Adverse effects of therapeutic phlebotomies: Prospective study of 587 procedures.

BACKGROUND: Therapeutic phlebotomy (TP), a widely used medical procedure, can be performed on diverse patients with iron overload or polyglobulia. However, its adverse events are not well known as most of the information on phlebotomy is derived from healthy blood donors (0.1%-5.3%). In contrast, TP is applicable to a broader, more complex population with comorbidities and old age. To ascertain the incidence of adverse events in phlebotomies, we conducted a prospective study on patients who attended our Unit. STUDY DESIGN AND METHODS: We prospectively gathered data from patients referred to our Unit for TP. Data regarding demographics, health status, and adverse events within at least 24 h of phlebotomy were gathered via a structured questionnaire during each visit. RESULTS: Between August 2021 and September 2022, 189 patients underwent 587 procedures. Most patients were men, over 60 (57.3%) had comorbidities, and 93% underwent at least two procedures during the study period. Twenty patients (10.8%) presented 25 adverse events (4.3% of phlebotomies), usually vasovagal reactions, none of which were clinically relevant, and all were managed by nursing staff on site, with full patient recovery. DISCUSSION: The rate of adverse events (<5%) in patients undergoing TP was low and comparable to that seen in healthy blood donors. Consequently, even old patients and those with some comorbidities can safely undergo TP when the process is carefully managed.

[What issues, changes and adaptations for French ART centers in the context of the new bioethics law?] / Quels enjeux et adaptations pour les centres d'AMP dans le cadre de la mise en place de la nouvelle loi de bioéthique ?

OBJECTIVE: This review intends to introduce the changes of the new Bioethics law in the reproductive field and its application in French ART centers. MATERIAL AND METHODS: The review details the main provisions of the Bioethics Law of August 2nd 2021 as well as the three decrees published since: the first one on September 29th 2021, which specifies in particular the age conditions to benefit from ART and self-preservation of one's gametes; another decree on December 31st, 2021, to set the terms and conditions for gamete self-preservation activities for non-medical reasons and the last decree on April 14th 2022, relating to the allocation of donated gametes and embryo donation. RESULTS: Since the law of August 2nd, 2021, access conditions to assisted reproductive technology (ART) have evolved in France. Previously based on pathological infertility or the risk of transmission of a serious disease, ART is now intended to respond to the parental project of a couple formed by a man and a woman, two women or an unmarried woman. With the widening of access conditions, the use of gamete donation will likely increase. The upcoming raise of children born from gamete donation has led the legislator to question their right to access their origin. From September 1st 2022, adults born from gamete donation will be able to request a special administrative authority in order to access the donor's non identifying data (age, physical characteristics, family and professional situation, motivation for the donation…) and/or the donor's identity. Moreover, the new bioethics law opens up the possibility of autologous gamete cryopreservation without medical reasons, under specific age conditions, in order to carry out an assisted reproduction technique later. If gametes are not used, autologous gamete preservation could also allow an increase in gamete donation. However, the modification of gamete donation conditions could suggest a short term decrease in donors' number. Finally, the new bioethics law further opens up research on human embryos and embryonic stem cells. CONCLUSION: The arrangements introduced by the Bioethics Law promulgated on August 2nd, 2021 represent a major revolution in the field of Reproductive Medicine and are expected to transform the practices of reproductive biology centers and CECOS in France.

Activated prothrombin complex concentrate to treat bleeding events in acquired hemophilia A: BAHAS study.

