Array CGH analysis shows that aneuploidy is not related to the number of embryos generated

Diminished ovarian reserve versus ovarian aging: overlaps and differences

PURPOSE OF REVIEW

Diminished ovarian reserve, in general, implies a quantitative decline in the oocyte pool. However, whether this quantitative decline is necessarily accompanied by a qualitative decline, remains to be determined.

RECENT FINDINGS

Studies of natural conception suggest that fecundity of women with a quantitative decline in ovarian reserve is similar to age-matched women with normal ovarian reserve. Data on rates of pregnancy loss and fetal chromosomal abnormality do not consistently suggest a decline in oocyte quality in women who has a lower ovarian reserve. In assisted reproductive technology (ART) cycles, oocytes from women with diminished ovarian reserve have similar potential for euploid blastocyst development. Likewise, available evidence does not strongly suggest an increased risk of pregnancy loss in women with diminished reserve undergoing ART treatment as compared with similarly aged woman with normal ovarian reserve.

SUMMARY

Quantitative decline in ovarian reserve may not be necessarily accompanied by a qualitative decline. Although a decreased number of follicles and poor response to ovarian stimulation are hallmarks of ovarian aging, younger women with diminished ovarian reserve may not be experiencing the distinct effects of aging on oocyte quality.

Update on the management of poor ovarian response in IVF: the shift from Bologna criteria to the Poseidon concept

Despite the considerate progress to which assisted reproduction technology (ART) has been subject since 1978, some issues remain unresolved. Notably, the clinical management of patients with a poor ovarian response is still a challenge in everyday practice, frustrating to both the patient and the fertility expert. Poor ovarian responders (PORs) embody 9–24% of patients undergoing ovarian stimulation, meaning that up to one in four patients conceals a poor reproductive prognosis. The last decade has witnessed the attempts of the medical community to standardize diagnosis of POR with the developing of the Bologna Criteria and the subsequent evolution of the low prognosis patient elaborated in the POSEIDON classification. The aim of this article is to summarize all evidence concerning etiology and management of poor ovarian response, including the most recent advances and future prospects in this regard.

Interaction of acrocentric chromosome involved in translocation and sex of the carrier influences the proportion of alternate segregation in autosomal reciprocal translocations

STUDY QUESTION

Are meiotic segregation patterns of reciprocal translocations affected by the combined effect of chromosome type and carrier's sex?

SUMMARY ANSWER

Interaction of an acrocentric chromosome (Acr-ch) involved in the translocation and sex of the carrier influences the proportion of alternate segregation for normal or balanced chromosome contents during meiotic segregation in autosomal reciprocal translocations.

WHAT IS KNOWN ALREADY

Carriers of reciprocal translocations are at a significantly increased risk of fertility problems due to the generation of unbalanced gametes in meiotic segregation of a quadrivalent. Previous studies have reported that meiotic segregation patterns of a quadrivalent can be affected by factors such as a carrier's sex and age and the chromosome type. However, the reported proportion of alternate segregation does not differ significantly, except in one study, and whether combined effects between these factors exist is unclear.

STUDY DESIGN, SIZE, DURATION

A retrospective study of array comparative genomic hybridization (aCGH) outcome data from patients with autosomal reciprocal translocations was conducted to analyse meiotic segregation patterns and blastocyst euploidy rates. We enroled 473 couples whose embryos were tested between January 2013 and September 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Meiotic segregation patterns of 2101 blastocysts from 243 female carriers, including 76 cases with translocations involving Acr-ch, and 230 male carriers, including 88 cases with translocations involving Acr-ch, were analysed according to chromosome type, carrier's sex and age.

MAIN RESULTS AND THE ROLE OF CHANCE

In cases with translocations involving the Acr-ch subgroup, the proportion of alternate segregation (53.9 vs 33.4%, P < 0.0001) was significantly higher in male carriers than in female carriers, with the proportion of 3:1 segregation (6.8 vs 16.3%, P < 0.0001) being significantly lower. The proportions of alternate segregation were similar between sexes in cases with translocations not involving the Acr-ch subgroup. Meanwhile, in the female carrier subgroup, the proportion of alternate segregation (33.4 vs 45.2%, P < 0.001) was significantly lower and the proportion of 3:1 segregation (16.3 vs 8.2%, P < 0.001) was significantly higher in cases with translocations involving Acr-ch than in those not. In the male carrier subgroup, the proportion of alternate segregation (53.9 vs 46.9%, P = 0.031) was higher and the proportion of adjacent-1 segregation (27.1 vs 37.3%, P < 0.001) was significantly lower in cases with translocations involving Acr-ch than in those not. Carrier's age did not affect the meiotic segregation patterns. However the euploidy rates were significantly lower in couples with advanced compared to young maternal age respectively.

LIMITATIONS, REASONS FOR CAUTION

Mosaic embryos were not identified using aCGH in this study. Patients with complex chromosome rearrangements and translocations involving sex chromosomes were excluded. Interchromosomal effect was not analysed.

WIDER IMPLICATIONS OF THE FINDINGS

The findings of this study provide detailed information for genetic counselling of couples with autosomal reciprocal translocations on their chances of producing euploid gametes.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by the National Key Research and Development Program of China (2016YFC1000202); the National Natural Science Foundation of China (81671522); the Natural Science Foundation of Shandong Province in China (ZR2016HP09); and the Innovative Foundation of Reproductive Hospital Affiliated to Shandong University (20171114, 20171111). No competing interests are declared.

TRIAL REGISTRATION NUMBER

N/A.

GnRH triggering may improve euploidy and live birth rate in hyper-responders: a retrospective cohort study

PURPOSE

Despite the increasing use of GnRHa to trigger final oocyte maturation in segmented IVF cycles, the effects of trigger modality on chromosomal competence and embryo quality remain controversial. Hence, the purpose of this study was to compare euploidy rates and pregnancy outcomes among hyper-responding women using hCG versus GnRHa trigger.

METHODS

This retrospective study included 333 hyper-responders, defined as >15 oocytes retrieved, who underwent preimplantation genetic testing (PGT-A) in segmented IVF cycles using either GnRHa or urinary hCG trigger. Live birth rate (LBR) was the primary outcome of interest. Implantation rate (IR), clinical pregnancy rate (CPR), and euploidy rate were secondary outcomes.

RESULTS

GnRH triggering was associated with improved IR (70.5 vs. 53.2%, p = 0.0475), LBR (51.3 vs. 33.8%, p = 0.0170) compared to hCG. A greater number of oocytes were retrieved (21.9 vs 18.4%, p < 0.001) and euploid embryos produced (2.8 vs. 2.1, p = 0.0109) after GnRHa triggering, while higher euploidy rates were only observed among women <35-years-old (62.0 vs. 51.7%, p = 0.0307) using GnRHa trigger. Higher OHSS rates were observed after hCG triggering (10.6 vs. 2.1%, p = 0.0009).

CONCLUSION

Hyper-responders who received GnRHa trigger experienced improved pregnancy outcomes and lower rates of OHSS compared to hCG triggering. The higher number of oocytes retrieved and euploid embryos produced may reflect an improved developmental competence using GnRHa triggering due to physiologic induction of both LH and FSH surge or other undefined mechanisms that improve embryo development. However, higher overall euploid rates were only observed among women <35-years-old using the GnRHa trigger. Further prospective studies are required to validate this observation and evaluate the specific influence of different ovulation triggers on gamete developmental competence among hyper-responder women.

Novel Physiology and Definition of Poor Ovarian Response; Clinical Recommendations

Poor ovarian response (POR) to controlled ovarian stimulation (OS) presents a major challenge in assisted reproduction. The Bologna criteria represented the first serious attempt to set clear criteria for the definition of POR. However, the Bologna criteria were questioned because of the persistent heterogeneity among POR patients and the inability to provide management strategies. Based on these facts, a more recent classification, the POSEIDON (Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number) classification, was developed to provide a homogeneous and refined definition of POR that significantly reduces the heterogeneity of the Bologna criteria definition of POR and helps in the clinical handling and counseling of patients. In this review, we discuss the impact of the POSEIDON classification on the clinical management of patients with POR.

Factors Associated with Ovarian Hyperstimulation Syndrome (OHSS) Severity in Women With Polycystic Ovary Syndrome Undergoing IVF/ICSI

INTRODUCTION

Age, polycystic ovary syndrome (PCOS), low body mass index (BMI), high antral follicle count (AFC), increased anti-Muller hormone (AMH) levels, and elevated serum estradiol (E2) concentrations are risk factors for ovarian hyperstimulation syndrome (OHSS). However, data on the relationship between risk factors and OHSS severity in patients with PCOS are rare.

