data for each outcome were reported in 'Additional tables'.

MAIN RESULTS

Fifty-four systematic reviews published in The Cochrane Library were included. All were high quality. Thirty reviews identified interventions that were effective (n = 18) or promising (n = 12), 13 reviews identified interventions that were either ineffective (n = 3) or possibly ineffective (n=10), and 11 reviews were unable to draw conclusions due to lack of evidence.An additional 15 protocols and two titles were identified for future inclusion in this overview.

AUTHORS' CONCLUSIONS

This overview provides the most up to date evidence on ART cycles from systematic reviews of randomised controlled trials. Fertility treatments are costly and the stakes are high. Using the best available evidence to optimise outcomes is best practice. The evidence from this overview could be used to develop clinical practice guidelines and protocols for use in daily clinical practice, in order to improve live birth rates and reduce rates of multiple pregnancy, cycle cancellation and ovarian hyperstimulation syndrome.

A review of, and commentary on, the ongoing second clinical introduction of preimplantation genetic screening (PGS) to routine IVF practice

PURPOSE

Current re-introduction of "improved" preimplantation genetic screening (PGS#2) raises the question whether PGS#2 is ready for routine clinical application.

METHODS

We assessed available evidence via review of published data for years 2005-2012, and review of currently ongoing registered clinical trials, based on searches under appropriate key words in PubMed, MEDLINE, Cochrane Database System Review and Google Scholar and http://www.ClinicalTrials.gov . In absence of prospective clinical trials, and due to limited available data, individual publications/ongoing studies are assessed.

RESULTS

PGS#2 offers significant improvements in accuracy of aneuploidy diagnosis over PGS#1. By moving embryo biopsy from day-3 after fertilization (6-8 cell stage) to trophectoderm biopsy at blastocyst stage (day 5-6), PGS#2, however, adds additional co-variables to the analysis of efficacy of the procedure, which have special relevance for women with diminished ovarian reserve (DOR), who usually produce small egg and embryo numbers. Limited published data, claiming efficacy of PGS#2, as well as ongoing clinical trials, do not consider these additional co-variables, do not analyze outcomes by intent to treat and, therefore, have to be considered biased in patient selection.

CONCLUSIONS

Here reached conclusions are based on absence of adequate data rather than affirmative outcome assessments. They, therefore, are subject to change at any future date with generation of significant new data. Premature introduction of PGS#1 caused significant damage to patients. As currently no reliable PGS#2 data are available to suggest improvements in IVF outcomes, to avoid a repeat of the PGS#1 experience, PGS#2 should be considered experimental until data show otherwise.

Follicular fluid protein content (FSH, LH, PG4, E2 and AMH) and polar body aneuploidy

PURPOSE

Our objective was to identify a marker for oocyte aneuploidy in follicular fluid (FF) in women with an increased risk of oocyte aneuploidy after controlled ovarian hyperstimulation.

MATERIALS AND METHODS

Three groups of oocytes were constituted for polar body screening by FISH (chromosomes 13, 16, 18, 21 and 22): Group 1, advanced maternal age (n = 156); Group 2, implantation failure (i.e. no pregnancy after the transfer of more than 10 embryos; n = 101) and Group 3, implantation failure and advanced maternal age (n = 56). FSH and other proteins were assayed in the corresponding FF samples.

RESULTS

Of the 313 oocytes assessed, 35.78 % were abnormal. We found a significant difference between the follicular FSH levels in normal oocytes and abnormal oocytes (4.85 ± 1.75 IU/L vs. 5.41 ± 2.47 IU/L, respectively; p = 0.021). We found that the greater the number of chromosomal abnormalities per oocyte (between 0 and 3), the higher the follicular FSH level.

CONCLUSION

High FF FSH levels were associated with oocyte aneuploidy in women having undergone controlled ovarian hyperstimulation.

Atosiban improves implantation and pregnancy rates in patients with repeated implantation failure

