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OBJECTIVE: To assess the relationship between human blastocyst chromosomal ploidy established by niPGT-A and increasing age. METHODS: This is a prospective multicenter study carried out by ten assisted reproduction centers after their embryologists acquired training and validated their results with the previous use of niPGT-A. A total of 94 couples with indication for niPGT-A due to increase maternal age, male factor, repeated implantation failures, recurrent abortion or because they requested niPGT-A were included in this study. The couples had no karyotype abnormalities. After ICSI, the embryos were cultured until blastocyst stage using one or two step culture systems, single or sequential media respectively, at 37°C in an atmosphere of 6-7% CO2 and 5-20% O2 incubators. On day 3, we re-evaluated cleavage embryos to complete cumulus cells removal. The embryos were then cultured in individual well, with 20µl of medium under oil until they reached blastocyst stage. The blastocysts were vitrified and stored in liquid nitrogen. After that, the spent blastocyst culture medium (20µl) was transferred to a PCR tube and sent for analysis in the genetic laboratory, where it was stored at -80°C until sequencing. A total of 243 samples of spent blastocyst culture medium were collected on the 5th/6th day. Cell-free DNA secreted on culture medium was amplified using NICS Sample Preparation Kit (Yikon Genomics), based on the MALBAC technology. After whole genome amplification, the DNA was measured using a Qubit 2.0 fluorometer and subjected to next generation sequencing (NGS) using Illumina MiSeq® platform. The data were analyzed using the ChromGo® software (Yikon Genomics). RESULTS: The mean age of the patients was 38±4.08 years with an interval of 20-44 years. The euploid was diagnosed in 36.4% (80/220) of cases, aneuploidy in 31.3% (69/220), and mosaicism in 32.3% (71/220; with ≥60% aneuploidy) of blastocysts. Mosaic values ranged from 29.8% to 33.8% in different age groups. Individually, the most frequent chromosomal abnormality was XXY (Klinefelter Syndrome) occurring in 18 cases, followed by chromosome 21 (trisomy/monosomy) in 8 cases. The niPGT-A data showed a ≥60% incidence of aneuploid cells in all cases of chromosomal mosaicism (n=71). CONCLUSION: A high degree of mosaicism with aneuploidy cells was detected, and some hypotheses were suggested for this data (niPGT-A sensitivity in detecting the self-correction of chromosomal abnormalities phenomenon). However, it did not vary remarkably with age. On the other hand, euploidy levels had a negative correlation with age and aneuploidy levels had a positive relationship. This is the first report in the literature to relate chromosomal ploidy in blastocysts using niPGT-A and increasing patient age.

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OBJECTIVE: To evaluate awareness of and attitudes toward preimplantation genetic testing (PGT) for sickle cell disease (SCD) among parents of children with SCD. STUDY DESIGN: Parents of children with SCD were given an educational handbook on PGT before a routine SCD clinic visit. After their clinic visit, parents were asked to complete an anonymous survey. RESULTS: Of 83 patents approached, 67 (81%) completed the survey. Only 16 of the 67 parents (24%) were previously aware of PGT for SCD. After our clinic-based education, 65 of the 67 parents (97%) indicated that it was important or very important for parents of children with SCD to know about PGT. Among parents interested in having more children, 29 of 32 (91%) would personally consider using PGT if covered by insurance. CONCLUSIONS: Parents of children with SCD are generally not aware of PGT. When educated in clinic, parents viewed information on PGT as valuable. Pediatricians and other health care professionals should inform parents of children with SCD about this reproductive option.

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Approximately 50% of the causes of infertility are of genetic origin. The objective of this study was to analyze the role of genetics in human reproduction by reviewing the main genetic causes of infertility and the use of preimplantation genetic testing in Brazil. This literature review comprised articles in English and Portuguese published on databases PubMed, Scielo, and Bireme from 1990 to 2019. Randomized clinical trials and specialized guidelines were given preference whenever possible. Genetic cause can be traced back to up to 20% of the cases of severe azoospermia or oligozoospermia. Subjects with these conditions are good candidates for genetic screening. In women, genetic causes of infertility (fragile X syndrome, X-trisomy, and Turner's syndrome, some of which diagnosed with karyotyping) culminate with premature ovarian failure. Genetic screening helps advise couples of the risk of experiencing early reproductive capacity loss and of the chances of their offspring carrying genetic disorders. In addition to enhancing the prevention of serious diseases in the offspring of couples at increased risk of genetic diseases, preimplantation genetic screening improves the success rates of assisted reproduction procedures by allowing the selection of euploid embryos for transfer. The interface between genetics and human reproduction has gained significant relevance, but discussions are still needed on which procedures are clinically and ethically acceptable and how they should be regulated.