OBJECTIVE: Activated prothrombin complex concentrate (aPCC) is a bypassing agent indicated to treat bleeds in patients with acquired hemophilia A (AHA). Nevertheless, its efficacy and safety in the real-world setting have not often been addressed. METHODS: We report the experience of Spanish reference centers for coagulation disorders and from acquired hemophilia Spanish Registry (AHASR) from August 2012 to February 2021. Follow-up period of 30 days after aPCC withdrawal. RESULTS: Thirty patients with a median age of 70 years old, suffering from 51 bleeds treated with aPCC were finally evaluated. As first-line treatment, aPCC stopped bleeding in 13 of 14 (92.9%) cases. aPCC as the second line after recombinant factor VIIa failure, stopped bleeding in all cases. In 17 patients, aPCC was used far from initial bleed control as prophylaxis of rebleeding with 94% effectiveness. No thromboembolic episodes were communicated. One patient developed hypofibrinogenemia, which did not prevent aPCC from halting bleeding. No other serious adverse events possibly or probably associated with aPCC were reported. CONCLUSIONS: This data support aPCC as hemostatic treatment in AHA with high effectiveness and excellent safety profile in acute bleeds and as extended use to prevent rebleedings, even in aging people with high cardiovascular risk.

[HLA-C KIR interactions and placental defects: Implications in ART pregnancy issues]. / Interactions HLA-C KIR et anomalies de la placentation : implications dans les issues de grossesses obtenues en AMP.

OBJECTIVE: The aim of this review is to update data concerning the impact of HLA-C KIR system on placental disorders and assess the involvement on ART clinical outcomes. METHOD: Ensuring the maintenance of human pregnancy requires the set up of immunological tolerance to prevent foetus rejection. This phenomenon involves different actors of the immune system: among them, uterine NK cells (uNK) hold specific KIR (killer-cell immunoglobulin-like) receptors linking to HLA molecules on the surface of trophoblastic cells at implantation. Many studies provided evidence that the specific interaction between maternal KIR and foetal HLA-C could influence the process of placentation; according to the KIR haplotype and the type of HLA-C, the interaction could be detrimental for placental function. We reviewed the latest data available regarding HLA-C KIR interactions and ART outcomes. RESULTS: The available results highlight a significant increase of preeclampsia risk and recurrent miscarriages when the maternal inhibitory haplotype KIR AA is present, this risk is all the more enhanced when the interaction occurs with foetal HLA-C2. Recent data suggest the consequences of this detrimental interaction in case of DET (double embryo transfer) or use of donor's oocytes in ART practice. On the other hand, maternal KIR AB or BB haplotypes haven't been related to an additional obstetrical risk, as well as the foetal HLA-C1 homozygous allotype. CONCLUSION: Despite the existence of many confoundings in current literature on the subject, interaction between maternal KIR and foetal HLA-C represent a promising target lead to broaden the spectrum of placental defects etiologies, especially in the reproductive health area.

Knowledge of Epilepsy and seizure first aid among teachers in Jeddah, Saudi Arabia.

PURPOSE: Epilepsy is one of the most common neurological disorders, with a national prevalence of 6.54/1000. The majority of the patients are adolescents and at risk of experiencing a seizure in school. Consequently, schoolteachers would be among the first health care providers. Thus, teachers' knowledge and practice are imperative for the students' safety and development. We aimed to assess the knowledge of epilepsy and seizure first aid among teachers at all educational levels in Jeddah, Saudi Arabia. METHOD: A cross-sectional study using a self-administered validated questionnaire was distributed to teachers to assess their necessary demographic data and their knowledge about epilepsy and seizure first aid by using Chi-square test to find significant associations. RESULTS: Our sample included 822 teachers, 54.1% of the respondents were male, and 45.7% female. The majority of participants had moderate knowledge of epilepsy and lacked first aid training. Most participants recognized epilepsy as a neurological disorder, and 42.2% have witnessed a seizure in school. Our study showed a significant relationship between knowledge score and qualification (P-value = 0.037) as well as knowledge score and witnessing a seizure (P-value = 0.046). CONCLUSION: The knowledge score shows that teachers in Jeddah have moderate knowledge of epilepsy, and approximately one-tenth have taken first aid training. We recommend educational campaigns on epilepsy and first aid courses targeting students and teachers in schools.

