The number and rate of euploid blastocysts in women undergoing IVF/ICSI cycles are strongly dependent on ovarian reserve and female age.

STUDY QUESTION: Can the possibility of having at least one euploid blastocyst for embryo transfer and the total number of euploid blastocysts be predicted for couples before they enter the IVF programme? SUMMARY ANSWER: Ovarian reserve and female age are the most important predictors of having at least one euploid blastocyst and the total number of euploid blastocysts. WHAT IS KNOWN ALREADY: The blastocyst euploidy rate among women undergoing ART has already been shown to significantly decrease with increasing female age, and the total number of euploid embryos is dependent on the blastocyst cohort size. However, the vast majority of published studies are based on retrospective analysis of data. STUDY DESIGN, SIZE, DURATION: This prospective analysis included 847 consecutively enrolled couples approaching their first preimplantation genetic testing for aneuploidies (PGT-A) cycle between 2017 and 2020. Only couples for whom ejaculated sperm was available and women with a BMI of <35 kg/m2 were included in the study. Only the first cycle was included for each patient. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study was conducted at an IVF centre where, for all patients, the planned treatment was to obtain embryos at the blastocyst stage for the PGT-A programme. The impact of the following covariates was investigated: a woman's serum AMH level, age, height, weight and BMI and a man's age, height, weight, BMI, sperm volume and sperm motility and morphology. The analysis was performed with a machine learning (ML) approach. Models were fit on the training set (677 patients) and their predictive performance was then evaluated on the test set (170 patients). MAIN RESULTS AND ROLE OF CHANCE: After ovarian stimulation and oocyte insemination, 40.1% of couples had at least one blastocyst available for the PGT-A. Of 1068 blastocysts analysed, 33.6% were euploid. Two distinct ML models were fit: one for the probability of having at least one euploid blastocyst and one for the number of euploid blastocysts obtained. In the training set of patients, the variable importance plots of both models indicated that AMH and the woman's age are by far the most important predictors. Specifically, a positive association between the outcome and AMH and a negative association between the outcome and female age appeared. Gradient-boosted modelling offers a greater predictive performance than generalized additive models (GAMs). LIMITATIONS, REASONS FOR CAUTION: The study was performed based on data from a single centre. While this provides a robust set of data with a constant ART process and laboratory practice, the model might be suitable only for the evaluated population, which may limit the generalization of the model to other populations. WIDER IMPLICATIONS OF THE FINDINGS: ML models indicate that for couples entering the IVF/PGT-A programme, ovarian reserve, which is known to vary with age, is the most important predictor of having at least one euploid embryo. According to the GAM, the probability of a 30-year-old woman having at least one euploid embryo is 28% or 47% if her AMH level is 1 or 3 ng/ml, respectively; if the woman is 40 years old, this probability is 18% with an AMH of 1 ng/ml and 30% with an AMH of 3 ng/ml. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by an unrestricted grant from Gedeon Richter. The authors declared no conflict of interests. TRIAL REGISTRATION NUMBER: N/A.

Which factors influence the success rate of egg donation programmes with imported vitrified oocytes?

RESEARCH QUESTION: Which factors influence the success rate of egg donation programmes with imported vitrified oocytes? DESIGN: Observational longitudinal cohort study of 431 oocyte donation cycles conducted between January 2015 and February 2019. A total of 398 couples underwent an IVF cycle with imported donated vitrified eggs. All consecutive oocyte donation cycles conducted at the Centre for Reproductive Medicine of the European Hospital in Rome, Italy, were included. RESULTS: A univariable analysis was conducted. Among the demographic characteristics studied, body mass index (BMI) was significantly able to influence outcome. In 49% of unsuccessful cycles, men were overweight, compared with 39.4% in cycles with a positive beta-HCG test (P = 0.03). The relationship between female or donor BMI and treatment outcome, however, was not statistically significant. The day on which the embryo is transferred affects the outcome of the cycle: transferring on day 2 versus day 5 reduces the probability of clinical pregnancy. The relationship between male BMI classes and semen parameters was studied: obese men have a significantly lower sperm concentration than normal-weight men (P = 0.006 after Bonferroni correction). No statistically significant differences were found in semen volume (P = 0.722), sperm morphology (P = 0.100) and motility (P = 0.179) in obese men compared with normal weight men. CONCLUSION: In addition to the number of oocytes available after warming, male BMI, semen characteristics and blastocyst transfer are critical parameters able to influence the reproductive outcomes of egg donation programmes with imported vitrified oocytes.

Can sperm quality influence embryo development and its ploidy? Analysis of 811 blastocysts obtained from different sperm sources.

