Allele-Specific Chromosome Removal after Cas9 Cleavage in Human Embryos.

Correction of disease-causing mutations in human embryos holds the potential to reduce the burden of inherited genetic disorders and improve fertility treatments for couples with disease-causing mutations in lieu of embryo selection. Here, we evaluate repair outcomes of a Cas9-induced double-strand break (DSB) introduced on the paternal chromosome at the EYS locus, which carries a frameshift mutation causing blindness. We show that the most common repair outcome is microhomology-mediated end joining, which occurs during the first cell cycle in the zygote, leading to embryos with non-mosaic restoration of the reading frame. Notably, about half of the breaks remain unrepaired, resulting in an undetectable paternal allele and, after mitosis, loss of one or both chromosomal arms. Correspondingly, Cas9 off-target cleavage results in chromosomal losses and hemizygous indels because of cleavage of both alleles. These results demonstrate the ability to manipulate chromosome content and reveal significant challenges for mutation correction in human embryos.

Identifying parental and cell-division origins of aneuploidy in the human blastocyst.

Preimplantation genetic testing commonly employs simplistic copy-number analyses to screen for aneuploidy in blastocyst trophectoderm biopsies. Interpreting intermediate copy number alone as evidence of mosaicism has led to suboptimal estimation of its prevalence. Because mosaicism originates from mitotic nondisjunction, utilizing SNP microarray technology to identify the cell-division origins of aneuploidy might provide a more accurate estimation of its prevalence. The present study develops and validates a method of determining the cell-division origin of aneuploidy in the human blastocyst by using both genotyping and copy-number data in parallel. The concordance of predicted origins with expected results was demonstrated in a series of truth models (99%-100%). This included determination of X chromosome origins from a subset of normal male embryos, determination of the origins of translocation chromosome-related imbalances via embryos from couples with structural rearrangements, and prediction of either mitotic or meiotic origins via multiple rebiopsies of embryos with aneuploidy. In a cohort of blastocysts with parental DNA (n = 2,277), 71% were euploid, 27% were meiotic aneuploid, and 2% were mitotic aneuploid, indicating a low frequency of bona fide mosaicism in the human blastocyst (mean maternal age: 34.4). Chromosome-specific trisomies in the blastocyst were also consistent with observations previously established in products of conception. The ability to accurately identify mitotic-origin aneuploidy in the blastocyst could benefit and better inform individuals whose IVF cycle results in all aneuploid embryos. Clinical trials with this methodology might also help provide a definitive answer regarding the reproductive potential of bona fide mosaic embryos.

Exploring temporal congruence in motor imagery and movement execution in non-specific chronic low back pain.

Chronic non-specific low back pain (NSCLBP) is linked to sensorimotor dysfunctions and altered motor planning, likely due to neuroplastic changes. Motor imagery (MI) and movement execution share neural pathways, but the relationship between imagined and executed movements in NSCLBP patients remains underexplored. This study aimed to assess the temporal congruence between imagined and executed movements in NSCLBP sufferers, with secondary goals of investigating group differences in movement chronometry, psychological well-being, and disability, as well as possible correlations among these factors. Fifty-six participants, including 28 NSCLBP patients and 28 asymptomatic subjects (AS), performed lumbar flexion and Timed Up and Go (TUG) tasks. NSCLBP patients showed significant temporal incongruence in both tasks, executing movements more slowly than imagined, whereas AS displayed incongruence only in the TUG task. NSCLBP patients also took longer to imagine and execute lumbar flexion movements compared to AS, with correlations observed between execution delays, higher disability, and greater fear of movement. The findings highlight a lack of temporal congruence in NSCLBP patients, especially in lumbar flexion, emphasizing the complex relationship between chronic pain, motor ability, and psychological factors. These results suggest that integrated treatment approaches addressing cognitive and emotional aspects are crucial for managing NSCLBP.

High-resolution PGT-A results in incidental identification of patients with small pathogenic copy number variants.