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BACKGROUND: At our facilities, patients that received embryos using donor oocyte during in vitro fertilization (IVF), usually have had at least one failed attempt to produce at least one euploid embryo with their own oocytes; however, the current debate between using donor over patient oocytes remains inconclusive. We examined the aneuploidy rate and IVF clinical outcomes from embryos derived from either donor or patient oocytes. METHODS: Retrospectively, 973 cycles were examined of patients who underwent a standard IVF protocol. Chromosomal content was determined using Pre-implantation Genetic Testing (PGT) by either microarray-comparative genomic hybridization or Next-generation sequencing from either Day 3 (blastocysts) or Day 5 (trophectoderm) embryo biopsies, respectively. Embryo implantation was confirmed by serum ß-hCG (> 10 m IU/mL/Day 14), whereas clinical pregnancy by a fetal heartbeat (Week 6.5-8). RESULTS: Embryos derived from donor oocytes presented with more monosomies than embryos derived from patient oocytes (41.2% vs. 25.4%, p < 0.05, respectively); however, only Trisomy 7 (0.4% vs. 2.3%, p < 0.05) and Trisomy in X (0.7% vs. 2.3%, p < 0.05) were significantly less present when compared to patient oocyte derived embryos. Interestingly, rates for embryo implantation (46.7% vs. 50.8%, p = 0.35), clinical pregnancy (38.5% vs. 43.1%, p = 0.30), and live birth (30.5% vs. 30.5%, p = 0.99) were similar for embryos derived from donor and patient oocytes. These results did not change when adjusted for the number of embryos implanted. CONCLUSION: Here, we show no significant differences in achieving pregnancy when using donor oocytes. Taking into consideration that aneuploidy rates are > 30% in embryos, independent of the oocyte origin, PGT should be recommended with donor oocytes as well.

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Classical 3ß-HSD deficiency due to mutations in the HSD3B2 gene is responsible for a rare form of congenital adrenal hyperplasia (CAH) and is identified by varying degrees of salt wasting. Preimplantation genetic diagnosis (PGD) was performed in a couple carrying mutation c.690 G>A in the HSD3B2 gene. Four polymorphic short tandem repeat markers closely linked to the HSD3B2 gene (D1S185, D1S453, D1S514, D1S540) for linkage analysis in conjunction with the direct mutation analysis were used in embryo genotyping. Two CODIS STRs (VWA and THO1) were also used to confirm embryo zygosity and rule out possible contaminations. Finally, SRY and AMYLOGENIN markers were used for embryo sex determination. PGD was performed by fluorescent multiplex seminested polymerase chain reaction and sequencing. Six embryos were tested and one male carrier embryo was transferred, resulting in the birth of a healthy boy.

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The development of new genomic technologies has strengthened the influence of genetics in all medical specialties; reproductive medicine is no exception. The introduction of new genetic tests to daily clinical practice, together with the complexity of genetic information and its potential psychological burden, make specialized genetic counseling essential. Preimplantation genetic testing for aneuploidies (PGT-A) has become an almost routine procedure in assisted reproduction treatments. Nevertheless, in Peru, patients usually receive none or inadequate corresponding genetic counseling, which hinders informed decision-making.

El desarrollo de las nuevas tecnologías genómicas ha potenciado la influencia de la genética en todos los campos de la medicina, en donde la medicina reproductiva no es la excepción. La frecuente introducción de nuevas pruebas genéticas en la práctica clínica diaria, junto con la complejidad de la información genética y su potencial carga psicológica, hacen indispensable el asesoramiento genético especializado. En este contexto, el diagnóstico genético preimplantacional para aneuploidías (PGT-A) se ha convertido en un procedimiento casi de rutina en los tratamientos de reproducción asistida. Sin embargo, en el Perú, en la gran mayoría de casos los pacientes no reciben el asesoramiento genético correspondiente o este no es el adecuado, que no permite una toma de decisiones informada.

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Objectives: To determine if the use of the KIDScore 5 algorithm (known implantation data) can help select between euploid embryos in order to improve pregnancy and implantation rates in patients undergoing assisted reproductive procedures. Methods: Retrospective cohort study in a fertility clinic, from October 2016 to December 2018, of 1 049 embryos from 328 patients. All the embryos were cultured in the Time-Lapse, Embryoscope® incubator (Vitrolife®, Canada) for 5-6 days. Of these, 896 embryos (85.4%) were biopsied and analyzed by NGS, and assessed with the predictive KIDScore 5 algorithm (Vitrolife®, Canada). The 153 remaining embryos (14.6%) were assessed with the predictive KIDScore 5 algorithm only. 256 single euploid embryos were transferred in couples undergoing IVF treatments at the Inmater clinics laboratory of assisted reproduction in Lima - Peru. Results: The implantation rate was significantly higher (p = 0.004) in euploid embryos transferred when selected by the KIDScore 5 algorithm (Group 2) versus those selected using only genetic study by NGS technology (Group 1) (71.2% vs. 48.8%). The rate of implantation of the euploid embryos transferred with KIDScore value = 6 versus those transferred with KIDScore = 1 was statistically different (73.5% vs. 50.8%; p = 0.030). When assessing the relationship between the rate of euploid embryos versus the result of the KIDScore 5 value, we found highly significant differences in the rates of euploid embryos with values 6 and 5 versus those with KIDScore 0 and 1 (60.5% vs. 45.7%; p = 0.0004). Conclusions: The embryo selection with the KIDScore 5 algorithm offers advantage on implantation and pregnancy rates only when euploid embryos are transferred. Its use as an additional criterion to embryo selection should be considered when accompanied by genetic study of the embryos to be transferred. Euploid embryos with a higher value in the KIDScore 5 algorithm scale have better rates of implantation and euploidy than embryos with the minimum value of this algorithm.