The aim of our study was to evaluate the correlation between sperm quality and ploidy status of the derived blastocysts. We performed a retrospective analysis on a restricted pool of patients enrolling only those who had no female factors. Male patients with genetic factors affecting spermatogenesis were also excluded. We chose a maternal age ≤38 years to decrease the female factor, therefore the male factor was the main component of sterility. We divided the patients in four groups based on semen quality and comparing fertilization, pregnancy and euploidy rates above all. In total, 201 intracytoplasmic sperm injection (ICSI) cycles were enrolled in the study. Cycles were divided into four groups, according to semen source: normal semen, oligoasthenoteratozoospermia (OAT), cryptospermia or non-obstructive azoospermia (NOA). An extremely statistically lower fertilization rate was found in NOA patients. Unexpectedly, no differences were detected in blastocyst formation, euploidy, aneuploidy and mosaicism rates among the four groups. Interestingly, we also found a higher abortion rate comparing NOA to normal semen with an odds ratio of 4.67. In our study no statistically significant differences among the analyzed groups were found, showing little or no effect at all using spermatozoa from different semen sources or quality. This may be linked to the oocyte competence of fixing sperm DNA damage and it could be hypothesized that only sperm with a good rate of DNA integrity are able to fertilize the oocyte, explaining why poor quality semen is reflected in a low fertilization rate without effect on ploidy.

When embryology meets genetics: the definition of developmentally incompetent preimplantation embryos (DIPE)-the consensus of two Italian scientific societies.

A clear definition of developmentally incompetent preimplantation embryo (DIPE) in literature is still missing, while several scientific societies are discussing this challenging topic. From both a clinical and scientific perspective, the identification of embryos unfit for reproductive purpose is crucial. This aim should be pursued in light of all diagnostic technologies for embryo evaluation, encompassing also genetic analyses, of recent implementation in IVF. The Italian context is characterized by an unusual scenario: embryos can be discarded only if not viable and cannot be used for research purposes either. Therefore, thousands of embryos, diagnosed as affected and/or aneuploid as resulting from preimplantation genetic testing (PGT) and clinically not utilizable, are cryopreserved and stored indefinitely, with important psychological, legal, and financial implications. With the aim of updating the definition of DIPE, also on the basis of the embryo genetic status, the Italian Society of Embryology, Reproduction and Research (SIERR) and the Italian Society of Human Genetic (SIGU) reviewed the literature on this topic, found a consensus, and produced a list of relevant criteria.

Comparison of euploidy rates of blastocysts in women treated with progestins or GnRH antagonist to prevent the luteinizing hormone surge during ovarian stimulation.

STUDY QUESTION: Does the prevalence of euploid blastocysts differ between patients treated with progestin primed ovarian stimulation (PPOS) and those treated with conventional ovarian stimulation? SUMMARY ANSWER: The numbers of blastocysts and euploid blastocysts per patient and the number of euploid embryos per injected oocyte are similar for patients undergoing progestin-primed ovarian stimulation and for those undergoing conventional ovarian stimulation with GnRH antagonist. WHAT IS KNOWN ALREADY: New approaches to ovarian stimulation have been developed based on the use of drugs administrable by mouth instead of via injections. Attention has been dedicated to progestins to block the LH surge. Previous data regarding the number of oocytes retrieved and the number of good-quality embryos generated in PPOS have demonstrated similar outcomes when compared to conventional ovarian stimulation, even if some concerns regarding the quality of embryos have been advanced. STUDY DESIGN, SIZE, DURATION: This is a prospective non-inferiority age-matched case-control study. In a period of 6 months, a total of 785 blastocysts from 1867 injected oocytes obtained from 192 patients were available for analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Infertile women undergoing IVF and preimplanation genetic testing (PGT) cycles were included. Forty-eight patients were treated with PPOS, and for each of them three age-matched historical controls (n = 144) treated with a GnRH antagonist protocol were selected. PGT was performed according to next-generation sequencing technology. MAIN RESULTS AND THE ROLE OF CHANCE: Basal characteristics were similar in the two groups; a substantial similarity of the main outcome measures in the two treatment groups has also been found. The rate of formation of euploid blastocysts per oocyte was 21% in both the two treatment groups. The percentage of patients with euploid embryos and the total number of euploid blastocysts per patient (median and interquartile range, IQR) in the PPOS group were 38.7 (25.5-52.9) and 2 (1.3-3.1), respectively. These figures were not significantly different in women treated with the GnRH antagonist protocol i.e. 42 (28-53.8) and 2.1 (1.3-2.9), respectively. LIMITATIONS, REASONS FOR CAUTION: This was a case-control study which may limit the reliability of the main findings. WIDER IMPLICATIONS OF THE FINDINGS: Our results encourage the use of PPOS, especially for oocyte donation, for fertility preservation and for patients in which total freezing of embryos is foreseen, for those expected to be high responders or candidates for preimplantation genetic testing. However, studies aiming to investigate the effect of PPOS on the live birth rate are warranted. STUDY FUNDING/COMPETING INTEREST(S): None.

Preimplantation Genetic Testing: Where We Are Today.

BACKGROUND: Preimplantation genetic testing (PGT) is widely used today in in-vitro fertilization (IVF) centers over the world for selecting euploid embryos for transfer and to improve clinical outcomes in terms of embryo implantation, clinical pregnancy, and live birth rates. METHODS: We report the current knowledge concerning these procedures and the results from different clinical indications in which PGT is commonly applied. RESULTS: This paper illustrates different molecular techniques used for this purpose and the clinical significance of the different oocyte and embryo stage (polar bodies, cleavage embryo, and blastocyst) at which it is possible to perform sampling biopsies for PGT. Finally, genetic origin and clinical significance of embryo mosaicism are illustrated. CONCLUSIONS: The preimplantation genetic testing is a valid technique to evaluated embryo euploidy and mosaicism before transfer.