PURPOSE: This study aimed to evaluate whether a high-throughput high-resolution PGT-A method can detect copy number variants (CNVs) that could have clinical implications for patients and their embryos. METHODS: A prospective analysis of PGT-A cases was conducted using a high-resolution SNP microarray platform with over 820,000 probes. Cases where multiple embryos possessed the same segmental imbalance were identified, and preliminary PGT-A reports were issued recommending either parental microarray or conventional karyotyping to identify CNVs or translocations. RESULTS: Analysis of 6080 sequential PGT-A cases led to identification of 41 cases in which incidental findings were observed (0.7%) and parental testing was recommended. All cases, in which parental studies were completed, confirmed the original PGT-A incidental findings. In 2 of the cases, parental studies indicated a pathogenic variant with clinical implications for the associated embryos. In one of these cases, the patient was identified as a carrier of a duplication in chromosome 15q11.2:q11.2 (SNRPN + +), which is associated with autism spectrum disorder. In the second case, the patient was heterozygous positive for an interstitial deletion of 3p26.1:p26.3, which is associated with 3p deletion syndrome and had clinical implications for the patient and associated embryos. In each case, parental studies were concordant with PGT-A findings and revealed the presence of an otherwise unknown CNV. CONCLUSION: High-throughput high-resolution SNP array-based PGT-A has the ability to detect previously unknown and clinically significant parental deletions, duplications, and translocations. The use of cost-effective SNP array-based PGT-A methods may improve the effectiveness of PGT by identifying and preventing previously unknown pathogenic CNVs in children born to patients seeking in vitro fertilization.

Chemical gasification: An alternative approach to in vitro maturation of bovine oocytes.

This study aimed to evaluate the effect of chemical gasification and HEPES as alternative systems to pH control during in vitro maturation on bovine oocytes competence. Groups of 20 bovine cumulus oocytes complexes (COCs) were randomly distributed and cultured for 24 h in one of the following experimental groups: (i) chemical reaction (ChRG) system: CO2 generated from sodium bicarbonate and citric acid reaction (ii) culture media TCM-HEPES (HEPES-G); and (iii) control group (CNTG) in conventional incubator. After in vitro maturation (IVM), the COCs were in vitro fertilized (IVF), and in vitro cultivated (IVC) in a conventional incubator. We evaluated oocyte nuclear maturation, cleavage and blastocyst rates, in addition to the relative mRNA expression of BAX, BMP-15, AREG and EREG genes in oocytes and cumulus cells. The proportion of oocytes in metaphase II was higher in CNTG and ChRG (77.57% and 77.06%) than in the HEPES-G (65.32%; p = .0408 and .0492, respectively). The blastocyst production was similar between CNTG and ChRG (26.20% and 28.47%; p = .4232) and lower (p = .001) in the HEPES-G (18.71%). The relative mRNA expression of BAX gene in cumulus cells was significantly higher (p = .0190) in the HEPES-G compared to the CNTG. Additionally, the relative mRNA expression of BMP-15 gene was lower (p = .03) in oocytes from HEPES-G compared to the CNTG. In conclusion, inadequate atmosphere control has a detrimental effect on oocyte maturation. Yet, the use of chemical gasification can be an efficient alternative to bovine COCs cultivation.

Sensorimotor, cognitive and affective behavior according to perceived level of disability in patients with chronic low back pain: an observational cross-sectional study.

OBJECTIVES: The aim was to evaluate the influence of the level of disability on sensorimotor and psychological variables in nonspecific chronic low back pain (NCLBP). METHODS: A cross-sectional observational study was performed with 90 participants, divided into one group with NCLBP (60 participants) and one asymptomatic group (30 participants). Symptomatic participants were divided into a "major" or "minor" disability group using the Roland Morris Disability Questionnaire score, resulting in two groups of 30 participants. All participants completed a series of self-administered questionnaires and performed sensorimotor tests. RESULTS: There were no statistically significant differences in the sensorimotor variables except in pain intensity, which was greater in the NCLBP group with high lumbar disability. There were statistically significant differences between the symptomatic groups in the degree of self-efficacy, pain catastrophism and kinesiophobia. CONCLUSIONS: Patients with NCLBP and high levels of disability present greater pain intensity and significantly poorer results in psychological variables compared with those with NCLBP and low levels of disability. In contrast, there were no differences for sensorimotor variables between the patients with NCLBP and high levels of disability and those with low levels of disability.

Visual Behaviours of Expert Padel Athletes When Playing on Court: An In Situ Approach with a Portable Eye Tracker.