OBJECTIVE

This retrospective study examined the risk factors for OHSS and their effect on OHSS severity in patients with PCOS undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI).

METHOD

The records of 2,699 women were reviewed and included in this study. These women were diagnosed with PCOS during their first IVF/ICSI cycle between January 2010 and December 2017. We analyzed the association between each of the interrogated risk factors (including female age, BMI, AFC, basal serum E2, and the number of oocytes retrieved) and OHSS. The effects of each risk factor on OHSS severity were further explored. Logistic regression was performed as part of the above analysis.

RESULTS

Of the 2,699 women with PCOS who underwent assisted reproductive technology (ART), 75.2% had a normal response to controlled ovarian hyperstimulation (COH), while 24.8% developed OHSS. All OHSS patients were younger and had lower BMIs and basal serum follicle-stimulating hormone (FSH) and E2 levels but higher AFCs than those in the normal group. AFC demonstrated a strong correlation with OHSS, with a cutoff value of 24 in patients with PCOS. A total of 19.5% of the patients had mild OHSS, while 80.5% had moderate OHSS. Compared with those in the moderate OHSS group, those in the mild OHSS group were older and had higher basal serum FSH levels and lower serum E2 and T levels. However, BMI and AFC were not different between the mild and moderate OHSS groups. Basal serum E2 showed a strong correlation with OHSS severity, with a cutoff value of 37.94 pg/ml.

CONCLUSIONS

AFC is a strong marker of OHSS, and basal serum E2 is the best predictor of OHSS severity in women with PCOS undergoing IVF treatment.

Management Strategies for POSEIDON Group 2

Although individualization of ovarian stimulation aims at maximal efficacy and safety in assisted reproductive treatments, in its current form it is far from ideal in achieving the desired success in women with a low prognosis. This could be due a failure to identify such women who are likely to have a low prognosis with currently used prognostic characteristics. Introduction of the patient-oriented strategies encompassing individualized oocyte number (POSEIDON) concept reinforces recognizing such low prognosis groups and stratifying in accordance with important prognostic factors. The POSEIDON concept provides a practical approach to the management of these women and is a useful tool for both counseling and clinical management. In this commentary, we focus on likely management strategies for POSEIDON group 2 criteria.

Ovarian stimulation for freeze-all IVF cycles: a systematic review

BACKGROUND

Freeze-all IVF cycles are becoming increasingly prevalent for a variety of clinical indications. However, the actual treatment objectives and preferred treatment regimens for freeze-all cycles have not been clearly established.

OBJECTIVE AND RATIONALE

We aimed to conduct a systematic review of all aspects of ovarian stimulation for freeze-all cycles.

SEARCH METHODS

A comprehensive search in Medline, Embase and The Cochrane Library was performed. The search strategy included keywords related to freeze-all, cycle segmentation, cumulative live birth rate, preimplantation genetic diagnosis, preimplantation genetic testing for aneuploidy, fertility preservation, oocyte donation and frozen-thawed embryo transfer. We included relevant studies published in English from 2000 to 2018.

OUTCOMES

Our search generated 3292 records. Overall, 69 articles were included in the final review. Good-quality evidence indicates that in freeze-all cycles the cumulative live birth rate increases as the number of oocytes retrieved increases. Although the risk of severe ovarian hyperstimulation syndrome (OHSS) is virtually eliminated in freeze-all cycles, there are certain risks associated with retrieval of large oocyte cohorts. Therefore, ovarian stimulation should be planned to yield between 15 and 20 oocytes. The early follicular phase is currently the preferred starting point for ovarian stimulation, although luteal phase stimulation can be used if necessary. The improved safety associated with the GnRH antagonist regimen makes it the regimen of choice for ovarian stimulation in freeze-all cycles. Ovulation triggering with a GnRH agonist almost completely eliminates the risk of OHSS without affecting oocyte and embryo quality and is therefore the trigger of choice. The addition of low-dose hCG in a dual trigger has been suggested to improve oocyte and embryo quality, but further research in freeze-all cycles is required. Moderate-quality evidence indicates that in freeze-all cycles, a moderate delay of 2–3 days in ovulation triggering may result in the retrieval of an increased number of mature oocytes without impairing the pregnancy rate. There are no high-quality studies evaluating the effects of sustained supraphysiological estradiol (E2) levels on the safety and efficacy of freeze-all cycles. However, no significant adverse effects have been described. There is conflicting evidence regarding the effect of late follicular progesterone elevation in freeze-all cycles.

WIDER IMPLICATIONS

Ovarian stimulation for freeze-all cycles is different in many aspects from conventional stimulation for fresh IVF cycles. Optimisation of ovarian stimulation for freeze-all cycles should result in enhanced treatment safety along with improved cumulative live birth rates and should become the focus of future studies.

The combined impact of maternal age and body mass index on cumulative live birth following in vitro fertilization

BACKGROUND

It is critical to evaluate the combined impact of age and body mass index on the cumulative likelihood of live birth following in vitro fertilization, as achieving a lower body mass index before infertility treatment often is recommended for women with overweight and obesity. It is important to consider whether achieving a particular body mass index, thus resulting in an older age at in vitro fertilization cycle start, is beneficial or harmful to the likelihood of live birth.

OBJECTIVES

To evaluate the combined impact of age and body mass index on the cumulative live birth rate following in vitro fertilization to inform when delaying in vitro fertilization treatment to achieve a lower body mass index may be beneficial or detrimental to the likelihood of live birth.

STUDY DESIGN

This is a retrospective study using linked fresh and cryopreserved/frozen cycles from January 2014 to December 2015 from the Society for Reproductive Technology Clinic Outcome Reporting System, representing >90% of in vitro fertilization cycles performed in the United States. The primary outcome was live birth as measured by cumulative live birth rate. Secondary outcomes included implantation rate, clinical pregnancy rate, and miscarriage rate. Poisson and logistic regression were used to calculate risk and odds ratios with 95% confidence intervals to determine differences in implantation, clinical pregnancy, and miscarriage, as appropriate, among first fresh in vitro fertilization cycles compared across age (years) and body mass index (kg/m²) categories. Cox regression was used to calculate hazard ratios with 95% confidence intervals to determine differences in the cumulative live birth rate using fresh plus linked frozen embryo transfer cycles.

RESULTS

There were 51,959 first fresh cycles using autologous eggs and 16,067 subsequent frozen embryo transfer cycles. There were 21,395 live births, for an overall cumulative live birth rate of 41.2% per cycle start. The implantation rate, clinical pregnancy rate, and cumulative live birth rate decreased with increasing body mass index and age, and the miscarriage rate increased with increasing body mass index and age (linear trend P<.001 for all). Body mass index had a greater influence on live birth at younger ages as compared with older ages.

CONCLUSIONS

Age-related decline in fertility has a greater impact than body mass index on the cumulative live birth rate at older ages, suggesting that taking time to achieve lower body mass index before in vitro fertilization may be detrimental for older women with overweight or obesity. Delaying conception to lose weight before in vitro fertilization should be informed by the combination of age and body mass index.

Preimplantation genetic testing for aneuploidy versus morphology as selection criteria for single frozen-thawed embryo transfer in good-prognosis patients: a multicenter randomized clinical trial

OBJECTIVE

To evaluate the benefit of next-generation sequencing (NGS)-based preimplantation genetic testing for aneuploidy (PGT-A) for embryo selection in frozen-thawed embryo transfer.

DESIGN

Randomized controlled trial.

SETTING

Not applicable.

PATIENT(S)

Women aged 25-40 years undergoing IVF with at least two blastocysts that could be biopsied.

INTERVENTION(S)

Randomization for single frozen-thawed embryo transfer with embryo selection based on PGT-A euploid status versus morphology.

MAIN OUTCOME MEASURE(S)

Ongoing pregnancy rate (OPR) at 20 weeks' gestation per embryo transfer.

RESULT(S)

A total of 661 women (average age 33.7 ± 3.6 years) were randomized to PGT-A (n = 330) or morphology alone (n = 331). The OPR was equivalent between the two arms, with no significant difference per embryo transfer (50% [137/274] vs. 46% [143/313]) or per intention to treat (ITT) at randomization (41.8% [138/330] vs. 43.5% [144/331]). Post hoc analysis of women aged 35-40 years showed a significant increase in OPR per embryo transfer (51% [62/122] vs. 37% [54/145]) but not per ITT.