Objetivos. Evaluar si el uso del algoritmo KIDScore 5 (known implantation data) puede ayudar a seleccionar entre los embriones euploides, para mejorar las tasas de embarazo e implantación en pacientes sometidas a procedimientos de reproducción asistida. Métodos. Estudio de cohorte retrospectivo en una clínica de fertilidad, desde octubre 2016 a diciembre 2018. Se estudió 1 049 embriones provenientes de 328 pacientes. Todos los embriones fueron cultivados en la incubadora Time-Lapse, Embryoscope® (Vitrolife®, Canadá) durante 5 a 6 días. De estos, 896 embriones (85,4%) fueron biopsiados y analizados mediante NGS y recibieron una valoración otorgada por el algoritmo predictivo KIDScore 5 (Vitrolife®, Canadá). Los 153 embriones restantes (14,6%) únicamente recibieron la valoración mediante el algoritmo predictivo KIDScore 5. Se realizó 256 transferencias únicas de embriones euploides en parejas sometidas a tratamientos de FIV en el laboratorio de reproducción asistida de la Clínica Inmater, Lima - Perú. Resultados. La tasa de implantación de los embriones euploides transferidos con valores de KIDScore = 6 versus los transferidos con valores de KIDScore = 1 tuvo diferencia estadísticamente significativa (73,5% vs. 50,8%; p=0,030). Al evaluar la relación entre la tasa de euploidia embrionaria versus el resultado del valor de KIDScore 5, se obtuvo diferencias altamente significativas en las tasas de euploidia en los embriones con resultados de KIDScore 6 y 5 versus los de KIDScore 0 y 1 (60,5% vs. 45,7%; p=0,0004). Conclusiones. La selección embrionaria con ayuda del algoritmo KIDScore 5 ofrece ventaja en las tasas de implantación y embarazo únicamente cuando se transfieren embriones euploides. Su uso como criterio adicional a la selección embrionaria debiera ser considerado siempre que se acompañe estudio genético a los embriones a transferir. Los embriones euploides con valor más alto en la escala del algoritmo KIDScore 5, tienen mejores tasas de implantación y euploidía que los embriones con el valor mínimo de dicho algoritmo.

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Background: Hypohidrotic ectodermal dysplasia (HED) is a genetic skin condition presenting as hypohidrosis, hypodontia, and hypotrichosis, resulting in an important burden for affected families. The most common form of HED has an X-linked inheritance and female carriers have the option of prenatal or preimplantation genetic testing (PGT) to avoid transmission of the disease. A combined PGT for a mutation in EDA gene and aneuploidies in a Mexican carrier of X-linked HED is reported. Materials and Methods: Ovarian stimulation and assisted reproduction procedures were performed in a private academic medical center. PGT for a novel c.707-1G>A (rs886039466) mutation in EDA gene and chromosomal aneuploidies was performed by massive parallel and Sanger sequencing. Results: In the first PGT, the transfer of two blastocysts did not result in a pregnancy. An accumulative stimulation approach was decided to improve pregnancy chances for a second PGT procedure. Three ovarian stimulations were performed and 10 blastocysts coming from fresh and vitrified oocytes were genetically analyzed. A single embryo transfer produced a healthy non-carrier euploid girl. Discussion: PGT combining aneuploidy and mutation analyses is an alternative for female carriers of X-linked and other Mendelian disorders in Latin-American countries. In the era of genomic and personalized medicine, medically assisted reproduction techniques, such as PGT, are shifting from only infertility to preventive genetics.

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Abstract: 14. The purpose of preimplantation genetic diagnosis by embryonary biopsy is to identify genetic alterations prior to the implantation of embryos produced by in vitro fertilization. The most important aim is the selection of genetically healthy embryos due to their genetic indemnity, but it can also be used to select the sex or, eventually, other detectable traits accrding to the wishes of the parents. This procedure has been the subject of scientific debates, in relation to the harm that it can cause to healthy embryos that are going to be implanted, and in relation to the interpretation of the genetic tests made. Ethical debates have also focused on the production of and respect for the life and the integrity of developing human beings. In this work, it is argued that most of the uses of PGD are morally reprehensible, because they are done with disregard to the dignity that should be granted to embryos as human persons.