How 1 h of abstinence improves sperm quality and increases embryo euploidy rate after PGT-A: a study on 106 sibling biopsied blastocysts.

PURPOSE: The aim of our study was to evaluate the influence of different ejaculatory abstinence time frames (several days versus 1 h) on semen parameters, blastocysts ploidy rate, and clinical results in assisted reproduction cycles on sibling oocytes. METHODS: This is a prospective study including 22 preimplantation genetic testing for aneuploidy (PGT-A) cycles performed between November 2015 and December 2018. Male partners with oligoastenoteratozoospermia produced two semen samples on the day of oocyte retrieval: the first one after several days of abstinence and the second, 1 h after the first one. Oocytes from each patient were divided into two groups: those in group 1 were injected with spermatozoa from the first ejaculate (N = 121) and oocytes in group 2 with spermatozoa from the second one (N = 144). Outcomes of aniline blue test, fertilization, blastocyst formation, ploidy rates, and clinical results were compared between the two groups. RESULTS: Semen volume resulted lower in the second sperm retrieval. Sperm concentration, motility, and morphology were similar in the two groups. A total of 106 blasotcysts were biospied. Higher blastocyst euploidy rates resulted in group 2 (43.6%) than in group 1 (27.5%). A higher percentage of mature chromatine was observed in group 2. CONCLUSION: Using spermatozoa from samples with a shorter abstinence could be a simple method to select higher quality spermatozoa, reducing aneuploidy rate in blastocysts. Prospective randomized controlled trials should be performed to confirm the potential advantage of using semen samples with short abstinence period to improve the outcome of assisted reproduction cycles.

The aging male: Relationship between male age, sperm quality and sperm DNA damage in an unselected population of 3124 men attending the fertility centre for the first time.

OBJECTIVE: the aim of our study was to put forward insights to treat any possible correlation among sperm quality, sperm DNA damage and male age as they may have fertility implications for men who choose to delay fatherhood. MATERIALS AND METHODS: Our study is a non-interventional retrospective analysis of 3124 semen samples from patients that were investigated for the conventional semen parameters. Tunel test assay was set up for the evaluation of the sperm DNA fragmentation index (DFI). We applied the Kappa index to compare both the 1999 and the 2010 World Health Organization (WHO) reference criteria to evaluate the competence of such semen parameters categorization during the standard routine of our laboratory. RESULTS: With regards to our findings, it is possible to underline a significant relationship between aging and semen volume (p = 0.001), motility (p = 0.009), semen viscosity (p < 0.003) and sperm DNA damage (p < 0.009). We found a trend when focusing on the semen concentration (p = 0.05). The analysis of sperm morphology did not show any influence with advancing age (p = 0.606). When comparing both the 1999 and the 2010 WHO scales we found no accordance in the appraisal of sperm morphology but a very good one in the evaluation of the other parameters. CONCLUSIONS: Conventional semen analysis represents the opportunity to draw up a proxy insight on the male fertility status even if semen quality can only indirectly assess the probability of pregnancy. Several studies have verified a decay in the male reproductive system, sperm quality and fertility with advancing age although the reported results are not yet conclusive. Our results substantially agree with those findings outlined in the literature. Moreover we find that the discrepancy between the two WHO reference scales would eventually lead to an improper diagnosis of infertility.

Testicular histopathology, semen analysis and FSH, predictive value of sperm retrieval: supportive counseling in case of reoperation after testicular sperm extraction (TESE).

BACKGROUND: To provide indicators for the likelihood of sperm retrieval in patients undergoing testicular sperm extraction is a major issue in the management of male infertility by TESE. The aim of our study was to determine the impact of different parameters, including testicular histopathology, on sperm retrieval in case of reoperation in patients undergoing testicular sperm extraction. METHODS: We retrospectively analyzed 486 patients who underwent sperm extraction for intracytoplasmic sperm injection and testicular biopsy. Histology was classified into: normal spermatogenesis; hypospermatogenesis (reduction in the number of normal spermatogenetic cells); maturation arrest (absence of the later stages of spermatogenesis); and Sertoli cell only (absence of germ cells). Semen analysis and serum FSH, LH and testosterone were measured. RESULTS: Four hundred thirty patients had non obstructive azoospermia, 53 severe oligozoospermia and 3 necrozoospermia. There were 307 (63%) successful sperm retrieval. Higher testicular volume, lower levels of FSH, and better histological features were predictive for sperm retrieval. The same parameters and younger age were predictive factors for shorter time for sperm recovery. After multivariable analysis, younger age, better semen parameters, better histological features and lower values of FSH remained predictive for shorter time for sperm retrieval while better semen and histology remained predictive factors for successful sperm retrieval. The predictive capacity of a score obtained by summing the points assigned for selected predictors (1 point for Sertoli cell only, 0.33 points for azoospermia, 0.004 points for each FSH mIU/ml) gave an area under the ROC curve of 0.843. CONCLUSIONS: This model can help the practitioner with counseling infertile men by reliably predicting the chance of obtaining spermatozoa with testicular sperm extraction when a repeat attempt is planned.