CONCLUSION(S)

PGT-A did not improve overall pregnancy outcomes in all women, as analyzed per embryo transfer or per ITT. There was a significant increase in OPR per embryo transfer with the use of PGT-A in the subgroup of women aged 35-40 years who had two or more embryos that could be biopsied, but this was not significant when analyzed by ITT.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02268786.

Is more better? A higher oocyte yield is independently associated with more day-3 euploid embryos after ICSI

STUDY QUESTION

Is the number of oocytes retrieved after ovarian stimulation for ICSI independently associated with the number of day-3 euploid embryos (EE)?

SUMMARY ANSWER

A larger oocyte yield is independently associated with more day-3 EE, although the expected benefit decreases significantly with advancing age.

WHAT IS KNOWN ALREADY

Although traditionally ovarian stimulation aims at collecting more than one oocyte in order to increase the chance of pregnancy, there is evidence suggesting that excessive ovarian response leads to lower live birth rates. Whether a larger oocyte yield after ovarian stimulation is associated with the genetic composition of the resulting embryos and therefore with their reproductive potential is still largely unknown.

STUDY DESIGN, SIZE, DURATION

This is a multi-centered retrospective cohort study analyzing 724 cycles of preimplantation genetic testing for aneuploidy (PGT-A) cycles using day-3 biopsy and array-comparative genomic hybridization between March 2011 and December 2016 in three laboratories.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The primary outcome measure was the number of EE on day-3. Statistical analysis was performed using the generalized estimating equations (GEE) framework and multivariate regression models to control for the clustered nature of the data while adjusting for potential confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

A multivariate regression GEE model including all significant population and stimulation characteristics as covariates as well as an interaction term between female age and number of oocytes revealed that the number of oocytes retrieved was still positively associated with the number of EE (coeff: +0.40, 95% CI: 0.24-0.56). The interaction term was highly significant (coeff: -0.01, P < 0.001) indicating an effect modifying role of female age on the association of oocytes retrieved with the number of EE. The number of oocytes retrieved was also positively associated with cumulative live birth rates (odds ratio: 1.07, 95% CI: 1.03-1.12).

LIMITATIONS, REASONS FOR CAUTION

This study is retrospective and the presence of residual unknown bias cannot be excluded. Furthermore, the population analyzed in this study might not be completely representative of the general population undergoing ICSI.

WIDER IMPLICATIONS OF THE FINDINGS

These results provide an explanatory mechanism for the recently published positive association between the number of oocytes retrieved and cumulative live birth rates.

STUDY FUNDING/COMPETING INTEREST(S)

CAV is supported by a NHMRC Early Career Fellowship (GNT1147154)/ No competing interests to declare.

A prospective study of non-invasive preimplantation genetic testing for aneuploidies (NiPGT-A) using next-generation sequencing (NGS) on spent culture media (SCM)

PURPOSE

This study was to evaluate if spent culture media (SCM) of embryos could be used as a non-invasive tool to achieve aneuploidy screening. Ploidy calls, as well as concordance rates between PGT-A results from trophectoderm (TE) and SCM, were compared. Clinical outcomes of single euploid transfers were also evaluated.

METHODS

The study was conducted from March 2017 to June 2018 in a university-based ART center. SCM of day 3 to the day(s) of TE biopsy of all biopsied blastocysts were collected for testing. PGT-A results of SCM were compared with the standard results of TE, with clinical relevance and outcomes examined.

RESULTS

NiPGT-A using SCM gave a sensitivity of 81.6%, specificity of 48.3%, positive predictive value of 82.6%, and negative predictive value of 46.7% in ploidy calling. The concordance rates for autosomes and sex determination were 62.1% and 82.4%, respectively. There were 14 single embryo transfer cycles of euploids as determined by TE biopsy. Clinical outcomes not only confirmed 3 false positive results from SCM but also reflected the true ploidy status of the transferred embryo in one case. If ploidy calls were dichotomized without mosaic embryos, the sensitivity and NPV would increase to 91.0% and 66.7% (p = 0.60 and p = 0.25), respectively.

CONCLUSIONS

Cell-free DNA found in SCM could provide ploidy information of an embryo as in PGT-A from its TE. Given its potential to reflect the comprehensive chromosomal profile of the whole embryo, more research based on clinical outcomes is required to determine if SCM could be a reliable selection tool in PGT-A.

Is there an association between oocyte number and embryo quality? A systematic review and meta-analysis

This systematic review and meta-analysis determined the association between aspirated after ovarian stimulation and top/good quality embryos obtained in women undergoing ovarian stimulation for IVF/intracytoplasmic sperm injection (ICSI). MEDLINE, EMBASE, Scopus, CINAHL and Web of Science were searched for English-language publications on top/good-quality embryos at cleavage (day 2/3) and/or blastocyst (day 5/6) developmental stages, up to 18 November 2017. Twenty-eight studies (three prospective and 25 retrospective) reporting data on 291,752 assisted reproductive technology (ART) cycles were considered eligible. We confirmed a strong positive association between oocytes retrieved and top/good-quality day 2/3 embryos (weighted correlation coefficient [r_w] = 0.791), day 5/6 embryos (r_w = 0.901), metaphase II oocytes (r_w = 0.988), oocytes exhibiting two pronuclei (r_w = 0.987) and euploid embryos (r_w = 0.851); P < 0.001 for all correlations (evaluated in subsets of the 17 studies). Data from 5657 cycles showed that the group with the most oocytes aspirated had the most top/good-quality day 2/3 embryos (pooled standardized mean differences (high [>15] versus low [<4] 1.91, 95% confidence interval [CI] 1.05-2.77, P < 0.0001; high versus medium [4-15] 1.15, 95% CI 0.74-1.55, P < 0.0001; medium versus low 1.41, 95% CI 0.79-2.03, P < 0.0001). Individual participant meta-analysis would enable accurate determination of these associations and other outcomes.

Role of aneuploidy screening in preimplantation genetic testing for monogenic diseases in young women

OBJECTIVE

To investigate whether aneuploidy screening in preimplantation genetic testing (PGT) for monogenic diseases improves the ongoing pregnancy/live birth rate of single frozen/thawed embryo transfer (FET) cycles in young women.

DESIGN

Retrospective cohort study.

SETTING

Single university-based fertility center.

PATIENT(S)

From January 2016 to December 2017, 569 FET cycles were selected for analysis. The aneuploidy screening (AS) group included 131 FET cycles from 105 oocyte retrieval cycles in 98 patients who underwent PGT for monogenic diseases with aneuploidy screening, and the non-AS group included 438 FET cycles from 280 oocyte retrieval cycles in 266 patients who underwent PGT for monogenic diseases without aneuploidy screening.

INTERVENTION(S)

The patient population was all under the age of 35 years and underwent PGT for monogenic diseases with and without AS.

MAIN OUTCOME MEASURE(S)

Ongoing pregnancy/live birth rate, live birth rate, implantation rate, and miscarriage rate.

RESULT(S)

Aneuploidy screening significantly improved the ongoing pregnancy/live birth rate (61.22% vs. 43.98%), implantation rate (64.29% vs. 50.38%), and live birth rate (53.06% vs. 36.09%) of young women carrying monogenic diseases in the first FET cycles. When adjusted for the parity, number of previous miscarriages, and percentage of infertility, the likelihood of implantation was 1.874 times higher (95% confidence interval 1.126-3.119), and an ongoing pregnancy/live birth was 2.139 times more likely (95% confidence interval 1.295-3.534). In addition, the miscarriage rate was significantly decreased (3.17% vs. 11.94%). In the cumulative pregnancy outcomes, the cumulative ongoing pregnancy/live birth rate both per transfer and per patient were significantly higher in the AS group (62.24% vs. 50.38% and 79.59% vs. 68.80%), but no difference existed after adjusting for the parity, number of previous miscarriage, and percentage of infertility. Nevertheless, aneuploidy screening reduced the time interval from the first ET to the achievement a pregnancy.

CONCLUSION(S)

Aneuploidy screening in PGT significantly improved the ongoing pregnancy/live birth rate of young women carrying monogenic diseases in the first FET cycles.