Resumen: 18. El diagnóstico genético preimplantacional (DGP) mediante biopsia embrionaria tiene como objeto la detección de alteraciones genéticas previamente a la implantación de embriones producidos por fertilización in vitro (FIV). Su finalidad más significativa es la selección de embriones por su indemnidad genética. También se puede emplear para seleccionar el sexo o eventualmente otras características detectadas según el deseo de los padres. Este procedimiento ha sido objeto de debates en el ámbito científico, por el eventual daño que puede ocasionar la técnica en embriones sanos que serán implantados y por las interpretaciones de los exámenes genéticos realizados. También ha sido objeto de debates en el ámbito ético-antropológico, en cuanto a la producción y al respeto a la vida e integridad de los seres humanos en desarrollo. En este trabajo se argumenta que los usos que se hacen del DGP son, en su gran mayoría, moralmente reprochables, por hacerse con desprecio de la dignidad que debe darse al embrión como persona humana.

Resumo: 22. O Diagnóstico genético pré-implantacional (PGD) por meio de biópsia embrionária visa a identificação de alterações genéticas prévias à implantação de embriões produzidos por fertilização in vitro (FIV). Seu propósito mais significativo é a seleção de embriões por sua característica genética. Ele também pode ser usado para selecionar o sexo ou, eventualmente, outras características identificadas de acordo com os desejos dos pais. Este procedimento tem sido tema de debate em âmbito científico, por eventual dano que pode ocaciosionar a técnica em embriões saudáveis que serão implantados e pela interpretações dos exames genéricos realizados. Ele também tem sido objeto de debate na área ético-antropológica, no que concerne a produção e o respeito à vida e integridade do ser humano em desenvolvimento. Este artigo argumenta que os usos que são feitos do PGD são, em sua grande maioria, moralmente condenáveis, por ser instrumentalizado com desrespeito pela dignidade que deve ser dada ao embrião como uma pessoa humana.

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Sickle cell anemia is an inherited systemic hemoglobinopathy that affects hemoglobin production in red blood cells, leading to early morbidity and mortality. It is caused by a homozygous nucleotide substitution (c.20A>T) in the ß-globin gene (HBB) that changes a glutamic acid to a valine in the protein. We present a case report of a fertile couple, both carriers of the sickle cell anemia mutation, with one affected daughter. Six cycles of assisted reproductive techniques were performed, resulting in 53 embryos in cleavage stage. Each embryo was biopsied and analyzed for pre-implantation genetic diagnosis (PGD) by fluorescent polymerase chain reaction, using polymorphic markers of the region of interest followed by capillary electrophoresis in an automated genetic analyzer. HLA Compatible and normal embryos for the mutation represented 3 (5.66%); while the carriers and compatible 6 (11.32%); therefore, embryos matching those of the affected daughter represented 9 (16.98%). A selected embryo in blastocyst stage was transferred, resulting in a healthy male newborn, who had the umbilical cord blood cells collected and stored. The affected daughter was immunosuppressed and received transplanted cells from the umbilical cord blood of her brother; the treatment was successful. Embryo selection using PGD technologies represent the most effective treatment plan for parents who want to have a healthy child, and it could cure another child already affected by inherited hemoglobinopathy.

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Preimplantation genetic diagnosis was carried out for embryonic analysis in a patient with multiple endocrine neoplasia type 1 (MEN1). This is a rare autosomal-dominant cancer syndrome and the patients with MEN1 are characterized by the occurrence of tumors in multiple endocrine tissues, associated with germline and somatic inactivating mutations in the MEN1 gene. This case report documents a successful preimplantation genetic diagnosis (PGD) involving a couple at-risk for MEN1 syndrome, with a birth of a healthy infant. The couple underwent a cycle of controlled ovarian stimulation and intracytoplasmic sperm injection (ICSI). Embryos were biopsied at the blastocyst stage and cryopreserved; we used PCR-based DNA analysis for PGD testing. Only one of the five embryos analyzed for MEN1 syndrome was unaffected. This embryo was thawed and transferred following endometrial preparation. After positive ßHCG test; clinical pregnancy was confirmed by ultrasound, and a healthy infant was born. PGD for single gene disorders has been an emerging therapeutic tool for couples who are at risk of passing a genetic disease on to their offspring.

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Cystic fibrosis is an autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator gene. This disorder produces a variable phenotype including lung disease, pancreatic insufficiency, and meconium ileus plus bilateral agenesis of the vas deferens causing obstructive azoospermia and male infertility. Preimplantation genetic diagnosis is an alternative that allows identification of embryos affected by this or other genetic diseases. We report a case of couple with cystic fibrosis; the woman had the I148 T mutation and the man had the Delta F508 gene mutation. The couple underwent in vitro fertilization, associated with preimplantation genetic diagnosis, and with subsequent selection of healthy embryos for uterine transfer. The result was an uneventful pregnancy and delivery of a healthy male baby.