This prospective cohort study examined the effects of atosiban on uterine contraction, implantation rate (IR) and clinical pregnancy rate (CPR) in women undergoing IVF/embryo transfer. The study enrolled 71 women with repeated implantation failure (RIF; no pregnancies from an average of 4.8 previous embryo transfers with a mean of 12 top-quality embryos) undergoing IVF/embryo transfer using cryopreserved embryos. The total atosiban dose was 36.75 mg. The IR per transfer and CPR per cycle were 13.9% and 43.7%, respectively. Before atosiban, 14% of subjects had a high frequency of uterine contractions (≥ 16 in 4 min). The frequency of uterine contractions was reduced after atosiban. This reduction of uterine contractions in all cycles was significant overall (from 6.0 to 2.6/4 min; P<0.01), in cycles with ≥ 16 uterine contractions/4 min at baseline (from 18.8 to 5.1; P<0.01) and in cycles with <16 uterine contractions/4 min (from 3.9 to 2.2; P<0.01). IR and CPR improved in all subjects, irrespective of baseline uterine contraction frequency. This is the first prospective study showing that atosiban may benefit subjects with RIF undergoing IVF/embryo transfer with cryopreserved embryos. One potential mechanism is the reduction in uterine contractility, but others may also contribute. Many women undergoing IVF/embryo transfer do not achieve the outcome that they wish for. In fact, IVF/embryo transfer repeatedly fails for a subgroup of patients. There are limited options available to help these patients with repeat implantation failure (RIF) to become pregnant. This study looks at one potential new treatment option for women who experience RIF. A drug called atosiban is already being used to delay premature labour by inhibiting contractions of the uterus. In this study, atosiban was given at the time of embryo transfer to women undergoing IVF/embryo transfer. Atosiban reduced the number of uterine contractions in these patients and also increased the implantation and pregnancy rates. The pregnancy rate went from zero to 43.7%. The beneficial effects of atosiban were observed not only in patients who had a high frequency of uterine contractions at baseline but also in those who had a low frequency. These findings suggest that atosiban may have other benefits in addition to its effect on contractions of the uterus. More studies are required to find out exactly how atosiban works and to increase the knowledge of its use in patients with RIF undergoing IVF/embryo transfer.

In vitro fertilization/intracytoplasmic sperm injection for male infertility

Progress in the field of assisted reproduction, and particularly micromanipulation, now heralds a new era in the management of severe male factor infertility, not amenable to medical or surgical correction. By overcoming natural barriers to conception, in vitro fertilization and embryo transfer (IVF-ET), subzonal sperm insemination, partial zona dissection, and intracytoplasmatic injection of sperm (ICSI) now offer couples considered irreversibly infertile, the option of parenting a genetically related child. However, unlike IVF, which necessitates an optimal sperm number and function to successfully complete the sequence of events leading to fertilization, micromanipulation techniques, such as ICSI, involving the direct injection of a spermatozoon into the oocyte, obviate all these requirements and may be used to alleviate severe male factor infertility due to the lack of sperm in the ejaculate due to severely impaired spermatogenesis (non-obstructive azoospermia) or non-reconstructable reproductive tract obstruction (obstructive azoospermia). ICSI may be performed with fresh or cryopreserved ejaculate sperm where available, microsurgically extracted epididymal or testicular sperm with satisfactory fertilization, clinical pregnancy, and ongoing pregnancy rates. However, despite a lack of consensus regarding the genetic implications of ICSI or the application and efficacy of preimplantation genetic diagnosis prior to assisted reproductive technology (ART), the widespread use of ICSI, increasing evidence of the involvement of genetic factors in male infertility and the potential risk of transmission of genetic disorders to the offspring, generate major concerns with regard to the safety of the technique, necessitating a thorough genetic evaluation of the couple, classification of infertility and adequate counseling of the implications and associated risks prior to embarking on the procedure. The objective of this review is to highlight the indications, advantages, limitations, outcomes, implications and safety of using IVF/ICSI for male factor infertility to enable a more judicious use of these techniques and maximize their potential benefits while minimizing foreseen complications.

In vitro fertilization (IVF): a review of 3 decades of clinical innovation and technological advancement

In vitro fertilization, popularly referred to as IVF, has captured the attention of the public since its sensational introduction in 1978. Today assisted reproductive technology is available throughout most of the civilized world, and the practice is largely different from that used during the early days. Refinements in laboratory technology and clinical practice have allowed IVF to evolve into a medical procedure that is efficient, safe, readily accessible, and relatively affordable. More than 2 million IVF children have been born to date, and it is likely that continued enhancements will widen its appeal and applicability.

Preimplantation genetic screening: does it help or hinder IVF treatment and what is the role of the embryo?

Despite an ongoing debate over its efficacy, preimplantation genetic screening (PGS) is increasingly being used to detect numerical chromosomal abnormalities in embryos to improve implantation rates after IVF. The main indications for the use of PGS in IVF treatments include advanced maternal age, repeated implantation failure, and recurrent pregnancy loss. The success of PGS is highly dependent on technical competence, embryo culture quality, and the presence of mosaicism in preimplantation embryos. Today, cleavage stage biopsy is the most commonly used method for screening preimplantation embryos for aneuploidy. However, blastocyst biopsy is rapidly becoming the more preferred method due to a decreased likelihood of mosaicism and an increase in the amount of DNA available for testing. Instead of using 9 to 12 chromosome FISH, a 24 chromosome detection by aCGH or SNP microarray will be used. Thus, it is advised that before attempting to perform PGS and expecting any benefit, extended embryo culture towards day 5/6 should be established and proven and the clinical staff should demonstrate competence with routine competency assessments. A properly designed randomized control trial is needed to test the potential benefits of these new developments.