[Assessment of genital microbiota: An emerging approach in assisted reproductive techniques]. / Évaluation du microbiote génital : une approche émergente en assistance médicale à la procréation.

The genital microbiota actively participates in women's reproductive health. Indeed, a genital dysbiosis (microbial imbalance associated with adverse effects on host health) can lead to vaginal infections (such as mycoses or bacterial vaginosis). Recent data reported that genital dysbiosis (e.g. vaginal or endometrial) was associated with fewer chances of live births in assisted reproductive technologies (ART), via decreased pregnancy rates and an increased risk of miscarriages. The presence or diversity of certain bacterial strains (in particular Gardenellavaginalis, Proteobacteria, Lactobacillusjensenii, Lactobacilluscrispatus or Atopobiumvaginae) within the genital microbiota seem to be associated with the outcomes of ART cycles, suggesting new approaches to improve ART results. In this review, we aim at presenting the state of art on the association between the female genital microbiota and ART success. The diagnostic and therapeutic approaches (i.e. probiotics, antibiotic therapy and transplantation of vaginal microbiota) in the management of patients with altered microbiota will also be discussed. The confirmation of these data in the coming years could significantly improve the management of infertile patients in ART with a more personalized approach partially based on the female genital microbiotic profile.

[Endometrial receptivity in assisted reproductive techniques: An aspect to investigate in embryo implantation failure]. / La réceptivité endométriale en aide médicale à la procréation : Une piste à ne pas oublier devant un échec d'implantation.

Infertility affects between 8 and 12% of reproductive-age couples worldwide. Despite improvements in assisted reproductive techniques (ART), live birth rates are still limited. In clinical practice, imaging and microscopy are currently widely used, but their diagnostic effectiveness remains limited. In research, the emergence of innovative techniques named OMICS would improve the identification of the implantation window, while progressing in the understanding of the pathophysiological mechanisms involved in embryo implantation failures. To date, transcriptomic analysis seems to be the most promising approach in clinical research. The objective of this review is to present the results obtained with the different approaches available in clinical practice and in research to assess endometrial receptivity in patients undergoing ART.

The Application of Radiofrequency Waves in Supportive Treatment of Temporomandibular Disorders.

In recent years, the number of patients applying for prosthetic treatment due to temporomandibular joint disorders (TMD) has been increasing. The main methods for treating disorders are the use of occlusal splints and physiotherapeutic rehabilitation as supportive treatment. Radio waves are electromagnetic waves with radiation frequency between 3 Hz and 3 THz, used for physiotherapeutic treatment of skeletal muscle relaxation in the range of 3 to 6 MHz. The rehabilitation effect of these waves is based on diathermy by means of high-voltage quick alternating current. Aim. The aim of the study was to evaluate the influence of radiofrequency waves on the pain of the masticatory muscles in the course of TMD and the usefulness of these procedures in the supporting treatment of these disorders. Materials and Methods. Patients aged 19 to 45 years, of both sexes, reported to the Consulting Room of TMD at the Institute of Dentistry in Krakow to undertake prosthetic treatment of TMD (I a-according to RDC/TMD). Study group (SG) consists of 20 patients who had 10 supportive treatments with radiofrequency currents. In the case of application of radiation to the muscle area, the energy was 20 J to the area of the masticatory muscles, the frequency was 3 MHz, bipolar technique, the duration of the procedure was 10 minutes, and the coupling substance was a gel for ultrasound examinations. The control group (CG) consisted of 20 patients who had 10 supportive treatments with sonophoresis procedures. For the area of masticatory muscles, 0.9 W/cm2 treatments were applied, the duty factor was 80%, the treatment time was 10 minutes, and the medical substance was 25% Voltaren gel. Results. Analysis of the results of the first clinical examinations (axis I) conducted in both groups shows a homogeneous clinical material and similar results. The second clinical examination revealed improved clinical parameters, but it showed a greater improvement in the SG. In the SG, the mean level of VAS was 6.25, and the extreme values were 5.9-0.14, the median was 2.15, and the standard deviation was 1.54. In the CG, the average value of VAS was 6.20 (peak of 5.2-0.7), the median was 2.4, and the standard deviation was 1.87. Summary. The search for new methods of supportive treatment of TMD is an important research direction due to the complex etiology of this disease and the lack of an explicit treatment algorithm. Conclusion. The results of our own research clearly indicate that the use of the radiofrequency waves brings pain relief and improvement of clinical parameters to a greater extent than in sonophoresis. It can be a very important new method in supportive treatment of TMD. Research needs to be continued.