Influence of human sperm origin, testicular or ejaculated, on embryo morphokinetic development.

In this retrospective observational study (October 2014 - July 2016), the impact of sperm origin on embryo morphokinetics and on clinical outcomes after intracytoplasmic sperm injection was evaluated. The developmental kinetics of embryos obtained either with testicular sperm (40 cycles; testicular sperm group) or with thawed donor sperm (26 cycles; donor sperm group) was analysed up to day-3 of culture with a time-lapse incubation system. In the testicular sperm group, all patients were affected by nonobstructive azoospermia. The timing of second polar body extrusion (IIPB), and the time to reach the 4-cells (t4) and 9-cells (t9) stages, differed significantly between the two groups: the IIPB extrusion and t4 were anticipated, whereas t9 was retarded in the testicular sperm group. We hypothesise that a different sperm maturation grade may influence the timing of embryo development: an early paternal effect of testicular sperm could be manifested as an anticipation in the IIPB extrusion and in the time for reaching the 4-cells stage. Conversely, a later paternal effect could be visible as a retardation in the timing at which the embryo reaches the 9-cells stage. Interestingly, clinical outcomes did not differ between the two groups except the implantation rate which was significantly increased in the donor sperm group.

HCG administration after endogenous LH rise negatively influences pregnancy rate in modified natural cycle for frozen-thawed euploid blastocyst transfer: a pilot study.

PURPOSE: The aim of the present study was to evaluate whether in a modified natural cycle (modified-NC) for a frozen-thawed single euploid blastocyst transfer, a critical LH value, above which human chorionic gonadotropin (hCG) administration should be avoided, may be defined. METHODS: One hundred and sixty-seven patients underwent modified natural cycle in order to transfer a single frozen-thawed euploid blastocyst. All embryos were obtained by intracytoplasmic sperm injection and were biopsied at the blastocyst stage and analyzed by means of array comparative genomic hybridization (aCGH). Ovulation was induced using 10.000 IU hCG when the mean follicle diameter was at least of 17 mm, independently from LH values. The primary end points were the hCG-positive test and clinical pregnancy. The interim analysis showed that LH value ≥ 13 mIU/ml on the day of hCG injection may negatively influence the clinical results, suggesting that in this condition, it should be advisable waiting for spontaneous ovulation. RESULTS: Among patients who received hCG for ovulation induction, the hCG-positive test and clinical pregnancy rates in modified-NC were significantly lower in cycles with LH ≥ 13 mIU/ml in respect to those with LH < 13 mIU/ml (45.4 vs 73.3 and 36.4 vs 65.9%, in LH ≥ 13 and LH < 13 groups, respectively). In patients with LH value ≥ 13 mIU/ml, hCG administration led to significantly lower rates of hCG-positive test (45.4 vs 74.5% in hCG administration and spontaneous ovulation groups, respectively) and clinical pregnancy (36.4 vs 64.7% in hCG administration and spontaneous ovulation groups, respectively). The baseline patient characteristics were comparable in all groups. CONCLUSIONS: The findings of this study highlight that LH elevation ≥ 13 mIU/ml prior to hCG administration may negatively affect clinical pregnancy rates in modified-NC for single euploid blastocyst transfer. The LH determination should be routinely performed during follicular monitoring. In the presence of LH level ≥ 13 mIU/ml, hCG administration should be avoided, and the embryo transfer should be planned only after spontaneous follicular rupture.

Genetic diseases and aneuploidies can be detected with a single blastocyst biopsy: a successful clinical approach.