Interventions in the prolongation of reproductive life in women

Women may seek to prolong their reproductive span for a variety of reasons. For many this implies reproduction at a late age, possibly driven by lifestyle decisions, but for others affected by a natural or a cancer treatment-induced premature ovarian failure it may simply mean seeking to achieve the normal reproductive span. The range of interventions now available to address the issue of prolonging reproductive life has never been greater, although several of the approaches discussed remain in the realm of future application through being dependent on ongoing scientific developments.

Dehydroepiandrosterone (DHEA) reduces embryo aneuploidy: direct evidence from preimplantation genetic screening (PGS)

BACKGROUND

Dehydroepiandrosterone (DHEA) has been reported to improve pregnancy chances in women with diminished ovarian reserve (DOR), and to reduce miscarriage rates by 50-80%. Such an effect is mathematically inconceivable without beneficial effects on embryo ploidy. This study, therefore, assesses effects of DHEA on embryo aneuploidy.

METHODS

In a 1:2, matched case control study 22 consecutive women with DOR, supplemented with DHEA, underwent preimplantation genetic screening (PGS) of embryos during in vitro fertilization (IVF) cycles. Each was matched by patient age and time period of IVF with two control IVF cycles without DHEA supplementation (n = 44). PGS was performed for chromosomes X, Y, 13, 16, 18, 21 and 22, and involved determination of numbers and percentages of aneuploid embryos.

RESULTS

DHEA supplementation to a significant degree reduced number (P = 0.029) and percentages (P < 0.001) of aneuploid embryos, adjusted for relevant covariates. Short term supplementation (4-12 weeks) resulted in greatest reduction in aneuploidy (21.6%, 95% CI -2.871-46.031).

DISCUSSION

Beneficial DHEA effects on DOR patients, at least partially, are the likely consequence of lower embryo aneuploidy. DHEA supplementation also deserves investigation in older fertile women, attempting to conceive, where a similar effect, potentially, could positively affect public health.

Analysis of pronuclear zygote configurations in 459 clinical pregnancies obtained with assisted reproductive technique procedures

BACKGROUND

Embryos selection is crucial to maintain high performance in terms of pregnancy rate, reducing the risk of multiple pregnancy during IVF. Pronuclear and nucleolar characteristics have been proposed as an indicator of embryo development and chromosomal complement in humans, providing information about embryo viability.

METHODS

To correlate the zygote-score with the maternal age and the outcome of pregnancy, we analyzed the pronuclear and nucleolar morphology, the polar body alignment and the zygote configuration in 459 clinical pregnancies obtained by IVF and ICSI in our public clinic in Reggio Emilia, Italy. We derived odds ratios (OR) and Corenfield's 95% confidence intervals (CI). Continuous variables were compared with Student's t-test; P lower than .05 was considered statistically significant.

RESULTS

We observed a significant increase of "A" pronuclear morphology configuration in 38-41 years old patients in comparison to that lower than or equal to 32 years old and a significant decrease of "B" configuration in 38-41 years old patients in comparison to that lower than or equal to 32 and in comparison to that of 33-37 years old. Related to maternal age we found no significant differences in P1 and in P2 configuration. We found no correlation between zygote-score, embryo cleavage and embryo quality.

CONCLUSIONS

Our results confirm the limited clinical significance of zygote-score suggesting that it can not be associated with maternal age, embryo cleavage and embryo quality. The evaluation of embryo quality based on morphological parameters is probably more predictive than zygote-score.

Slow and ultrarapid cryopreservation of biopsied mouse blastocysts and its effect on DNA integrity index

PURPOSE

To evaluate the effect of slow and ultra-rapid freezing on biopsied blastocysts' DNA integrity.

METHODS

Forty eight mouse blastocysts were biopsied of which 16 were cryopreserved by slowly freezing and 17 by vitrification. Fourteen intact blastocysts were slowly cryopreserved and 24 were vitrified. Eighteen fresh intact blastocysts and fifteen biopsied blastocysts served as controls. The DNA integrity index of all blastocysts was evaluated using (TUNEL) staining and confocal imaging

RESULTS

Both slow freezing and vitrification of biopsied blastocysts induced apoptosis to a similar extent. Biopsying blastocysts before vitrification resulted in less apoptosis than vitrification of intact blastocysts.

CONCLUSION

Slow freezing and vitrification are equal options for preservation of biopsied blastocysts as regards the DNA integrity index (DII). Biopsied blastocysts better tolerate vitrification than intact expanded blastocysts.

Are zona pellucida laser drilling and polar body biopsy safe for in vitro matured oocytes?