[Comparison of birth weights of children born after slow frozen embryo replacement versus fresh embryo transfer]. / Embryons vitrifiés, embryons frais : comparaison des poids de naissance.

OBJECTIVE: It is already known that children born after slow frozen embryo replacement have a significantly higher birth weight compared to children born after fresh embryo transfer. Similar data have been reported related to frozen embryo transfer using an open vitrification system. However, few data relative to birth weight using a complete embryo closed vitrification system has been reported. The purpose of this study was to know if frozen embryo in closed vitrification system is associated with a higher birth weight compared to fresh embryo replacement. DESIGN: This was a monocentric retrospective cohort study, 371 children were issued from fresh embryo replacement and 127 from vitrified embryo transfer. MATERIALS AND METHODS: All singletons born after fresh or vitrified embryo transfer between January 2011 and April 2015 were included. Births from the vitrified or fresh transfers of egg or sperm donation, and preimplantation genetic diagnosis were excluded. In addition, pregnancies with more than one gestational sac at the first ultrasound were excluded. An analysis of covariance (ANCOVA) was used for multivariate analysis. RESULTS: Mean birth weight was 205g higher in the frozen embryo compared with fresh embryos transfer groups (3368g vs. 3163g respectively, P<0.001). This difference remained after multivariate analysis adjusted on confounding factors such as gestational age, maternal age, maternal body mass index (BMI), tobacco exposure, number of embryo transferred and birth order (P<0.001).. CONCLUSIONS: Embryo frozen in closed vitrification system is associated with a higher birth weight compared to fresh embryo replacement. Our findings are consistent with the previous studies related to slow freezing and open vitrification systems data. The effects of controlled ovarian stimulation (COS), ex vivo culture conditions and cryopreservation systems on birth weight of children born should be further explored.

Magnitud y características de la intoxicación por alcohol metílico. Hospital Nacional Dos de Mayo / Magnitude and features of methanol poisoning. Hospital Nacional Dos de Mayo

Objetivo: Determinar la magnitud, características clínicas y bioquímicas de la intoxicación por alcohol metílico en pacientes admitidos al Servicio de Emergencia del Hospital Nacional Dos de Mayo. Materiales y métodos: Estudio analítico. La población fueron los pacientes que ingresaron a Emergencia del Hospital Nacional Dos de Mayo con diagnóstico de intoxicación por metanol (CIE 10: T51.1). Las variables fueron epidemiológicas (edad, sexo, ocupación, uso de narcóticos, cocaína, alcoholismo crónico e infección por HIV), clínicas (intoxicación por metanol) y bioquímicas (glicemia, urea, creatinina, electrolitos séricos y, especialmente, metanolemia). Se empleó el software SPSS, versión 23.00. Se determinaron medidas de tendencia central y de dispersión, y también Odds Ratio con sus respectivos intervalos de confianza al 95 %, se consideró estadísticamente significativo el valor de p< de 0,05. Resultados: El 90 % de casos fue ocasionado por ingesta accidental de bebida adulterada. El 87,5 % de los pacientes eran de nivel socioeconómico bajo. La metanolemia promedio fue de 72,04 mg/L (DE+39,70) y la mortalidad global fue de 12,5 %. El perfil bioquímico predominante fue acidosis metabólica severa con anión gap elevado. Conclusiones: La intoxicación por metanol representa el 0,15 % del total de consultas de emergencia; el perfil clínico se caracteriza por hipotensión, taquicardia, taquipnea, asociado a trastorno del sensorio, vómitos, midriasis y nistagmo, respectivamente. La acidosis metabólica severa se relacionó con incremento de morbimortalidad