STUDY QUESTION: Can simultaneous detection of aneuploidies and genetic diseases or chromosomal aberrations in blastocysts reduce the chance of transferring embryos with low implantation potential, guaranteeing good clinical outcomes? SUMMARY ANSWER: The screening for chromosomal aneuploidies revealed that 50.6% of blastocysts diagnosed free of genetic disease or balanced, were aneuploid, therefore avoiding the transfer of blastocysts potentially resulting in implantation failures, miscarriages, or in some cases, in health affected live births. WHAT IS KNOWN ALREADY: PGD is applied in patients at risk of transmitting genetically inheritable diseases to their offspring. It has been demonstrated that aneuploidies can involve chromosomes other than those investigated with PGD, affecting embryo implantation competence. Performing the biopsy at blastocyst level produces higher clinical outcomes allowing a more accurate diagnosis, compared to blastomere biopsy. STUDY DESIGN, SIZE, DURATION: This consecutive case series study was performed from October 2011 to May 2016. Clinical and biological outcomes from 1122 blastocysts obtained in 304 PGD cycles for monogenic diseases (N = 163) or chromosomal rearrangements (N = 141) were analyzed. When the blastocyst resulted transferable after the PGD analysis or chromosomal rearrangement analysis, its ploidy status by mean of preimplantation genetic screening (PGS) was also detected using the same biopsy sample. Mean female age was 35.4 ± 4.2 years old. All biopsies were performed at blastocyst stage and analyzed by Whole Genome Amplification (WGA) followed by PCR for monogenic diseases, and by array-comparative genotype hybridization (array-CGH) for all cycles. PARTICIPANTS/MATERIALS, SETTING, METHOD: All mature oocytes retrieved were injected and cultured individually until the blastocyst stage at 37°C, 6% CO2, 5% O2. When the blastocyst was formed, it was biopsied and vitrified, awaiting the genetic results. The frozen-thawed embryo transfer was performed in a subsequent cycle. In some cases, when the blastocyst was obtained within the morning of Day 5 of culture, it had been maintained in culture and transferred on Day 6, after receiving the genetic report. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 2809 (2718 fresh and 91 frozen-thawed) mature oocytes were injected with a fertilization rate of 75.5% (N = 2120), leading to the development of 2102 embryos. A further 24 frozen embryos, previously vitrified without any genetic testing, were successfully warmed for genetic screening. A total of 2126 embryos were cultured with a blastocyst formation rate of 52.8% (N = 1122); all of them were biopsied from Day 4 to Day 7 of culture. After the genetic analysis, 309 (27.5%) blastocysts resulted transferable, both for monogenic disease or translocation and for their ploidy status, 42 were diploid/aneuploid mosaic, 55 were no result and 716 were not transferable, due to genetic disease or chromosomal rearrangement and/or for their ploidy status. Of note, 316 (50.6% of transferable blastocysts after PGD and 28.2% of total number of biopsied blastocysts) of the blastocysts resulted healthy for the genetic disease or chromosomal rearrangement were aneuploid. Out of 304 PGD/PGS cycles performed, 28.6% (N = 87) resulted in no-transferable blastocysts after only PGD analysis; this percentage increased to 39.8% (N = 121) when also PGS was carried out (Mc Nemar test P < 0.001). A total of 202 embryo-transfers were performed, 53 fresh and 149 cryopreserved, in which 218 healthy or carrier euploid blastocysts were transferred. Clinical pregnancy, implantation and miscarriage rates were 49.0, 47.7 and 9.9%, respectively. To date, 66 deliveries occurred with 70 healthy babies born and 13 pregnancies are still ongoing. Finally, 91 euploid healthy blastocysts are still cryopreserved waiting to be transferred. LIMITATIONS, REASONS FOR CAUTION: A higher than expected cycle cancellation rate could be found due to the double genetic analysis performed. For this reason, particular care should be taken in drafting and explaining informed consent, in order to avoid patient drop out. WIDER IMPLICATIONS OF THE FINDINGS: When the biopsy has to be performed in order to prevent the transmission of an inheritable disease, it should be mandatory to analyze also the genetic status of the blastocyst, avoiding useless embryo-transfers in this particular category of patients. In our study, 316 aneuploid healthy blastocysts could have been transferred without performing PGS, leading to implantation failures, miscarriages, or in some cases, to live births affected by different syndromes. STUDY FUNDING/COMPETING INTEREST(S): No specific funding was obtained for this study. None of the authors have any competing interests to declare. TRIAL REGISTRATION NUMBER: Not applicable.

Correlation between aneuploidy, standard morphology evaluation and morphokinetic development in 1730 biopsied blastocysts: a consecutive case series study.