A fibrose cística é uma doença autossômica recessiva causada por mutações no gene regulador de condutância transmembrana na fibrose cística. Produz fenótipo variável, incluindo doença pulmonar, insuficiência pancreática, íleo meconial, além de agenesia bilateral dos ductos deferentes, causando azoospermia obstrutiva e infertilidade masculina. O diagnóstico genético pré-implantacional é uma alternativa diagnóstica, que permite identificar embriões portadores de fibrose cística e outras doenças genéticas. Relatamos o caso de um casal portador de fibrose cística, sendo a mulher portadora da mutação I148 T e o homem da mutação gênica Delta F508. O casal foi submetido a técnicas de fertilização in vitro associadas ao diagnóstico genético pré-implantacional, com consequente seleção de embriões saudáveis, que foram transferidos para o útero, resultando em gravidez sem intercorrências e com feto saudável, do sexo masculino.

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INTRODUÇÃO: A infertilidade causada por fatores genéticos acomete um grande número de casais que buscam tratamento de reprodução humana assistida. O diagnóstico genético pré-implantacional (PGD) é uma técnica usada durante a reprodução humana assistida que investiga alterações cromossômicas e genéticas em embriões in vitro durante diferentes estágios de seu desenvolvimento e seleciona os embriões livres de alterações genéticas para implantação uterina. Três tipos de biópsia podem ser feitos no PGD: dos glóbulos polares, dos blastômeros e do blastocisto, em ordem cronológica de acordo com o desenvolvimento embrionário. OBJETIVO: Analisar a aplicabilidade e a relevância da técnica PGD na rotina laboratorial da reprodução humana assistida e revisar sua metodologia. MÉTODO: Revisão de literatura sobre a técnica e os questionamentos éticos envolvidos com o PGD. Resultados: Os dados existentes atualmente sugerem que não há efeitos detrimentais sobre os embriões que sofreram biópsia. No Brasil o PGD é visto como uma ferramenta no auxílio da reprodução humana assistida e apresenta questões éticas ainda em discussão. CONCLUSÕES: O PGD respeita a visão e os valores da sociedade que considera a saúde como um de seus maiores bens.

INTRODUCTION: Infertility caused by genetic factors affect a large number of couples seeking treatment assisted human reproduction. The preimplantation genetic diagnosis (PGD) is a technique used during assisted human reproduction that investigates chromosomal and genetic abnormalities in vitro embryos during different stages of development and select genetic healf embryos to the uterine implantation. Three types of biopsy may be performedin PGD: biopsy of polar cells, biopsy of blastomere and biopsy of the blastocyst in chronological order according to embryonic development. OBJECTIVE: to analyze the applicability and relevance ofthe PGD technique on human assisted reproduction laboratory routine and review its methodology. METHOD: This article provides an overview on the technical and ethical issues involved with PGD. RESULTS: Many studies suggest that there is currently no detrimental effects on embryos that underwent biopsy. PGD in Brazil is seen as a tool to aid in the assisted human reproduction and presents ethical issues still under discussion. CONCLUSIONS: The PGD respects the vision and values of the society that considers health asone of its greatest assets.

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Preimplantation genetic diagnosis (PGD) allows identifying genetic traits in early embryos. Because in some equine breeds, like Polo Argentino, females are preferred to males for competition, PGD can be used to determine the gender of the embryo before transfer and thus allow the production of only female pregnancies. This procedure could have a great impact on commercial embryo production programs. The present study was conducted to adapt gender selection by PGD to a large-scale equine embryo transfer program. To achieve this, we studied (i) the effect on pregnancy rates of holding biopsied embryos for 7 to 10 hours in holding medium at 32 °C before transfer, (ii) the effect on pregnancy rates of using embryos of different sizes for biopsy, and (iii) the efficiency of amplification by heating biopsies before polymerase chain reaction. Equine embryos were classified by size (≤300, 300-1000, and >1000 µm), biopsied, and transferred 1 to 2 or 7 to 10 hours after flushing. Some of the biopsy samples obtained were incubated for 10 minutes at 95 °C and the rest remained untreated. Pregnancy rates were recorded at 25 days of gestation; fetal gender was determined using ultrasonography and compared with PGD results. Holding biopsied embryos for 7 to 10 hours before transfer produced pregnancy rates similar to those for biopsied embryos transferred within 2 hours (63% and 57%, respectively). These results did not differ from pregnancy rates of nonbiopsied embryos undergoing the same holding times (50% for 7-10 hours and 63% for 1-2 hours). Pregnancy rates for biopsied and nonbiopsied embryos did not differ between size groups or between biopsied and nonbiopsied embryos within the same size group (P > 0.05). Incubating biopsy samples for 10 minutes at 95 °C before polymerase chain reaction significantly increased the diagnosis rate (78.5% vs. 45.5% for treated and nontreated biopsy samples respectively). Gender determination using incubated biopsy samples matched the results obtained using ultrasonography in all pregnancies assessed (11/11, 100%); untreated biopsy samples were correctly diagnosed in 36 of 41 assessed pregnancies (87.8%), although the difference between treated and untreated biopsy samples was not significant. Our results demonstrated that biopsied embryos can remain in holding medium before being transferred, until gender diagnosis by PGD is complete (7-10 hours), without affecting pregnancy rates. This simplifies the management of an embryo transfer program willing to incorporate PGD for gender selection, by transferring only embryos of the desired sex. Embryo biopsy can be performed in a clinical setting on embryos of different sizes, without affecting their viability. Additionally, we showed that pretreating biopsy samples with a short incubation at 95 °C improved the overall efficiency of embryo sex determination.