Ovarian stimulation for preimplantation genetic testing

A narrative review of the management of controlled ovarian stimulation in patients undergoing preimplantation genetic testing is presented. An electronic search was performed to identify research publications that addressed ovarian stimulation and preimplantation genetic testing published until December 2017. Studies were classified in decreasing categories: randomized controlled trials, prospective controlled trials, prospective non-controlled trials, retrospective studies and experimental studies. The aim of controlled ovarian stimulation has shifted from obtaining embryos available for transfer to yielding the maximum embryos available for biopsy to increase the odds of achieving one euploid embryo available for transfer, without the distress of inducing ovarian hyperstimulation syndrome or inadequate endometrium receptivity as vitrification and deferred embryo transfer usually will be planned. The present narrative review summarizes all treatment-related variables as well as stimulation strategies after controlled ovarian stimulation that could help patients undergoing an in vitro fertilization cycle coupled with preimplantation genetic testing, including the number of oocytes needed to achieve one healthy live birth, oral contraceptive pill usage, the role of mild ovarian stimulation or random-start stimulation, the stimulation protocol and type of gonadotropin of choice, the novel progesterone protocols, agonist or dual trigger as a final oocyte maturation trigger, the accumulation of oocytes/embryos and the optimal interval before proceeding with a subsequent controlled ovarian stimulation or the optimal medication to link stimulation cycles. The discussion is being presented according to how questions are posed in clinical practice. The aim of ovarian stimulation has shifted from obtaining embryos available for transfer to yielding the maximum embryos available for biopsy to increase the odds of achieving one euploid embryo available for transfer.

Current status of spent embryo media research for preimplantation genetic testing

In recent years, a growing body of literature has emerged investigating the clinical utility of spent embryo media (SEM) for preimplantation genetic testing for aneuploidy (PGT-A) (Hammond et al. in Fertil Steril. 107(1):220-8, 2017; Xu et al. in Proc Natl Acad Sci USA. 113(42):11907-12, 2016; Shamonki et al. in Fertil Steril. 106(6):1312-8, 2016; Feichtinger et al. in Reprod BioMed Online. 34(6):583-9, 2017; Vera-Rodriguez et al. in Hum Reprod. 33(4):745-56, 2018; Kuznyetsov et al. in PLoS One. 13(5):e0197262, 2018; Ho et al. in Fertil Steril. 110(3):467-75, 2018; Capalbo et al. in Fertil Steril. 110(5):870-9, 2018). Most of these studies have reported moderate success rates, suggesting the need for improvements in sensitivity and specificity. The concordance between spent media and embryo biopsy or whole embryo was reported to be between 30.4 and 90%, with 50-70% correlation being the most representative (Xu et al. in Proc Natl Acad Sci USA. 113(42):11907-12, 2016; Shamonki et al. in Fertil Steril. 106(6):1312-8, 2016; Feichtinger et al. in Reprod BioMed Online. 34(6):583-9, 2017; Vera-Rodriguez et al. in Hum Reprod. 33(4):745-56, 2018; Kuznyetsov et al. in PLoS One. 13(5):e0197262, 2018; Ho et al. in Fertil Steril. 110(3):467-75, 2018). Here, we will analyze all spent media testing strategies including SEM collection methods, whole genome amplification (WGA) strategies, chromosome copy number detection, and bioinformatics analysis tools. We will propose improvements to further increase the accuracy and sensitivity of the assay before bringing PGT-A with SEM into the clinical sphere.

Practical Considerations in Providing Preimplantation Genetic Testing for Aneuploidies (PGT-A)

Preimplantation genetic testing for aneuploidies (PGT-A) has been controversial in its application to improve reproductive success, reduce time-to-pregnancy, and serve the intention-to-treat. Nevertheless, many in vitro fertilization (IVF) units have already introduced the service for one reason or another. Given PGT-A is not a stand-alone technique but a clinical service involving several disciplines, this mini review discussed the factors that can influence success rates when PGT-A is applied and highlighted practical issues encountered by clinicians, embryology, and genetics laboratories involved in the provision of PGT-A service.

A Novel Predictive Model to Estimate the Number of Mature Oocytes Required for Obtaining at Least One Euploid Blastocyst for Transfer in Couples Undergoing in vitro Fertilization/Intracytoplasmic Sperm Injection: The ART Calculator

The POSEIDON group (Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number) has introduced "the ability to retrieve the number of oocytes needed to achieve at least one euploid embryo for transfer" as an intermediate marker of successful outcome in IVF/ICSI cycles. This study aimed to develop a novel calculator to predict the POSEIDON marker. We analyzed clinical and embryonic data of infertile couples who underwent IVF/ICSI with the intention to have trophectoderm biopsy for preimplantation genetic testing for aneuploidy. We used the negative binomial distribution to model the number of euploid blastocysts and the adaptive LASSO (Least Absolute Shrinkage and Selection Operator) method for variable selection. The fitted model selected female age, sperm source used for ICSI, and the number of mature (metaphase II) oocytes as predictors (p < 0.0001). Female age was the most important factor for predicting the probability of a blastocyst being euploid given each mature oocyte (loglikelihood of age [adjusted for sperm source]: 30.9; df = 2; p < 0.0001). The final predictive model was developed using logistic regression analysis, and internally validated by the holdout method. The predictive ability of the model was assessed by the ROC curve, which resulted in an area under the curve of 0.716. Using the final model and mathematical equations, we calculated the individualized probability of blastocyst euploidy per mature retrieved oocyte and the minimum number of mature oocytes required to obtain ≥1 euploid blastocyst-with their 95% confidence interval [CI]-for different probabilities of success. The estimated predicted probabilities of a mature oocyte turn into a euploid blastocyst decreased progressively with female age and was negatively modulated overall by use of testicular sperm across age (p < 0.001). A calculator was developed to make two types of predictions automatically, one using pretreatment information to estimate the minimum number of mature oocytes to achieve ≥1 euploid blastocyst, and another based on the actual number of mature oocytes collected/accumulated to estimate the chances of having a euploid blastocyst using that oocyte cohort for IVF/ICSI. The new ART calculator may assist in clinical counseling and individualized treatment planning regarding the number of oocytes required for at least one euploid blastocyst in IVF/ICSI procedures.

Cumulative live birth rates according to the number of oocytes retrieved after the first ovarian stimulation for in vitro fertilization/intracytoplasmic sperm injection: a multicenter multinational analysis including ∼15,000 women

OBJECTIVE

To evaluate the association between the number of oocytes retrieved and cumulative live birth rates.

DESIGN

Retrospective multicenter analysis using individual patient data.

SETTING

Tertiary referral hospitals.

PATIENT(S)

In total, 14,469 patients were analyzed. The study included the first cycle of patients stimulated for IVF/intracytoplasmic sperm injection (ICSI) from 2009 to 2014. All patients included in the analysis had either delivered a baby or had used all their embryos after their first stimulated cycle. All patients had vitrification as cryopreservation method. All women were followed up for at least 2 years.

INTERVENTION(S)

Ovarian stimulation with GnRH antagonist protocol for IVF/ICSI.

MAIN OUTCOME MEASURE(S)

The primary outcome was the cumulative live birth rate defined as the delivery of at least one live-born infant (>24 weeks of gestation) in the fresh or in the subsequent frozen-thawed cycles in relation to the number of oocytes retrieved. Only the first delivery was considered in the analysis. The secondary outcome was live birth after the fresh IVF/ICSI cycle only.

RESULT(S)

Cumulative live birth rates steadily increased with the number of oocytes, reaching 70% when ≥25 oocytes were retrieved. Interestingly, no plateau in cumulative live birth rates was observed, but a moderate increase of 5.1% on average was detected beyond 27 oocytes. Regarding the fresh cycle outcome, live birth probability increased up to seven oocytes retrieved and remained relatively unchanged (increase or decrease of ≤5%) between seven and 20 oocytes retrieved. However, a drop in fresh live birth rates was identified thereafter, which could be attributed to the progressive increase in "freeze-all" cycle rate with the number of oocytes retrieved, exceeding 20% in patients with >20 oocytes retrieved.

CONCLUSION(S)

This is the largest multicenter study evaluating for the first time the impact of ovarian response on cumulative live birth rate. The significant progressive increase of cumulative live birth rate with the number of oocytes in our study suggests that ovarian stimulation may not have a detrimental effect on oocyte/embryo quality in good-prognosis women less than 40 year old. Nevertheless, although very high ovarian response may further increase cumulative live birth rates, ovarian stimulation should be rational and avoid extreme response in terms of oocytes retrieved to preserve patients' convenience and safety and avoid ovarian hyperstimulation syndrome or other iatrogenic complications.

Prediction of live birth and cumulative live birth rates in freeze-all-IVF treatment of a general population

PURPOSE

To investigate the cumulative live birth (cLB) rate of one complete freeze-all-IVF cycle in a general infertile population and to investigate patient and treatment variables that predict blastocyst development and live birth (LB).

METHOD

In a retrospective observational study, the data of all IVF cycles performed between 1 February 2015 and 31 January 2016 at a single IVF centre was investigated. In the study, patient-couples were followed up for 18 months following oocyte retrieval. After exclusions, the patient and treatment variables of 1582 patient-couples who underwent treatment were included in the analyses.