Eye-tracking research has allowed the characterisation of gaze behaviours in some racket sports (e.g., tennis, badminton), both in controlled laboratory settings and in real-world scenarios. However, there are no studies about visual patterns displayed by athletes in padel. METHOD: The aim of this exploratory case study was to address the visual behaviours of eight young expert padel athletes when playing match games on a padel court. Specifically, their gaze behaviours were examined with an in situ approach while returned trays/smashes, serves, and volleys were performed by their counterparts. Gaze patterns were registered with an SMI Eye Tracking Glasses 2 Wireless. RESULTS: The participants' gaze was mainly focused on the ball-flight trajectory and on the upper body of the opponents because they were the two visual locations with a larger number of fixations and longer fixation time. No differences were found in these variables for each type of visual location when the three return situations were compared, or independently of them. CONCLUSIONS: Padel players displayed a similar gaze behaviour during different representative return situations. This visual pattern was characterised by fixating at the ball and some opponents' upper kinematics (head, shoulders, trunk, and the region of arm-hand-racket) to perform real interceptive actions while playing against them on a padel court.

State of the Art and Future Perspectives of Atmospheric Chemical Sensing Using Unmanned Aerial Vehicles: A Bibliometric Analysis.

In recent years, unmanned aerial vehicles (UAVs) have been increasingly used to monitor and assess air quality. The interest in the application of UAVs in monitoring air pollutants and greenhouse gases is evidenced by the recent emergence of sensors with the most diverse specifications designed for UAVs or even UAVs designed with integrated sensors. The objective of this study was to conduct a comprehensive review based on bibliometrics to identify dynamics and possible trends in scientific production on UAV-based sensors to monitor air quality. A bibliometric analysis was carried out in the VOSViewer software (version 1.6.17) from the Scopus and Web of Science reference databases in the period between 2012 and 2022. The main countries, journals, scientific organizations, researchers and co-citation networks with greater relevance for the study area were highlighted. The literature, in general, has grown rapidly and has attracted enormous attention in the last 5 years, as indicated by the increase in articles after 2017. It was possible to notice the rapid development of sensors, resulting in smaller and lighter devices, with greater sensitivity and capacity for remote work. Overall, this analysis summarizes the evolution of UAV-based sensors and their applications, providing valuable information to researchers and developers of UAV-based sensors to monitor air pollutants.

Spatial variability of soil physical properties in longitudinal profiles.

The spatial variability of physical properties, such as bulk density, penetration resistance and gravimetric moisture, obtained by applying geostatistics in precision agriculture, can effectively indicate the physical behavior of agricultural soils in longitudinal profiles. In this way, the spatial dependence of physical properties in streets of coffee plantations with different lengths was evaluated in the southern Minas Gerais, Brazil. For this purpose, five longitudinal profiles were measured in streets, each one with depths ranging from 0 to 0.60 m, in six layers of 0.10 m, being the database composed of 432 property, 144 by property, submitted to the ordinary kriging geostatistical method in order to obtain spatial variability maps using the R software. They were evaluated by the lower mean cross-validation error of theoretical models fitted by ordinary least squares (OLS), being detected in higher superficial layers, from 0 to 0.30 m, lower bulk density and lower penetration resistance, with variable gravimetric moisture in the length direction of some streets of coffee plantations, being that these properties presented different structures of spatial dependence for each street.

Preimplantation genetic testing for aneuploidy: A review of published blastocyst reanalysis concordance data.

Preimplantation genetic testing for aneuploidy (PGT-A) reduces miscarriage risk, increases the success of IVF, shortens time to pregnancy, and reduces multiple gestation rates without compromising outcomes. The progression of PGT-A has included common application of next-generation sequencing (NGS) from single nucleotide polymorphism microarray, quantitative real-time PCR, and array comparative hybridization platforms of analysis. Additional putative advances in PGT-A capability include classifying embryos as mosaic and predicting the presence of segmental imbalance. A critical component in the process of technical validation of these advancements involves evaluation of concordance between reanalysis results and initial testing results. While many independent studies have investigated the concordance of results obtained from the remaining embryo with the original PGT-A diagnosis, compilation and systematic analysis of published data has not been performed. Here, we review results from 26 primary research articles describing concordance in 1271 human blastocysts from 2260 pairwise comparisons. Results illustrate significantly higher discordance from PGT-A methods which utilize NGS and include prediction of mosaicism or segmental imbalance. These results suggest caution when considering new iterations PGT-A.