STUDY QUESTION: Are there correlations among human blastocyst ploidy status, standard morphology evaluation and time-lapse kinetics? SUMMARY ANSWER: Correlations were observed, in that euploid human blastocysts showed a higher percentage with top quality inner cell mass (ICM) and trophectoderm (TE), higher expansion grades and shorter time to start of blastulation, expansion and hatching, compared to aneuploid ones. WHAT IS KNOWN ALREADY: Embryo quality has always been considered an important predictor of successful implantation and pregnancy. Nevertheless, knowledge of the relative impact of each morphological parameter at the blastocyst stage needs to be increased. Recently, with the introduction of time-lapse technology, morphokinetic parameters can also be evaluated. However, a large number of studies has reported conflicting outcomes. STUDY DESIGN, SIZE, DURATION: This was a consecutive case series study. The morphology of 1730 blastocysts obtained in 530 PGS cycles performed from September 2012 to April 2014 that underwent TE biopsy and array comparative genomic hybridization was analyzed retrospectively. A total of 928 blastocysts were cultured in a time-lapse incubator allowing morphokinetic parameters to be analyzed. PARTCIPANTS/MATERIALS, SETTING, METHOD: Mean female age was 36.8 ± 4.24 years. Four hunderd fifty-four couples were enrolled in the study: 384, 64 and 6 of them performed single, double or triple PGS cycles, respectively. In standard morphology evaluation, the expansion grade, and quality of the ICM and TE were analyzed. The morphokinetic parameters observed were second polar body extrusion, appearance of two pronuclei, pronuclear fading, onset of two- to eight-cell divisions, time between the two- and three-cell (cc2) and three- and four-cell (s2) stages, morulae formation time, starting blastulation, full blastocyst stage, expansion and hatching timing. MAIN RESULTS AND THE ROLE OF CHANCE: Of the 1730 biopsied blastocysts, 603 were euploid and 1127 aneuploid. We observed that 47.2% of euploid and 32.8% of aneuploid blastocysts showed top quality ICM (P < 0.001), and 17.1% of euploid and 28.5% of aneuploid blastocysts showed poor quality ICM (P < 0.001). Top quality TE was present in 46.5% of euploid and 31.1% of aneuploid blastocysts (P < 0.001), while 26.6% of euploid and 38.1% of aneuploid blastocysts showed poor quality TE (P < 0.001). Regarding expansion grade, 81.1% of euploid and 72.4% of aneuploid blastocysts were fully expanded (Grade 5-6; P < 0.001). The timing of cleavage from the three- to four-cell stage, of reaching four-cell stage, of starting blastulation, reaching full blastocyst stage, blastocyst expansion and hatching were 2.6 (95% confidence interval (CI): 1.7-3.5), 40.0 (95% CI: 39.3-40.6), 103.4 (95% CI: 102.2-104.6), 110.2 (95% CI: 108.8-111.5), 118.7 (95% CI: 117.0-120.5) and 133.2 (95% CI: 131.2-135.2) hours in euploid blastocysts, and 4.2 (95% CI: 3.6-4.8), 41.1 (95% CI: 40.6-41.6), 105.0 (95% CI: 104.0-106.0), 112.8 (95% CI: 111.7-113.9), 122.1 (95% CI: 120.7-123.4) and 137.4 (95% CI: 135.7-139.1) hours in aneuploid blastocysts (P < 0.05 for early and P < 0.0001 for later stages of development), respectively. No statistically significant differences were found between euploid and aneuploid blastocysts for the remaining morphokinetic parameters.A total of 407 embryo transfers were performed (155 fresh, 252 frozen-thawed blastocysts). Higher clinical pregnancy, implantation and live birth rates were obtained in frozen-thawed compared to fresh embryo transfers (P = 0.0104, 0.0091 and 0.0148, respectively). The miscarriage rate was 16.1% and 19.6% in cryopreserved and fresh embryo transfer, respectively. The mean female age was lower in the euploid compared to aneuploid groups (35.0 ± 3.78 versus 36.7 ± 4.13 years, respectively), We found an increasing probability for aneuploidy with female age of 10% per year (odds ratio (OR) = 1.1, 95% CI: 1.1-1.2, P < 0.001). LIMITATIONS, REASONS FOR CAUTION: The main limitation of morphology assessment is that it is a static system and can be operator-dependent. In this study, eight embryologists performed morphology assessments. The main limitation of the time-lapse technology is that it is impossible to rotate the embryos making it very difficult to observe them in case of blastomere overlapping or increased cytoplasmic fragmentation. WIDER IMPLICATIONS OF THE FINDINGS: Although there seems to be a relationship between the ploidy status and blastocyst morphology/development dynamics, the evaluation of morphological and morphokinetic parameters cannot currently be improved upon, and therefore replace, PGS. Our results on ongoing pregnancy and miscarriage rates suggest that embryo evaluation by PGS or time-lapse imaging may not improve IVF outcome. However, time-lapse monitoring could be used in conjunction with PGS to choose, within a cohort, the blastocysts to analyze or, when more than one euploid blastocyst is available, to select which one should be transferred. STUDY FUNDING/COMPETING INTERESTS: No specific funding was obtained for this study. None of the authors have any competing interests to declare.

A novel stepwise micro-TESE approach in non obstructive azoospermia.

BACKGROUND: The purpose of the study was to investigate whether micro-TESE can improve sperm retrieval rate (SRR) compared to conventional single TESE biopsy on the same testicle or to contralateral multiple TESE, by employing a novel stepwise micro-TESE approach in a population of poor prognosis patients with non-obstructive azoospermia (NOA). METHODS: Sixty-four poor prognosis NOA men undergoing surgical testicular sperm retrieval for ICSI, from March 2007 to April 2013, were included in this study. Patients inclusion criteria were a) previous unsuccessful TESE, b) unfavorable histology (SCOS, MA, sclerahyalinosis), c) Klinefelter syndrome. We employed a stepwise micro-TESE consisting three-steps: 1) single conventional TESE biopsy; 2) micro-TESE on the same testis; 3) contralateral multiple TESE. RESULTS: SRR was 28.1 % (18/64). Sperm was obtained in both the initial single conventional TESE and in the following micro-TESE. The positive or negative sperm retrieval was further confirmed by a contralateral multiple TESE, when performed. No significant pre-operative predictors of sperm retrieval, including patients' age, previous negative TESE or serological markers (LH, FSH, inhibin B), were observed at univariate or multivariate analysis. Micro-TESE (step 2) did not improve sperm retrieval as compared to single TESE biopsy on the same testicle (step 1) or multiple contralateral TESE (step 3). CONCLUSIONS: Stepwise micro-TESE could represent an optimal approach for sperm retrieval in NOA men. In our view, it should be offered to NOA patients in order to gradually increase surgical invasiveness, when necessary. Stepwise micro-TESE might also reduce the costs, time and efforts involved in surgery.