RESULTS

The median time interval between the oocyte retrieval attempt and the frozen embryo transfer (FET) in which LB was achieved was 38.0 (35.0-67.0) days. The variables of freeze-all-IVF cycles with single blastocyst FET selected by multiple logistic regression to predict LB significantly were female age, infertility duration, FET number (i.e. 1st, 2nd, or ≥ 3rd FET), and blastocyst quality. In a regression adjusting for female age, the number of blastocysts transferred, and oocyte number group (1-3, 4-9, 10-15, and > 15), none of the oocyte number groups were selected to predict LB of 1st FET, significantly. While the per transfer LB rates decreased linearly from the 1st (56.5%) to the 3rd (36.4%) FET, the cLB rate increased from 47.3% after the 1st FET to 55.0% after a 3rd possible FET.

CONCLUSION

The cLB rate of one complete freeze-all-IVF cycle of a general infertile population, with 18-month follow-up, was 55.0%. In freeze-all-IVF, ovarian reserve variables were not selected by regression models to predict LB, significantly.

The incidence of unexpected poor ovarian response in Chinese young women

Unexpected poor ovarian response (UPOR) is a problem for both clinicians and infertile couples, because our understanding of this situation is limited. This article investigated incidence of UPOR in women <35 years with normal ovarian reserve function with further analysis.This is a retrospective study, which included 567 women who accepted their first IVF-ET/ICSI. Based on the number of oocytes retrieved, clinic pregnancy rate of fresh cycle, and cycle cancellation rate of fresh cycle, the included cycles were divided into three groups namely unexpected poor ovarian response (UPOR) (n = 120), for which number of oocytes retrieved was not more than 6; normal ovarian response (NOR) (n = 223), for which number of oocytes retrieved was between 7 and 12; and unexpected high ovarian response (UHOR) (n = 224), for which the number of oocytes retrieved was 13 at least. The comparisons of clinical outcomes and correlated hormones among groups were carried out.The incidence of UPOR in Chinese women is 21.16%. Patient age (χ = 6.177, P = .0129), basic FSH (χ = 20.585, P < .0001), basic LH (χ = 11.689, P = .0006), and AFC (χ = 8.053, P = .0045) might be helpful for diagnosis of UPOR.The basic evaluation of ovarian function may no longer be simplified into normal and abnormal ovarian reserve function; rather, by using a detailed numerical analysis, such as basal FSH and LH levels, the ovarian response to ovulation induction may be predicted to some extent.

Pregnancy rates after pre-implantation genetic screening for aneuploidy are only superior when trophectoderm biopsy is performed on hatching embryos

PURPOSE

In vitro fertilization with trophectoderm embryo biopsy and pre-implantation genetic screening with comprehensive chromosomal screening (PGS-CCS) for aneuploidy is becoming increasingly more popular. Embryos are cryopreserved and implanted in a subsequent frozen thawed embryo transfer cycle (FET). No studies have investigated differences in pregnancy outcomes by timing of trophectoderm biopsy relative to stages of blastocyst development.

METHODS

Retrospective study of all patients (n = 363) at a single IVF center between January 1, 2013 and December 31, 2016 undergoing single embryo transfer with PGS-CCS where embryos were cryopreserved with subsequent FET. Embryo expansion and grading was assessed both at the time of biopsy and transfer. Pregnancy rates were analyzed by embryo expansion and embryo grading.

RESULTS

Implantation, clinical pregnancy, and live birth rates improved significantly with increased embryo expansion at the time of embryo biopsy (P < 0.001). Pregnancy loss decreased with increases in embryo expansion prior to biopsy (P < 0.001). Superior live birth rates with PGS-CCS were seen when embryos were hatching at the time of biopsy (p < 0.001). For fresh and frozen embryo transfers without PGS-CCS, embryo expansion did not affect pregnancy outcomes.

CONCLUSIONS

PGS-CCS significantly increases implantation and live birth rates only if embryos are hatching at the time of biopsy. The embryo biopsy itself on a non-hatching embryo significantly damages the embryo in ways which are not reflected in future embryo expansion. IVF labs should wait until embryos hatch before performing trophectoderm biopsy.

Ovarian Reserve Markers to Identify Poor Responders in the Context of Poseidon Classification

It is well-known that poor ovarian reserve is a cause of infertility, poor response to gonadotrophin stimulation and poor success rate after in vitro fertilization (IVF) cycles. Some years ago a consensus was elaborated on precise criteria which can lead to a correct identification of poor responders (the Bologna criteria). More recently, the POSEIDON group has proposed a new stratified classification of patients with low prognosis, also with the aim of providing clinical indications for the management of these patients. A literature search was carried out for studies that investigated the ability of ovarian reserve markers, in particular AMH and AFC, to predict poor ovarian response in IVF cycles; secondly, studies regarding the Bologna criteria and their prognostic value were analyzed and available literature on POSEIDON classification was reported. The most recent markers of ovarian reserve (serum AMH and ultrasound AFC) have shown to provide a direct and accurate measurement of ovarian follicle pool. These markers have generally shown comparable predictive power for ovarian response and a number of retrieved oocytes in IVF cycles. "Abnormal ovarian reserve test" is a very important parameter both in the Bologna criteria and in the POSEIDON classification. Several studies have already been published about the reproductive outcome of patients defined as poor responders according to the ESHRE Bologna criteria: all of them agree on the poor IVF outcome and low pregnancy rate of these patients. Instead, being the POSEIDON classification of very recent publication, the efficacy of the POSEIDON approach in improving management and outcomes of POR patients has yet to be tested and validated with future prospective clinical trials. Prediction of poor response may help clinicians choose the stimulation protocol with the aim of gaining patient compliance and cost reduction, and many efforts have been made by researchers in this sense, including the formulation of the Bologna criteria and of the POSEIDON classification, in which the ovarian reserve markers (AMH and AFC) play a fundamental role.

Validation of ART Calculator for Predicting the Number of Metaphase II Oocytes Required for Obtaining at Least One Euploid Blastocyst for Transfer in Couples Undergoing in vitro Fertilization/Intracytoplasmic Sperm Injection

This multicenter study evaluated the reliability of the recently published ART calculator for predicting the minimum number of metaphase II (MII) oocytes (MIImin) to obtain at least one euploid blastocyst in patients undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). We used clinical and embryonic retrospective data of 1,464 consecutive infertile couples who underwent IVF/ICSI with the intention to have preimplantation genetic testing for aneuploidy. The validation procedure followed a stepwise approach. Firstly, we assessed the distribution of euploid blastocysts per patient and found that it followed a negative binomial distribution. Secondly, we used generalized linear models and applied the Lasso procedure-including MII oocytes to adjust the data-to select the factors predicting the response variable "euploid blastocyst." Third, a logistic regression model-fit to the binomial response euploid (yes/no) for each MII oocyte-was built using the relevant factors. The observational unit was the "woman" whereas the response was the pair (m, n), where n is the number of retrieved MII oocytes and m the corresponding number of euploid blastocysts. The model was internally validated by randomly splitting the data into training and validation sets. The R-squares (~0.25) and the area under the ROC curve (~0.70) did not differ between the training and validation datasets. Fourth, mathematical equations and the calculated probabilities generated by the validation model were used to determine the MIImin required for obtaining at least one euploid blastocyst according to different success probabilities. Lastly, we compared the fittings generated by the validation model and the ART calculator and assessed the predictive value of the latter using the validation dataset. The fittings were sufficiently close for both the estimated probabilities of blastocyst euploid per MII oocyte (r = 0.91) and MIImin (r = 0.88). The ART calculator positive predictive values, i.e., the frequency of patients with at least one euploid blastocyst among those who achieved the estimated MIImin, were 84.8%, 87.5%, and 90.0% for 70%, 80%, and 90% predicted probabilities of success, respectively. The ART calculator effectively predicts the MIImin needed to achieve at least one euploid blastocyst in individual patients undergoing IVF/ICSI. The prediction tool might be used for counseling and planning IVF/ICSI treatments.