[Diagnostic utility of colonoscopy and histological evaluation in the study of patients with chronic diarrhea]. / Utilidad diagnóstica de la colonoscopia y evaluación histológica en el estudio de pacientes con diarrea crónica.

INTRODUCTION: Patients with chronic diarrhea often undergo colonoscopy evaluation, however, the performance of biopsies or ileoscopy remains controversial. OBJECTIVE: To evaluate the usefulness of colonoscopy plus biopsies in the study of patients with chronic diarrhea. MATERIALS AND METHODS: We retrospectively reviewed patients with chronic diarrhea who underwent colonoscopy between 2015 and 2019. Patients with incomplete data, HIV infection, abnormal endoscopic findings, colonoscopy without blind assessment, being on empiric treatment for diarrhea, and poor diagnosis were excluded. preparation. A descriptive analysis of the characteristics of the patients, histopathological findings and comparison of signs and symptoms according to histopathological finding was performed. RESULTS: 535 patients with chronic diarrhea were evaluated, of these, 283 (52.8%) underwent biopsies. In 55.1% (n=156) of the biopsies some final histopathological diagnosis was obtained. Histopathological diagnoses corresponded to ulcerative colitis (n=3), Crohn's disease (n=5), lymphocytic colitis (n=6), collagenous colitis (n=12), eosinophilic colitis (n=13), infectious colitis (n=13), Melanosis coli (n=15), nonspecific colitis (n=57) and other histological changes (n=32). Crohn's disease was only documented in biopsies of the ileum (p<0.001), ulcerative colitis was only diagnosed in biopsies of the sigmoid rectum (p=0.007), infectious colitis in its highest proportion (30.7%) was documented in biopsies of the right colon (p=0.028). CONCLUSION: Colonoscopy and biopsies are useful in the investigation of patients with chronic diarrhea, obtaining a histological diagnosis in 55% of patients. Ileoscopy complemented colonoscopy findings to a lesser extent.

PREIMPLANTATION GENETIC TESTING: Preimplantation genetic testing for polygenic disease risk.

Since its introduction to clinical practice, preimplantation genetic testing (PGT) has become a standard of care for couples at risk of having children with monogenic disease and for chromosomal aneuploidy to improve outcomes for patients with infertility. The primary objective of PGT is to reduce the risk of miscarriage and genetic disease and to improve the success of infertility treatment with the delivery of a healthy child. Until recently, the application of PGT to more common but complex polygenic disease was not possible, as the genetic contribution to polygenic disease has been difficult to determine, and the concept of embryo selection across multiple genetic loci has been difficult to comprehend. Several achievements, including the ability to obtain accurate, genome-wide genotypes of the human embryo and the development of population-level biobanks, have now made PGT for polygenic disease risk applicable in clinical practice. With the rapid advances in embryonic polygenic risk scoring, diverse considerations beyond technical capability have been introduced.

Mitochondrial DNA content is not predictive of reproductive competence in euploid blastocysts.

RESEARCH QUESTION: Does mitochondrial DNA (mtDNA) copy number predict the reproductive potential of euploid human blastocysts? DESIGN: To investigate whether the amount of mtDNA in trophectoderm biopsies correlates with IVF outcome, euploid human blastocysts (n = 615) used in single embryo transfer were analysed. Furthermore, to determine whether mtDNA content is predictive of reproductive outcome within a given cohort, paired sibling embryos (n = 78) transferred in two consecutive cycles carried out in the same patient (in which one cycle failed to result in implantation and the other cycle resulted in sustained implantation) were studied. Targeted amplification followed by quantitative real-time polymerase chain reaction for two mitochondrial loci (16S and MajArc) relative to a multicopy nuclear genome locus (AluYb8) were carried out to determine relative mtDNA copy number. RESULTS: Sustained implantation was not associated with relative mtDNA copy number (P = 0.78), and there was no threshold value above or below which ongoing implantation was more or less likely. No correlation was observed between maternal age and relative mtDNA copy number (P = 0.39). In addition, no association was found between relative mtDNA levels of sibling embryos and ensuing implantation and delivery rates in women who underwent a successful single embryo transfer before or after a failed transfer using embryos derived from the same cohort of oocytes (P = 0.70). CONCLUSIONS: In trophectoderm samples, mitochondrial DNA copy number analysis was not found to be predictive of euploid human embryo reproductive competence. These data do not support the use of mitochondrial DNA copy number in clinical decision making when selecting which embryo to transfer.