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Introducción: El diagnóstico genético preimplantacional (PGD) por medio de las técnicas de aCGH y polimorfismo de nucleótido único (SNPs - single nucleotide polymorphism) se ha convertido en una herramienta útil en los ciclos de reproducción asistida, superando al PGD por hibridación fluorescente in situ (FISH). Estas técnicas nos permiten conocer las aneuploidías en cada uno de los cromosomas. Además, la SNPs con Parental Support (Natera, Inc) posibilita conocer el origen de la aneuploidía en los blastocistos, si por el espermatozoide o por el ovo-cito. Objetivos: Determinar la tasa de aneuplodías únicas en embriones humanos obtenidos por reproducción asistida, utilizando la técnica de polimorfismo de nucleótido único. Diseño: Estudio retrospectivo. Institución: Grupo PRANOR, Sede Monterrico, y Genomics Perú, Lima, Perú. Material biológico: Embriones humanos. Intervenciones: Análisis de los registros de 429 embriones estudiados con PGD por SNPs, embriones obtenidos de 105 ciclos de reproducción asistida, entre 2011 y 2013. Principales medidas de resultados: Aneuploidía de embriones, relación con edad materna y origen paterno o materno. Resultados: El 48,8% de embriones resultó normal, con tasa de aneuploidía de 51,2%. La proporción de embriones sanos varió de acuerdo a la edad de la madre, disminuyendo cuando la edad aumentaba. En todos los grupos etarios estudiados más de 66% de las aneuploidías fue de origen materno, incluyendo el grupo de ovodonación (OD). Conclusiones: El diagnóstico preimplantacional mediante SNPs tendría gran valor pronóstico y sería una herramienta útil para conocer el origen de las aneuploidías en los embriones de las pacientes que se someten a procedimientos de reproducción asistida.

Background: Preimplantation genetic screening (PGS) using comparative genomics hybridization (aCGH) and single nucleotide polymorphism (SNP) technology has become a useful tool in assisted reproduction by improving clinical outcomes. Both techniques identify aneuploidies and chromosomal rearrangement. However, SNPs with Parental Support (Natera Inc.) give extra information of the aneuploidy origin either from the sperm or the oocyte. Objectives: To determine single aneuplodies rate in human embryos obtained by assisted reproduction using single nucleotide polymorphism microarray. Design: Retrospective study. Setting: Grupo PRANOR, Sede Monterrico, and Genomics Peru, Lima, Peru. Biologic material: Human embryos. Interventions: From 2011 to 2013, 105 patients underwent IVF/ ICSI with SNPs and Parental Support. In total, 429 embryos were analyzed and records were reviewed. Main outcome measures: Embryos aneuploidy, relation with maternal age and paternal or maternal origin. Results: From the 429 embryos 208 (48.8%) were chromosomally normal. The proportion of normal embryos decreased with increasing maternal age. In all age groups more than 66% of aneuploidies had maternal origin, including the ovodonation group (OD). Conclusions: PGS by SNPs with Parental Support resulted in good prognostic value and would be useful in determining the origin of aneuploidy in embryos of patients who underwent assisted reproduction technology.

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Introducción: De las causas más conocidas en cuanto a la falta del éxito en el embarazo con tratamientos de reproducción asistida son aquellas relacionadas a las aneuploidías cromosómicas presentes en los embriones. El diagnóstico genético preimplantacional (PGD) es una técnica empleada en reproducción asistida para detectar estas anomalías, seleccionando aquellos que sean cromosómicamente normales, para luego transferirlos al útero de la paciente. Los embriones con aneuploidías únicas podrían tener la capacidad de sobrevivir y lograr la implantación, y por lo tanto, sin diagnóstico previo, estas podrían pasar desapercibidas. Objetivos: Determinar la incidencia de aneuploidías únicas en embriones de buena calidad embrionaria en el día 3 de desarrollo hasta blastocisto. Diseño: Estadístico y experimental. Instituciones: Reprogenetics Latinoamérica y Centro de Reproducción asistida, de la Clínica Concebir. Material Biológico: Muestras de biopsia embrionaria. Metodología: Análisis comparativo de resultados a partir de la evaluación de cada muestra obtenida por biopsia en el día tercero y día quinto de desarrollo embrionario, realizando el PGD por hibridación in situ (FISH) y genómica comparada (aCGH), respectivamente. Resultados: El 62,9% de embriones que presentaron monosomías únicas al tercer día de desarrollo embrionario resultaron ser de 8 células. Pero cuando se evaluó por aCGH en día cinco, 42,3% resultó anormal, y de estos 37,5% perteneció al estadio de 8 células. El índice de monosomías únicas en blastocisto resultó ser 57,9% de un total de 84,2% de aneuploidías únicas. Conclusiones: Los embriones de 8 células en el tercer día de desarrollo embrionario son los más probables de llegar al estadio de blastocisto, así como presentar aneuploidías únicas.