In Freeze-All Strategy, Cumulative Live Birth Rate (CLBR) Is Increasing According to the Number of Blastocysts Formed in Women <40 Undergoing Intracytoplasmic Sperm Injection (ICSI)

Background: Elective freezing of all embryos, followed by frozen-thawed ET cycles emerged to prevent risk of Ovarian Hyperstimulation Syndrome and to allow endometrium recovery after Controlled Ovarian Stimulation, leading to better IVF outcomes. Blastocyst Freeze-all policy can minimize the number of abnormal embryos and consequently failed ETs, but its efficacy in terms of cumulative rates has not been studied yet. Methods: A prospective cohort observational study was carried out in Assisting Nature, Center of Assisted Reproduction and Genetics, in Thessaloniki, Greece from January 2014 until December 2017. 244 patients- normal or high responders- underwent COS with recFSH and Freeze-all policy with blastocyst culture. The included patients were 18-39 years and achieved clinical pregnancy and/or live birth or had all their vitrified blastocysts transferred in subsequent frozen-thawed cycles. Women were divided into four groups (group A: 1-2 blastocysts frozen; group B: 3-4; group C: 5-6; group D ≥7 blastocysts frozen) or seven groups (group I: 1-2 blastocysts frozen, group II: 3, group III: 4, group IV: 5, group V: 6, group VI: 7; group VII: ≥8 blastocysts frozen), according to the numerical range or to the absolute number of vitrified blastocysts, respectively. Results: The main outcome of the study was the CLBR achieved by frozen-thawed ETs, according to the number of the vitrified blastocysts. Higher CLBR are expected, when at least 3 blastocysts are formed (group B: 65.2%) and at least 2 frozen-thawed ETs are performed, reaching highest rates (88%) by group D (≥7 vitrified blastocysts). Similarly, CLBR is significantly increasing with the absolute number of the vitrified blastocysts, ranging from 20%, when 1-2 blastocysts are vitrified (group I) to 82.4% when ≥8 blastocysts are available. Conclusions: A higher number of vitrified blastocysts is associated with higher CLBR in women <40 years old- normal/high responders- following Freeze-all policy. Adopting Freeze-all strategy after blastocyst culture can contribute to improve delivery outcome after IVF, in terms of CLBR. The number of the total cryopreserved blastocysts produced might reflect the quality of the oocyte and can successfully predict the pregnancy outcome. The blastulation rate can be a robust criterion to segment or not an IVF cycle.

A Slower Age-Related Decline in Treatment Outcomes After the First Ovarian Stimulation for in vitro Fertilization in Women With Polycystic Ovary Syndrome

Background: Polycystic ovary syndrome (PCOS) patients have a better ovarian reserve and age-related improvement in endocrine disturbances than non-PCOS patients. The effects of age on in vitro fertilization (IVF) treatment outcomes associated with cumulative live birth rate (CLBR) remain unclear. Objectives: To study the effect of age on CLBR after the first ovarian stimulation in IVF in PCOS patients. Method: This retrospective cohort study included 3,502 PCOS patients and 18,596 patients with tubal factor infertility, who underwent their first IVF cycles and subsequent frozen embryo transfer (ET) attempts. The primary outcome was CLBR associated with a single stimulation cycle and secondary outcomes included the implantation rate, clinical pregnancy rate, live birth rate (LBR), large for gestational age (LGA) rate, small for gestational age (SGA) rate, and preterm birth (PTB) rate of fresh ET cycles. Results: PCOS patients over 40 years had a higher implantation rate (27.8 vs. 15.7%, P < 0.05), clinical pregnancy rate (51.4 vs. 26.1%, P < 0.05), LBR (42.3 vs. 18.2%, P < 0.05), and CLBR (50.0 vs. 21.5%, P < 0.05) than non-PCOS patients over 40 years. These rates were comparable between PCOS patients aged 35 to 40 years and those aged over 40 years (P = 0.263, 0.385, and 0.112, respectively). The changes in the implantation rate, clinical pregnancy rate, and CLBR by age were slower for PCOS patients than for non-PCOS patients (all P < 0.05). Among PCOS patients less than 35 years, BMI was negatively associated with CLBR [aOR: 0.961 (0.939-0.985); P < 0.05]; however, among PCOS patients over 35 years, instead of BMI (P = 0.353), age [aOR: 0.891 (0.803-0.990); P < 0.05] and the number of oocytes retrieved [aOR: 1.093 (1.002-1.078); P < 0.05] were significantly associated with CLBR. No significant differences in LGA, LGA, or PTB were detected between PCOS and non-PCOS patients over 35 years (all P > 0.05). Conclusions: The declines in treatment outcomes with age are slower for PCOS patients than for non-PCOS patients. For patients over 40 years, PCOS patients have reproductive advantages over non-PCOS patients. In contrast to younger PCOS patients (<35 years), older PCOS patients (≥35 years) may benefit less from taking time to lose weight before IVF treatment, and the immediate initiation of assisted reproductive treatment is essential.

The POSEIDON Criteria and Its Measure of Success Through the Eyes of Clinicians and Embryologists

This article represents a viewpoint on the POSEIDON criteria by a group of clinicians and embryologists. Its primary objective is to contextualize the Poseidon criteria and their metric of success for the relevant Frontiers Research Topic "POSEIDON's Stratification of Low Prognosis Patients in ART: The WHY, the WHAT, and the HOW". "Low prognosis" relates with reduced oocyte number, which can be associated with low or sometimes a normal ovarian reserve and is aggravated by advanced female age. These aspects will ultimately affect the number of embryos generated and consequently, the cumulative live birth rate. The novel system relies on female age, ovarian reserve markers, ovarian sensitivity to exogenous gonadotropin, and the number of oocytes retrieved, which will both identify the patients with low prognosis and stratify such patients into one of four groups of women with "expected" or "unexpected" impaired ovarian response to exogenous gonadotropin stimulation. Furthermore, the POSEIDON group introduced a new measure of clinical success in ART, namely, the ability to retrieve the number of oocytes needed to obtain at least one euploid blastocyst for transfer in each patient. Using the POSEIDON criteria, the clinician can firstly identify and classify patients who have low prognosis in ART, and secondly, aim at designing an individualized treatment plan to maximize the chances of achieving the POSEIDON measure of success in each of the four low prognosis groups. The novel POSEIDON classification system is anticipated to improve counseling and management of low prognosis patients undergoing ART, with an expected positive effect on reproductive success and a reduction in the time to live birth.

Management of Women With an Unexpected Low Ovarian Response to Gonadotropin

POSEIDON groups 1 and 2 patients respond poorly (<4 oocytes retrieved) or sub-optimally (4-9 oocytes retrieved) to gonadotropin stimulation despite the presence of adequate ovarian parameters, which negatively affect their cumulative chances of delivering a baby using Assisted Reproductive Technology. A polygenic trait involving gonadotropins and/or their receptors seems to be the primary pathophysiology mechanism explaining this phenomenon. The clinical management is mainly focused on maximizing oocyte yield as to increase the likelihood of having at least one euploid embryo for transfer. Indices such as FORT (follicle output rate) and FOI (follicle-to-oocyte index) may be used to determine if the ovarian reserve was properly explored during a previous ovarian stimulation. Testing for the presence of common polymorphisms affecting gonadotropins and/or their receptors can also be considered to identify patients at risk of hypo-response. An individualized estimation of the minimum number of oocytes needed to obtain at least one euploid embryo can assist counseling and treatment planning. Among currently existing pharmacological interventions, use of recombinant FSH in preference over urinary gonadotropin preparations, FSH dosage increase, and use of rLH supplementation may be considered -alone or combined- for optimally managing POSEIDON's groups 1 and 2 patients. However, given the recent introduction of the POSEIDON criteria, there is still a lack of studies examining the role of interventions specifically to patients classified as groups 1 and 2, thus making it an area for open research.

Recombinant luteinizing hormone supplementation in assisted reproductive technology: a systematic review

OBJECTIVE

To assess the role of recombinant human LH (r-hLH) supplementation in ovarian stimulation for ART in specific subgroups of patients.

DESIGN

Systematic review.

SETTING

Centers for reproductive care.

PATIENT(S)

Six populations were investigated: 1) women with a hyporesponse to recombinant human FSH (r-hFSH) monotherapy; 2) women at an advanced reproductive age; 3) women cotreated with the use of a GnRH antagonist; 4) women with profoundly suppressed LH levels after the administration of GnRH agonists; 5) normoresponder women to prevent ovarian hyperstimulation syndrome; and 6) women with a "poor response" to ovarian stimulation, including those who met the European Society for Human Reproduction and Embryology Bologna criteria.

INTERVENTION(S)

Systematic review.

MAIN OUTCOME MEASURE(S)

Implantation rate, number of oocytes retrieved, live birth rate, ongoing pregnancy rate, fertilization rate, and number of metaphase II oocytes.