Modulation of phosphatidylinositol 3-kinase activity during in vitro oocyte maturation increases the production of bovine blastocysts.

This study aimed to evaluate the effect of regulating phosphatidylinositol 3-kinase (PI3K) activity on the kinetics of oocyte nuclear maturation and the blastocyst rate. To evaluate oocyte viability, nuclear maturation rate and in vitro embryo production, cumulus-oocyte complexes (COCs) were maintained for 0, 10 min, 6 h or 22 h in TCM 199 medium supplemented with 20 nM wortmannin, an inhibitor of PI3K. After each period, COCs were transferred to the same medium without wortmannin and kept under the same conditions until completion of 22 h of in vitro maturation (IVM). To evaluate the effect of time on progression of nuclear maturation, COCs cultivated with 20 nM wortmannin was maintained for 22, 28 or 34 h of IVM. To determine the effect of wortmannin on the activity of maturation-promoting factor (MPF), COCs were kept under IVM conditions in the presence of the inhibitor for 0, 1, 3, 6, or 8 h. Exposure of COCs to wortmannin decreased (P < 0.05) the percentage of oocytes that reached metaphase II (MII) up to 22 h, MPF activity and reduced PI3K activity by 30%. However, after 28 and 34 h, 70% of oocytes reached the MII stage in the presence of inhibitor Moreover, COCs matured in the presence of wortmannin showed an increase (P < 0.05) in the blastocyst rate. These findings suggested that the regulation of the PI3K activity during IVM of bovine COCs interfered with the meiotic progression due to control of MPF activity, positively affecting the blastocyst rate.

Comparative economic analysis of soil sampling methods used in precision agriculture.

Precision agriculture is an alternative for reducing costs. This study evaluated and economically compared three sampling methods used in precision agriculture with respect to the acquisition of inputs and machines and equipment. The sampling methods used were zone management by elevation (ZME), grid sampling (GS) and sampling guided by apparent electrical conductivity of the soil (OS). Soil samples for the ZME were collected after the definition of zones according to the elevations of the plots. The sample mesh was in a georeferenced mesh of 100 x 100 m. The targeted sampling was performed after a ground proximity sensor was used to identify the apparent electrical conductivity of the soil to define the management areas. From the results of the laboratory tests, the application costs were calculated for lime, phosphorus, potassium and nitrogen to allow a comparison between the methods, volumes and costs. This approach considered the costs of depreciation, insurance, interest, operating costs, labor, maintenance and fuel. With this study, it was possible to compare the volumes of the recommended fertilizers and estimate the overall economic cost of using the technology via sensor. Taking the GS as a reference, the ZME presented as the best alternative compared to other methods.

New Frontiers in IVF: mtDNA and autologous germline mitochondrial energy transfer.

Many infertility specialists support the existence of a relationship between the levels of mitochondrial DNA and the quality of the blastocysts. Despite the extensive use of pre-implantation genetic testing for aneuploidy, a significant percentage of euploid embryos do not implant even though the endometrium is normal. Mitochondrial DNA may be used as a new test in evaluating embryonic vitality.Ovarian aging leads to a decrease in the quantity and quality of oocytes and aged oocytes have a reduced number of mitochondria. Mitochondria are the energy factories of the cells and their lacked could leads to lower fertilization rates and poor embryonic development. Various strategies have been tested to increase the mitochondria quantity and thus improve the quality of oocytes used in in vitro fertilization. Results of ovarian rejuvenation techniques such as autologous mitochondrial transplantation have been controversial. In this review, we describe the state of the art concerning the use of mitochondrial DNA and autologous mitochondrial transplantation as new possibilities to increase success in vitro fertilization.

Nitric oxide impacts bovine sperm capacitation in a cGMP-dependent and cGMP-independent manner.