The endometrial preparation for frozen-thawed euploid blastocyst transfer: a prospective randomized trial comparing clinical results from natural modified cycle and exogenous hormone stimulation with GnRH agonist.

PURPOSE: The aim of the study was to evaluate two methods of endometrial preparation for frozen-thawed single euploid blastocyst transfer: modified natural and artificial cycle with GnRH-agonist pituitary suppression. METHODS: In this prospective, controlled randomized trial, a total of 236 patients undergoing infertility treatment were randomized in 1:1 ratio; 118 received a frozen-thawed single euploid blastocyst transfer in a modified natural cycle and 118 in an artificial cycle with GnRH-agonist pituitary suppression. In the artificial protocol, GnRH-agonist combined with estradiol valerate was administered. In the natural protocol, only final oocyte maturation was induced using human chorionic gonadotropin administration. The primary end-points were the clinical pregnancy and implantation rates; the secondary end-points were the cost-benefit in terms of drug cost and the number of visits and the woman psychological distress caused by the treatment. RESULTS: No significant differences were found in clinical pregnancy, implantation, and miscarriage rates between protocols. The number of clinical and ultrasound controls and the number of laboratory dosages and venous samplings were similar in both study groups. No significant differences were found between the groups in the anxiety and depression values before the start of treatment, on the days of progesterone administration, the blastocyst transfer, and pregnancy test. CONCLUSIONS: The findings of this study evidence that in case of frozen-thawed single euploid blastocyst transfer, both protocols are equally effective in terms of clinical outcomes, cost-benefit, and patient compliance. The choice of endometrial preparation protocol should be based on women menstrual and ovulatory characteristics or otherwise on patient need for cycle planning. TRIAL REGISTRATION: www.clinicaltrials.gov with number NCT02378584.

Analysis of MYO-Inositol effect on spermatozoa motility, in hyper viscous ejaculates and in patients with grades II and III varicocele.

The goal of this study is to evaluate MYOInositol effects on spermatozoa motility, in patients' ejaculates with severe varicocele or hyper viscosity. The study included normal viscosity ejaculate from 30 patients affected by varicocele and hyper viscosity ejaculate from 33 patients without any testicular pathologies. All selected samples showed sperm concentration > 2 million/ml and progressive motility < 32%. In both groups, the pellet obtained after centrifugation in buffered medium, was divided in two aliquots, both incubated for 15 minutes at 37°C: one with MYO-Inositol and the other one, as control, only in phosphate buffered saline (PBS). Afterwards, the sperm progressive motility was assessed using Computer Assisted Sperm Analysis (CASA system). Incubation with MYO-Inositol improved sperm progressive motility in high viscosity samples compared to control group (38.9% ± 3.0 vs 24.35% ± 2.41, respectively; p ≤ 0.0001). Conversely, no statistically significant difference was observed in total sperm progressive motility in varicocele samples compared with control group (22.7% ± 2.07 vs 26.7% ± 3.31, respectively; p = 0.085). The MYO-Inositol positive effect on spermatozoa motility may depend on the type of sperm damage: heavy structural and biochemical defects which typically affects patients with varicocele are not restored by Inositol. On the contrary, MYOInositol is able to improve sperm motility in semen samples with high viscosity, since those samples show no substantial structural sperm defects.

Improved blastocyst formation with reduced culture volume: comparison of three different culture conditions on 1128 sibling human zygotes.

PURPOSE: The aim of the present randomized, comparative study was to evaluate the effect of reduced culture volumes on sibling human embryo development. METHODS: Firstly, sibling injected oocytes obtained from 88 out of 165 consenting couples undergoing infertility treatment were cultured either in large (35 µl) or in small drops (15 µl) of culture medium. Secondly, sibling injected oocytes from 77 couples were cultured either in large (35 µl) or in mini drops (7 µl). Embryo quality on day-2 and day-3 and blastocyst formation rate on day-5 were evaluated. RESULTS: No statistically significant difference in terms of embryo quality was detected comparing embryos cultured either in large (35 µl) or small (15 µl) drops until blastocyst stage. Similarly, no difference appeared between large (35 µl) or mini (7 µl) drops until day-3, however a significantly higher blastocyst formation rate was observed in mini (7 µl) drops on day-5. CONCLUSIONS: Reduced culture volume seems not to influence early embryo development but a reduction of medium appears to positively affect blastocyst development. This supports the hypothesis that the pre-implantation embryo produces autocrine factors which exert a positive effect on embryo development when culture is performed in a reduced volume.

Application of next-generation sequencing technology for comprehensive aneuploidy screening of blastocysts in clinical preimplantation genetic screening cycles.