RESULT(S)

Recombinant hLH supplementation appears to be beneficial in two subgroups of patients: 1) women with adequate prestimulation ovarian reserve parameters and an unexpected hyporesponse to r-hFSH monotherapy; and 2) women 36-39 years of age. Indeed, there is no evidence that r-hLH is beneficial in young (<35 y) normoresponders cotreated with the use of a GnRH antagonist. The use of r-hLH supplementation in women with suppressed endogenous LH levels caused by GnRH analogues and in poor responders remains controversial, whereas the use of r-hLH supplementation to prevent the development of ovarian hyperstimulation syndrome warrants further investigation.

CONCLUSION(S)

Recombinant hLH can be proposed for hyporesponders and women 36-39 years of age.

Cumulative live birth rates in in-vitro fertilization

Traditionally, in-vitro fertilization (IVF) success rates have been reported in terms of live birth per fresh cycle or embryo transfer. However, reporting IVF outcomes using cumulative live birth rates (LBR), defined as the first live birth following the use of all fresh and frozen embryos derived from a single ovarian stimulation cycle appears to be a better measure of IVF treatment success. Although there is an initial increase in fresh LBR with the number of oocytes retrieved, LBR either reach a plateau or may even decline when more than 15-20 oocytes are harvested. On the other hand, when all fresh and frozen embryos are taken into account, cumulative LBR have a significant positive association with ovarian response. Cumulative LBR are a more suitable are more comprehensive when reporting success in an IVF program. Cumulative LBR increase with the number of oocytes retrieved, suggesting that ovarian stimulation may have a minimal or no detrimental effect on oocyte/embryo quality.

Prevalence and authenticity of de-novo segmental aneuploidy (>16 Mb) in human blastocysts as detected by next-generation sequencing

RESEARCH QUESTION

What is the prevalence and authenticity of de-novo segmental aneuploidies (>16 Mb) detected by next-generation sequencing (NGS) in human preimplantation blastocysts?

DESIGN

Between April 2013 and June 2016, 5735 blastocysts from 1854 couples (average age 33.11 ± 5.65 years) underwent preimplantation genetic testing for chromosomal structural rearrangement (PGT-SR) or for aneuploidy (PGT-A) using NGS on trophectoderm (TE) biopsy samples. The prevalence of de-novo segmental aneuploidy was calculated from these results. Forty blastocysts with de-novo segmental aneuploidy detected by NGS, which had been donated for research, were warmed for further fluorescence in-situ hybridization (FISH) analysis to confirm their authenticity.

RESULTS

The frequency of de-novo segmental aneuploidies in blastocysts was 10.13% (581/5735); the phenomenon was not related to maternal age and occurred on all chromosomes. Of the 40 donated blastocysts, 39 were successfully warmed and fixed for FISH analysis at the single-cell level. The de-novo segmental aneuploidies identified by NGS were confirmed by FISH in all 39 blastocysts. However, the de-novo segmental aneuploidies in these blastocysts were not all pure patterns, with 66.67% (26/39) of blastocysts exhibiting mosaic patterns varying from 8.30% to 92.86% of cells with de-novo segmental aneuploidy. The concordance rate between NGS and FISH in TE and inner cell mass (ICM) samples was 47.69% (31/65).

CONCLUSIONS

De-novo segmental aneuploidy above 16 Mb occurred in blastocysts and could be detected by NGS, while some aneuploidies existed as mosaics in both TE and ICM.

Linking back-to-back stimulation cycles with oral contraceptives or progestins in women undergoing embryo accumulation for preimplantation genetic testing, a retrospective study

This retrospective study was carried out to determine which strategy is associated with improved outcomes in two back-to-back cycles when undergoing embryo accumulation. Eighty patients with two stimulation cycles performed with <45 days between retrievals between Jan'16-Mar'17 were included. Patients were segregated according to the strategy used to link stimulations: spontaneous menses (SM), vaginal micronized progesterone (VMP) or oral contraceptive pills (OCP). Main outcome measure was oocytes retrieved. The oocytes retrieved difference between cycles was -0.9 in SM, -1.5 in VMP and +0.4 in OCPs. Although not statistically significant, more oocytes retrieved were observed in the 2ndcycle when OCPs were used (9.0 ± 3.7 vs. 9.4 ± 4.1)? whereas fewer oocytes retrieved were observed when SM (9.4 ± 3.9 vs. 8.5 ± .0) or VMP (9.8 ± 5.7 vs. 8.2 ± 4.4) were used. After adjusting for age, gonadotropins and stimulation days (2nd cycle) and treatment group in an ANCOVA model, no treatment was associated with a higher average number of oocytes retrieved (power: 14.9%) or a higher difference of oocytes retrieved (power: 22.3%). Although no statistical significance was reached, OCPs were observed to achieve higher average and positive difference of oocytes retrieved in the 2nd cycle.

The number of biopsied trophectoderm cells may affect pregnancy outcomes

OBJECTIVE

To study if the number of trophectoderm (TE) biopsied cells has an impact on implantation rates.

DESIGN

A retrospective cohort study in a single-center study.

SETTING

In vitro fertilization center.

PATIENTS

Patients who underwent PGT-A from January 2013 to March 2016. In total, 482 vitrified/warmed single embryo transfers were included.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Clinical pregnancies rate, implantation rate.

RESULTS

Overall, clinical pregnancies per embryo transfer were higher when a regular TE were biopsied compared to larger size biopsy cells (66% (175/267) vs 53% (115/215) (p < 0.005) respectively). Pregnancy rates were also analyzed according to embryo morphology at the moment of embryo biopsy, when a good-quality embryo was transferred the clinical outcome was 75% (81/108) in group 1 and 61% (60/99) in group 2 (p < 0.05). Data was also stratified by age in patients ≤ 35 years and > 35 years. The clinical pregnancy was 67% (51/76) in women ≤ 35 years and 65% (124/191) in women > 35 years when a regular size biopsy was performed. These results significantly reduced when a larger size biopsy was performed 54% (49/91) and 53% (66/124), respectively (p < 0.05). Further investigation indicated that miscarriage rate was similar between these groups (4% (7/182) in group 1 and 5% (6/121) in group 2).

CONCLUSIONS

These findings underscore that when a large amount of TE cells are biopsied, it may negatively affect implantation rates, but once implanted, the embryos have the same chance to miscarry or reach term.

Euploidy in relation to blastocyst sex and morphology

PURPOSE

The objective of our study is to assess the relationship of embryo ploidy status in relation to embryo sex, morphological characteristics, and transfer parameters.

METHODS

This is a retrospective cohort study at an academic medical center of patients who underwent in vitro fertilization with preimplantation genetic screening (PGS) from 2010 to 2015. Embryos were screened with 24-chromosome preimplantation genetic screening with day 5/6 trophectoderm biopsy. We investigated embryo euploidy in relation to morphology (expansion, inner cell mass, trophectoderm), embryo sex, biopsy day, and blastocyst cohort size. We used multivariate logistic regression to calculate odds ratios of euploidy in relation to these parameters.

RESULTS

A total of 1559 embryos from 316 cycles and 233 patients (mean maternal age = 37.8 ± 4.2 years) were included in the analysis. Six hundred and twenty-eight blastocysts (40.3%) were found to be euploid. Expansion (p < 0.001), inner cell mass (ICM) (p < 0.01), and trophectoderm grade (p < 0.001) were significantly associated with embryo ploidy in bivariate models controlling for maternal age, while embryo sex, biopsy day, and blastocyst cohort size were not associated with embryo ploidy. In a multivariate model, we found that maternal age (p < 0.001), higher grade of expansion (p < 0.01), and better quality trophectoderm (p < 0.001 for A compared to C grade) remained significantly associated with increased embryo euploidy, but ICM grade was no longer significant. Embryo sex was not associated with ploidy status, though male embryos were found to be associated with higher trophectoderm scores (p < 0.02).

CONCLUSIONS

This is the largest study to date to investigate PGS-tested embryo sex and ploidy status. While maternal age and some morphological parameters (expansion, trophectoderm grade) are associated with euploidy in our cohort, other parameters such as embryo sex, biopsy day, and cohort size are not. Though embryo sex was not associated with euploidy, male embryos were found to be associated with higher trophectoderm grades. Additional investigation in larger studies is warranted.

Paternal age and assisted reproductive technology: problem solver or trouble maker?