We aimed to elucidate whether NO acts in in vitro sperm capacitation in bovine via cGMP/PKG1 pathway. For this, cryopreserved bovine sperm were capacitated in vitro with 20 µg/ml heparin (Control) plus treatments: 1 mM L-arginine (L-arg, NO precursor), 50 µM Rp-8-Bromo-ß-phenyl-1,N2 -ethenoguanosine-3',5'-cyclic monophosphorothioate (Rp-8-Br-cGMPS, selective inhibitor of the binding site for cGMP in PKG1), 1 mM 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO, NO scavenger), and the combinations of L-arg + RP-8-Br-cGMPS and L-arg + PTIO. Sperm motility and vigour were determined by phase-contrast microscopy, capacitation status by chlortetracycline staining, and the intracellular concentration of cGMP was measured by ELISA. Data were subjected to analysis of variance and means compared with SNK test at 5% probability. Motility and vigour were lower in sperm treated with PTIO when compared to Control and other treatments (p < .05). The L-arg treatment showed the highest percentage of capacitated sperm when compared to the Control and other treatments (Rp-8-Br-cGMPS, L-arg + Rp-8-Br-cGMPS and PTIO) (69.8 ± 3.4%, 51.2 ± 3.0, 51.1 ± 2.1, 51.2 ± 3.0 and 45.5 ± 2.7, respectively) (p < .05). The capacitation ratio (%) was lower in treatments with Rp-8-Br-cGMPS, L-arg + Rp-8-Br-cGMPS and PTIO, respectively (p < .05). Lastly, cGMP concentration (pmol/ml) was lower in PTIO and L-arg + PTIO (1.3 ± 0.3 and 1.6 ± 0.4) and was higher in Rp-8-Br-cGMPS and L-arg + Rp-8-Br-cGMPS (3.7 ± 0.4 and 4.0 ± 0.5) treatments. We showed that during in vitro capacitation of cattle: (a) NO influences sperm motility and vigour; (b) NO is associated with cGMP synthesis through two independent pathways and (c) the cGMP/PKG1 pathway has a partial role in sperm capacitation and does not involve the L-arg/NO.

Exploring Game Dynamics in Padel: Implications for Assessment and Training.

Courel-Ibáñez, J, Sánchez-Alcaraz Martinez, BJ, and Muñoz Marín, D. Exploring game dynamics in padel: implications for assessment and training. J Strength Cond Res 33(7): 1971-1977, 2019-A better understanding of in-game competition demands potentially improved coaching strategy and quality. However, there is very limited information about game patterns in padel, a very modern racket sport born in the 70s. The purpose of this study was therefore to quantify and classify game dynamics during the match in professional padel players through a multivariate decision tree approach including technical, spatial, and effectiveness indicators. The results determined 3 main game styles strongly defined by the court zone (net, middle, and baseline). In addition, particular technical, spatial, and effectiveness indicators were identified in each zone. In net and middle areas (offense) stood the use of volleys and overhead strokes on the center lane to both keep a positional advantage and solve the point. Conversely in the baseline (defense), the use of corner side walls and the domain of lobs showed to be relevant. The high rate of backhand groundstrokes, involving over 4 of 10 actions, is also remarkable. This information may have relevant implications for coaches working in padel by providing a novel hierarchically organization of game dynamics, which helps in designing training and conditioning programs close to real competitive situations.

Conventional versus minimal ovarian stimulation: an intra-patient comparison of ovarian response in poor-responder women according to Bologna Criteria.

RESEARCH QUESTION: Is minimal ovarian stimulation (MOS) as effective as conventional ovarian stimulation (COS) in ovarian response and embryo quality in the same 46 poor-responder patients according to the Bologna criteria? DESIGN: An intra-patient comparison of patients undergoing both protocols. Ovaries were stimulated with either a gonadotrophin-releasing hormone antagonist protocol and a combination of recombinant FSH and highly purified human menotrophin (HP-HMG) daily (COS), or with the use of clomiphene citrate 50 mg daily and 150 IU of HP-HMG or recombinant FSH every other day from simulation day 4 (MOS). RESULTS: After MOS, significantly more good-quality embryos (1.0 ± 1.2 versus 0.3 ± 0.6) (P = 0.002), oocytes (3.2 ± 1.9 versus 2.0 ± 1.8) (P = 0.002), and mature (metaphase II) oocytes (2.6 ± 1.7 versus 1.6 ± 1.7) (P = 0.001) were obtained. In COS cycles, a significantly higher total gonadotrophin dose was needed per good-quality embryo (+2194 IU; 95% CI 618 to 3170). CONCLUSIONS: In poor responder patients, MOS is a good alternative when COS has failed, or even as a first-line treatment. It offered a significantly greater number of good-quality embryos as well as a higher number of oocytes, using significantly lower doses of gonadotrophins per oocyte and embryo obtained.