INTRODUCTION

Preconception diagnosis requires first polar body biopsy. When the hole in the zona pellucida is made with a laser beam, heat propagation could, like the biopsy itself, be deleterious. Our aim was to evaluate the effect of this technique on human in vitro matured oocyte and embryo development.

METHODS

One hunded fifty five retrieved immature oocytes from 75 women, matured in vitro, were distributed in 3 groups: 50 oocytes in a control group, without laser drilling and first polar body biopsy, 52 oocytes in a group with only laser drilling, and 53 oocytes in a group with both laser drilling and first polar body biopsy. Safety was evaluated using four criteria: [1] oocyte lysis rate, [2] oocyte activation rate, [3] oocyte development after calcium ionophore treatment, [4] and embryo chromosome breakage incidence after Tarkowski preparation.

RESULTS

No difference in the four criteria was observed between the 3 oocyte groups.

CONCLUSIONS

We did not find evidence of deleterious effect of laser drilling and first polar body biopsy on in vitro matured oocytes, according to our criteria.

What next for preimplantation genetic screening? High mitotic chromosome instability rate provides the biological basis for the low success rate

Preimplantation genetic screening is being scrutinized, as recent randomized clinical trials failed to observe the expected significant increase in live birth rates following fluorescence in situ hybridization (FISH)-based screening. Although these randomized clinical trials are criticized on their design, skills or premature stop, it is generally believed that well-designed and well-executed randomized clinical trials would resolve the debate about the potential benefit of preimplantation genetic screening. Since FISH can analyze only a limited number of chromosomal loci, some of the embryos transferred might be diagnosed as ‘normal’ but in fact be aneuploid for one or more chromosomes not tested. Hence, genome-wide array comparative genome hybridization screening enabling aneuploidy detection of all chromosomes was thought to be a first step toward a better design. We recently showed array screening indeed enables accurate determination of the copy number state of all chromosomes in a single cell. Surprisingly, however, this genome-wide array screening revealed a much higher frequency and complexity of chromosomal aberrations in early embryos than anticipated, with imbalances in a staggering 90% of all embryos. The mitotic error rate in cleavage stage embryos was proven to be higher than the meiotic aneuploidy rate and as a consequence, the genome of a single blastomere is not representative for the genome of the other cells of the embryo. Hence, potentially viable embryos will be discarded upon screening a single blastomere. This observation provides a biological basis for the failure of the randomized clinical trials to increase baby-take-home rates using FISH on cleavage stage embroys.

Approaches to improve the diagnosis and management of infertility

BACKGROUND Recent advances in our understanding of the causes of infertility and of assisted reproductive technology (ART) have led to the development of complex diagnostic tools, prognostic models and treatment options. The Third Evian Annual Reproduction (EVAR) Workshop Meeting was held on 26-27 April 2008 to evaluate evidence supporting current approaches to the diagnosis and management of infertility and to identify areas for future research efforts. METHODS Specialist reproductive medicine clinicians and scientists delivered presentations based on published literature and ongoing research on patient work-up, ovarian stimulation and embryo quality assessment during ART. This report is based on the expert presentations and subsequent group discussions and was supplemented with publications from literature searches and the authors' knowledge. RESULTS It was agreed that single embryo transfer (SET) should be used with increasing frequency in cycles of ART. Continued improvements in cryopreservation techniques, which improve pregnancy rates using supernumerary frozen embryos, are expected to augment the global uptake of SET. Adaptation and personalization of fertility therapy may help to optimize efficacy and safety outcomes for individual patients. Prognostic modelling and personalized management strategies based on individual patient characteristics may prove to represent real progress towards improved treatment. However, at present, there is limited good-quality evidence to support the use of these individualized approaches. CONCLUSIONS Greater quality control and standardization of clinical and laboratory evaluations are required to optimize ART practices and improve individual patient outcomes. Well-designed, good-quality studies are required to drive improvements to the diagnosis and management of ART processes.

Does the genetic and familial background of males undertaking ICSI affect the outcome?

Purpose

To investigate whether the success rate of ICSI is (1) related to the etiology of infertility or (2) adversely affected by a family history of potential genetic disorders.

Methods

All men with an ICSI indication in our hospital between 1994 and 2005 were included in our cohort study. Data on the ICSI process, etiology of infertility, and family history were collected. ICSI success rates of infertility subgroups and a subgroup with a positive family history were compared to a group with unknown etiology and a negative family history.

Results

There was no significant difference in clinical pregnancy or delivery rates between the subgroups. Couples achieving a pregnancy underwent significantly more ICSI cycles compared to couples not achieving a pregnancy.

Conclusion

Our results suggest that the success rate of ICSI treatment is not related to the cause of infertility or a family history positive for potential genetic disorders.