Background: Known causes of unsuccessful pregnancy in couples undergoing assisted reproduction treatment include embryo aneuploidies. Preimplantation genetic diagnosis (PGD) is a technique used in assisted reproduction in order to detect these abnormalities, select embryos chromosomally normal and subsequently transfer to the patients’ uterus. Embryos with single aneuploidies may have the ability to survive and achieve unnoticed implantation. Objectives: To determine incidence of single aneuploidies in good quality embryos in third day of development to blastocyst. Design: Statistical and experimental study. Setting: Reprogenetics Latin-America and Assisted Reproduction Center - Concebir. Biologic material: Samples of embryo biopsies. Methods: Comparative analysis of results from evaluation of each sample obtained by embryo biopsy on the third and fifth days of embryonic development, performing PGD by respectively in situ hybridization (FISH) and comparative genomics (aCGH). Results: On third day of embryonic development 62.9% of embryos with single monosomy had 8-cell morphology. Though when evaluated by aCGH in the blastocyst stage 42.3% were abnormal and 37.5% of these belonged to the 8-cell stage. Single monosomies index in the blastocyst stage was 57.9% in 84.2% of single aneuploidies. Conclusions: Eight-cell embryos on the third day of embryonic development are most likely to reach blastocyst stage and have single aneuploidies.

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A fibrose cística (FC) é a doença autossômica recessiva mais comum em euro-descendentes, com uma incidência estimada de 1 caso a cada 2.500 nascimentos. A FC é uma doença multissistêmica, caracterizada principalmente por doença pulmonar progressiva, disfunção pancreática exócrina e concentração elevada de eletrólitos no suor. O gene associado a essa doença é denominado CFTR e se localiza no cromossomo 7, sendo dividido em 27 éxons. Até o momento, mais de 1.800 variações de sequência foram identificadas no gene CFTR, sendo que a mutação p.Phe508del é a mais frequente entre os pacientes de FC. No Brasil, a frequência dessa mutação não é tão elevada, devido provavelmente à miscigenação e, consequentemente, o locus CFTR apresenta maior heterogeneidade alélica. A probabilidade de um filho afetado com FC é de 1 em 4, ou 25%, para filhos de um casal em que ambos são portadores de uma mutação. O risco de um indivíduo com FC ter filhos afetados depende de seu parceiro – se o parceiro for portador da doença o risco será de 50%. Para casais em risco de terem filhos com FC e com mutação ou mutações identificadas, é possível oferecer diagnóstico pré-natal (DPN) e diagnóstico genético pré-implantacional (DPI). Considerando a complexidade da informação genética relacionada à FC e das alternativas reprodutivas que estão surgindo, é muito importante a disponibilização do aconselhamento genético para o paciente e sua família.

Cystic fibrosis (CF) is the most common autosomal recessive disease in European-derived populations, with an estimated incidence of 1/2,500 live births. CF is a multisystem disease, mainly characterized by progressive obstructive pulmonary disease, pancreatic insufficiency, and high electrolyte levels in sweat. The gene responsible for CF (CFTR) is located on chromosome 7, which comprises 27 exons. More than 1,800 sequence variations have been reported in the CFTR gene so far, and the p.Phe508del mutation is the most frequent among patients with CF. In Brazil, the frequency of p.Phe508del is lower than in other countries probably because of population admixture. This indicates that the CFTR locus may be more heterogeneous. For a couple with both parents carrying CF mutations, the probability of having a child with CF is 1 in 4, or 25%. The risk of having a child with CF for a CF patient depends on his/her partner – if the partner is a carrier of a CF mutation, the risk is 50%. For couples at risk of having a child with CF and with known CF mutations, it is possible to offer prenatal diagnosis (PND) and preimplantation genetic diagnosis (PGD). Considering the complexity of the genetic information related to CF and the reproductive alternatives that are emerging, it is very important to offer genetic counseling for patients and their families.