In our society, the number of couples with advanced reproductive age seeking fertility treatment is increasing steadily. While the negative effect of female age on assisted reproductive technology (ART) outcomes is well established, the impact of paternal age needs to be clarified. We reviewed the current literature to determine whether advanced paternal age affects the results of ART and the health of resulting offspring. We found that the published literature is overall supportive of a positive association between advanced paternal age (>40 years) and semen quality deterioration. However, the existing evidence does not corroborate nor discard the influence of advanced paternal age on ART outcomes. Similarly, the effect of paternal age on the health of ART offspring remains equivocal, although data from naturally-conceived children clearly indicates that advanced paternal age increases the frequency of genetic, neurodevelopmental, and psychiatric diseases in the progeny. Noteworthy, the current literature is limited and subjected to bias due to the impact of maternal age as a critical confounder. Health care providers should discuss with concerned couples the available options to counteract the possible negative influence of advanced paternal age on ART outcomes and health of resulting offspring. These include identification and treatment of underlying conditions with potential negative long-term effects on fertility, sperm freezing at a young age, and use of antioxidant supplements for men at risk of excessive oxidative stress. Aged male partner from couples undergoing ART, in particular men of 50 years and older, should consider use of preimplantation genetic testing as a means to detect embryo abnormalities and select euploid embryos for transfer to the uterine cavity.

Novel approaches for diagnosis and management of low prognosis patients in assisted reproductive technology: the POSEIDON concept

The management of patients with a poor ovarian response (POR) to ovarian stimulation represents a challenging issue in reproductive medicine. Apart from economic burdens, the patient with POR has poor prognosis in assisted reproductive technology (ART), which represents a common cause of drop-out from treatment. To introduce a more nuanced picture of POR, the POSEIDON group developed novel criteria to identify and classify patients with low prognosis who undergo ART. The primary goal of POSEIDON criteria is to offer clinicians a pragmatic system to guide therapeutic management with the mindset to obtain the number of oocytes needed for improving ART success. A novel marker of ART success, namely, the ability to obtain the number of oocytes required for achieving at least one euploid embryo for transfer in each patient, is aligned with the POSEIDON criteria. A novel prediction model (ART Calculator) is developed to help clinicians estimate the POSEIDON marker of success. Furthermore, the POSEIDON criteria can also be used to identify more homogeneous populations to test in interventional trials.

Estimation of age-dependent decrease in blastocyst euploidy by next generation sequencing: development of a novel prediction model

BACKGROUND

We developed a model to estimate the female age-dependent decrease in blastocyst euploidy and the impact of blastocyst cohort size on the likelihood of having at least one euploid blastocyst for transfer.

METHODS

Retrospective analysis of 1296 trophectoderm biopsies by next-generation sequencing analysis from 436 infertile couples undergoing intracytoplasmic sperm injection and preimplantation genetic testing for aneuploidy. A logistic regression model was fit to the data. The dependent and independent variables were embryo genetic status and female age, respectively. The method of fitting was quadratic on age, and the model was validated with cross validation by a data splitting technique.

RESULTS

The decrease in the probability of blastocyst euploidy follows an age-dependent binomial distribution, progressing with every year of female age, from 1.2% to 24.5% in 28-44 years-old women (P<0.0001). The minimum number of blastocysts needed to obtain at least one euploid blastocyst for transfer was computed for different probabilities and female ages. At the age of 28 years, a total of three blastocysts is required to obtain at least one euploid blastocyst with 90% probability, whereas it is 4, 5, 6, 9, 16 and 29 for ages 35, 37, 39, 41, 43, and 45, respectively.

CONCLUSIONS

A novel prediction model estimates the probability of blastocyst euploidy and the number of blastocysts required to obtain at least one euploid embryo for transfer. This new resource based on f emale age and blastocyst cohort size will aid clinicians counsel and plan treatment of infertile couples undergoing IVF/ICSI.

Double Stimulation in the Same Ovarian Cycle (DuoStim) to Maximize the Number of Oocytes Retrieved From Poor Prognosis Patients: A Multicenter Experience and SWOT Analysis

A panel of experts known as the POSEIDON group has recently redefined the spectrum of poor responder patients and introduced the concept of suboptimal response. Since an ideal management for these patients is still missing, they highlighted the importance of tailoring the ovarian stimulation based on the chance of each woman to obtain an euploid blastocyst. Interestingly, a novel pattern of follicle recruitment has been defined: multiple waves may arise during a single ovarian cycle. This evidence opened important clinical implications for the treatment of poor responders. For instance, double stimulation in the follicular (FPS) and luteal phase (LPS) of the same ovarian cycle (DuoStim) is an intriguing option to perform two oocyte retrievals in the shortest possible time. Here, we reported our 2-year experience of DuoStim application in four private IVF centers. To date, 310 poor prognosis patients completed a DuoStim protocol and underwent IVF with blastocyst-stage preimplantation-genetic-testing. LPS resulted into a higher mean number of oocytes collected than FPS; however, their competence (i.e., fertilization, blastocyst, euploidy rates, and clinical outcomes after euploid single-embryo-transfer) was comparable. Importantly, the rate of patients obtaining at least one euploid blastocyst increased from 42.3% (n = 131/310) after FPS to 65.5% (n = 203/310) with the contribution of LPS. A summary of the putative advantages and disadvantages of DuoStim was reported here through a Strengths-Weaknesses-Opportunities-Threats analysis. The strengths of this approach make it very promising. However, more studies are needed in the future to limit its weaknesses, shed light on its putative threats, and realize its opportunities.

The dilemma of aneuploidy screening on low responders

PURPOSE OF REVIEW

Preimplantation genetic testing for aneuploidy (PGT-A) has been demonstrated to improve implantation and pregnancy rates and decrease miscarriage rates over standard morphology-based embryo selection. However, there are limited data on its efficacy in patients with diminished ovarian reserve or a poor response to stimulation who may have fewer embryos to select amongst.

RECENT FINDINGS

Early findings demonstrate that PGT-A reduces the miscarriage rate and decreases the time to delivery in poor responders. These studies highlight the importance of designing trials that compare outcomes over multiple cycles as the benefit of PGT-A in this patient population lies in eliminating the time lost to futile transfers of aneuploid embryos. Furthermore, recent studies have demonstrated that a catch-all category of 'poor responder' may need to be reevaluated as different subpopulations of patients with low response exhibit different clinical characteristics.

SUMMARY

More information is needed on characterizing the physiology of ovarian aging across multiple phenotypes of diminished ovarian reserve and establishing the predictive value of aneuploid results across multiple PGT-A platforms. However, initial data suggests benefit of PGT-A in poor responders.

Individualized controlled ovarian stimulation in expected poor-responders: an update

Controlled ovarian stimulation with subsequent multi-follicular development continues to be a keystone in ART. Evidence supports an individualized approach to ovarian stimulation, usually involving combinations of ovarian reserve tests, body mass index and age to tailor the exogenous gonadotropin dose, and potentially adjuvant treatment aiming for high safety and a shortening of time to live birth. While stimulation and trigger concepts have been developed successfully in normo- and hyperresponder patients, the poor responder patient remains difficult to manage. However, recent advances in definition and classification of the expected poor ovarian responder patient might enable a more accurate and clinically useful interpretation of new treatment concepts in a more homogenous study population. In the present review, we discuss the classification of the expected poor ovarian responder patient as well as clinically useful measurements of efficacy for controlled ovarian stimulation, and finally, we discuss the evidence for clinical management of patients with expected poor ovarian response, including adjuvant treatments such as growth hormone, androgens, and LH activity.In conclusion, the best available evidence supports that the treatment of the expected poor ovarian response patient should be individualized in all steps of ART, including the choice of GnRH analogue, the gonadotropin type and dose, ovulation trigger, and the possible use of adjuvant therapies.

A universal freeze all strategy: why it is not warranted

PURPOSE OF REVIEW

There's some preclinical evidence of an adverse effect of multifollicular growth on endometrial function in assisted reproductive technology cycles. Universal elective frozen embryo transfer (eFET) in an unstimulated cycle is being promoted as a panacea, regardless of patient, and cycle characteristics. We review the clinical evidence on the effectiveness and safety of eFETs.

RECENT FINDINGS

Randomized controlled trials (RCTs) comparing fresh and eFET yield contradictory results in terms of live birth rates. RCTs mainly involve women with an excessive response to ovarian stimulation. Studies including women with a normal or low ovarian response are either patient/physician preference or retrospective studies, prone to bias. Yet, they yield contradictory results as well. Overall, eFET seems to have limited potential to improve effectiveness of assisted reproductive technology, which could be limited to hyper-responders. Other suggested advantages of eFET include better obstetric and perinatal outcome. However, recent studies show that frozen embryo transfers can be associated with serious complications including hypertensive disorders during pregnancy, placenta accreta, or increased perinatal mortality.

SUMMARY

The evidence behind advantages of eFET is of low quality. As such, switching to a universal eFET strategy does not seem justified. New RCTs including women from different strata of ovarian response are needed.