STUDY QUESTION: Can next-generation sequencing (NGS) techniques be used reliably for comprehensive aneuploidy screening of human embryos from patients undergoing IVF treatments, with the purpose of identifying and selecting chromosomally normal embryos for transfer? SUMMARY ANSWER: Extensive application of NGS in clinical preimplantation genetic screening (PGS) cycles demonstrates that this methodology is reliable, allowing identification and transfer of euploid embryos resulting in ongoing pregnancies. WHAT IS KNOWN ALREADY: The effectiveness of PGS is dependent upon the biology of the early embryo and the limitations of the technology. Fluorescence in situ hybridization, used to test for a few chromosomes, has largely been superseded by microarray techniques that test all 24 chromosomes. Array comparative genomic hybridization (array-CGH) has been demonstrated to be an accurate PGS method and has become the de facto gold standard, but new techniques, such as NGS, continue to emerge. STUDY DESIGN, SIZE, DURATION: The study consisted of a prospective trial involving a double blind parallel evaluation, with both NGS and array-CGH techniques, of 192 blastocysts obtained from 55 consecutive clinical PGS cycles undertaken during the period of September to October 2013. Consistency of NGS-based aneuploidy detection was assessed by matching the results obtained with array-CGH-based diagnoses. Primary outcome measure was accuracy of the chromosomal analysis; secondary outcome measures were clinical outcomes. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: Fifty-five patients (median age 39.3 years, range 32-46) undergoing PGS were enrolled in the study. All embryos were cultured to blastocyst stage; trophectoderm biopsy was performed on Day 5 of development or Day 6/7 for slower growing embryos. The method involved whole genome amplification followed by both NGS and array-CGH. The MiSeq control software, real-time analysis and reporter performed on-board primary and secondary bioinformatics analysis. Copy number variation analysis was accomplished with BlueFuse Multi software. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 192 blastocysts were blindly evaluated with the NGS-based protocol. Paired comparison between NGS and array-CGH from individual embryos showed concordant results in 191/192 (99.5%) of the blastocysts tested. In total 4608 chromosomes were assessed, 211 (4.6%) of which carried a copy number imbalance. NGS specificity for aneuploidy calling (consistency of chromosome copy number assignment) was 99.98% (4333/4334; 95% confidence interval [95% CI]: 99.87-100) with a sensitivity of 100% (211/211, 95% CI: 99.25-100). Despite one discordant result, NGS specificity and sensitivity for aneuploid embryo calling (24-chromosome diagnosis consistency) were both 100% since the discordant sample presented several other aneuploidies. Clinical application of the NGS-based approach revealed 74/192 (38.5%) euploid blastocysts. Following transfer of 50 embryos in 47 women, 34 women had positive hCG levels: 30 pregnancies continued, confirmed by at least one fetal sac and heart beat (63.8% clinical pregnancy rate/embryo transfer), 3 were biochemical and 1 miscarried. A total of 32 embryos implanted and led to the presence of a fetal sac (64.0% implantation rate). All pregnancies went to term resulting in the birth of 31 healthy babies. LIMITATION, REASON FOR CAUTION: Although clinical results reported high pregnancy outcomes following transfer of screened embryos, further data and broad-based clinical application are required to better define the role of NGS in PGS. Before recommending widespread application, a randomized controlled trial confirming its clinical effectiveness is advisable. WIDER IMPLICATION OF THE FINDING: This is the first study reporting extensive application of NGS-based comprehensive aneuploidy screening on embryos at blastocyst stage in a clinical setting versus array-CGH as test of reference. NGS has demonstrated a reliable methodology, with the potential to improve chromosomal diagnosis on embryos especially in terms of high-throughput, automation and ability to detect aneuploidy. NGS methodology may represent a valuable alternative to the other comprehensive aneuploidy screening techniques currently available. STUDY FUNDING/COMPETING INTERESTS: No external funding was sought for this study. Drs F.K. and C.-E.M. are full-time employees of Illumina, Inc., which provided NGS library and sequencing reagents for the study. All other authors have no conflicts to declare. TRIAL REGISTRATION NUMBER: Not applicable.

Traditional intracytoplasmic sperm injection provides equivalent outcomes compared with human zona pellucida-bound selected sperm injection.

The capability of human zona pellucida (ZP) to bind selectively to normal functional sperm with normal chromatin has been reported widely in the literature. The aim of this study was to evaluate whether ZP-binding sperm selection may represent a method to retrieve superior spermatozoa for intracytoplasmic sperm injection (ICSI). Patients were divided into two groups: a ZP-ICSI and a conventional ICSI group. In the ZP-ICSI group, spermatozoa for injection were selected after ZP-sperm incubation and spermatozoa that were tightly bound to the ZP were used for ICSI (ZP-ICSI). Clinical outcomes of ZP-ICSI were compared with the outcomes of traditional scientist-selected sperm injection (conventional ICSI). Results did not show any significant difference in fertilization, pregnancy, implantation and take-home-baby rates between conventional ICSI and ZP-ICSI. However, when data relative to patients who received ZP-ICSI were analyzed, an interesting result was observed: higher sperm concentration and morphology correlated with higher ZP-sperm binding. Additionally, patients with higher ZP-sperm binding seem to have improved pregnancy and take-home-baby rates. In conclusion, this study shows that ZP-ICSI is not a superior method compared with conventional ICSI. However, clinical ICSI outcomes were apparently improved in the presence of good ZP-sperm binding. We therefore speculate that sperm competence to ICSI could be reduced when the sperm's ability to bind the ZP is impaired.