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Background: Infertility is a disease observed in approximately 10% of the reproductive age population (20-44 years old), and is defined as the failure to conceive after twelve months of regular sexual intercourse, without contraception; in women older than 35 years old, this period is reduced to 6 months. The main causes of infertility are tubal, ovarian and uterine and sperm abnormalities, endometriosis, and those with undetermined causes. Over the past 30 years, several techniques were developed to overcome these factors including gamete cryopreservation, controlled ovarian stimulation, intra-uterine insemination, in vitro fertilization, intracytoplasmatic sperm injection). Review: Despite advances in assisted reproductive technologies (ART), treatment success is still strongly dependent on oocyte and sperm quality, and resulting embryo viability. The most promising advance on oocyte quality assessment is the evaluation of the ovarian reserve by the quantification of the anti-müllerian hormone (AMH). Since ovarian reserve is closely related to oocyte quality, AMH levels could be an indicator of both oocyte production capacity and the potential of these oocytes to generate a viable embryo. On the other hand, despite the development of techniques to overcome male factor infertility, attention has been paid on the semen evaluation, since routine sperm evaluation techniques are known to be ineffective, especially in those cases of unexplained infertility. Therefore, techniques were developed to assess acrosome and membrane integrity, mitochondrial potential, DNA integrity, and fertilizing capacity of sperm. However, further studies are necessary to evaluate sperm DNA integrity without damaging the cell, allowing the injection of a spermatozoon with an intact DNA when using ICSI. Regarding embryo quality, even with a good quality oocyte (as assessed by the current techniques) and an apparently normal sperm, there are still chances of generating an embryo with genetic abnormalities. In such cases, and in cases of recurrent failures, women over 35 years of age, and couples with a pre-existing genetic risk, the preimplantation genetic diagnosis (PGD) appears to be an important tool to improve the odds of pregnancy and avoid abortions or the conception of fetuses with genetic abnormalities. The technique of PGD, usually performed with PCR or FISH, has gained a powerful tool with the development of the Comparative Genomic Hybridization (CGH). However, recent studies aiming to identify markers of oocyte and sperm quality and embryo viability are in course using mass spectroscopy. With this sensitive technique applied to body fluids (i.e., blood, follicular fluid, seminal plasma), granulosa cells, sperm, and culture media, researches are being conducted to non-invasively identify biomarkers that will help understand reproductive mechanisms and to efficiently predict the outcome of ARTs. Conclusion: Significant advances in ART have been observed in the last few years, yet, failures still occur with high frequency. This review will focus on techniques to assess oocyte quality, sperm function and embryo viability, aiming to provide tools for a precise prognosis when treating infertile couples.

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Se describen los inicios de las técnicas de fertilización in vitro en el mundo y Bolivia y los aspectos más influyentes para el éxito de las mismas, las tasas y los beneficios a corto plazo, riesgos materno fetales y embrionarios y los últimos avances para mejorar los resultados; basados en la evidencia actual. Previo análisis de la pareja que consulta por infertilidad.

We describe the early days ofin vitro fertilization techniques in the world and in Bolivia and the most influential aspects for their success rates ande benefits in short term, maternal, fetal and embryonic risks and the latest advances to improve assisted reproduction results, based on current evidence. Previous analysis ofcouples Consulting for infertility.

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Identificar um embrião com alto potencial de implantação é um dos maiores desafios da medicina reprodutiva e um passo fundamental em direção à transferência de um único embrião. O diagnóstico genético pré-implantacional permite identificar alterações genéticas ou cromossômicas nos embriões em divisão antes de serem transferidos, enquanto o rastreamento genético pré-implantacional realiza a triagem em embriões quanto às anomalias cromossômicas frequentes. Dentre as limitações encontradas, o mosaicismo é responsável por grande parcela de erros de diagnóstico, e os altos custos das técnicas de hibridização in situ por fluorescência e reação em cadeia da polimerase ainda dificultam a implantação do diagnóstico genético pré-implantacional e do rastreamento genético pré-implantacional de forma rotineira. Este artigo pretende apresentar uma visão geral acerca das modalidades de avaliação genética préimplantacional disponíveis e seus resultados e avaliar criticamente a inserção dessas tecnologias entre os recursospropedêuticos para assistência reprodutiva.

The identification of an embryo with high implantation potential is one of the greatest challenges in reproductive medicine and a vital step towards transferring a single pre-embryo. Preimplantation genetic diagnosis allows the identification of genetic or chromosomal alterations in pre-embryos before they are transferred to the uterus, while preimplantation geneticscreening determines alleatory frequent chromosomal abnormalities. Among limitations, mosaicism is responsible for a large proportion of misdiagnosis, and the high costs of fluorescent in situ hybridization and polymerase chain reaction still hinder the implementation of preimplantation genetic diagnosis and preimplantation genetic screening as a routine. Thisarticle aims to present an overview of possible modalities of preimplantation genetic evaluation and their results and to criticallyevaluate the insertion of those technologies in the propaedeutical tools in reproductive assistance.