Objective: To determine the magnitude, and clinical and biochemical features of methanol poisoning in patients admitted to the emergency room of the Hospital Nacional Dos de Mayo. Materials and methods: An analytical study was performed with data from patients diagnosed with methanol poisoning who were admitted to the emergency room of the Hospital Nacional Dos de Mayo, Lima, Peru. Collected data included age, gender, occupation, place of origin, cocaine use, chronic alcoholism, HIV infection, and clinical data associated with methanol poisoning. For the analysis, statistical measures of central tendency and dispersion were used, and 2x2 contingency tables were developed in the bivariate analysis. For the evaluation of the likelihood ratio, confidence intervals were established at 95 %, and a p-value < 0.05 was considered significant. Results: Ninety percent (90%) of the cases occurred due to the accidental ingestion of an adulterated drink. Eighty- seven point five percent (87.5 %) of the patients had low socioeconomic status. Average blood methanol level was 72.04 mg/L (SD ± 39.70) and overall mortality was 12.5 %. The predominant biochemical profile was severe high-anion gap metabolic acidosis. Conclusions: Methanol poisoning accounts for 0.15 % of total emergency room consultations. Its clinical profile is characterized by hypotension, tachycardia, tachypnea, sensory disorders, vomiting, mydriasis and nystagmus. Severe metabolic acidosis was associated with increased morbidity and mortality

[Birth weight and frozen embryo transfer: State of the art]. / Poids de naissance et transfert d'embryon congelé : état de l'art.

The aim of this study was to update our acknowledgment if there is a link between assisted embryo cryopreservation and epigenetics in human? Animal studies have demonstrated epigenetics consequence and especially imprinting disorders due to in vitro culture. In human, it is important to note that after frozen embryo transfer birth weight is significantly increased by 81 to 250g. But these studies cannot identify the reasons of such difference. This review strongly suggests that embryo cryopreservation is responsible for birth weight variations but mechanisms not yet elucidated. Epigenetics is probably one of these but to date, none study is able to prove it. We have to be attentive on a possible link between assisted reproductive technology (ART) and epigenetics reprogrammation.

[Quality of oocytes and embryos from women with polycystic ovaries syndrome: State of the art]. / Qualité ovocytaire et embryonnaire chez les femmes avec syndrome des ovaires polykystiques : état de l'art.

The frequency of polycystic ovary syndrome (PCOS) and the consequent fertility disorders cause many difficulties in the management of the assisted reproductive technics. Some studies are focused on different additional treatments, stimulation protocols or techniques that could optimize the in vitro fertilization cycles. The quality of the oocytes and embryos of these patients is also an outstanding issue. They remain difficult to actually evaluate during management, and none of the few published studies on this subject demonstrated any inferiority, compared to control patients. However, many differences have been highlighted, studying intra- and extra-ovarian factors. The advent of new genetic techniques could allow a better understanding of the pathophysiological mechanisms of the syndrome, as well as refining the evaluation of oocytes and embryos, in order to better predict the results of in vitro fertilization attempts. Pregnancy and birth rates, however, appear to be comparable to those of the general population.

Retrograde transport of TrkB-containing autophagosomes via the adaptor AP-2 mediates neuronal complexity and prevents neurodegeneration.

Autophagosomes primarily mediate turnover of cytoplasmic proteins or organelles to provide nutrients and eliminate damaged proteins. In neurons, autophagosomes form in distal axons and are trafficked retrogradely to fuse with lysosomes in the soma. Although defective neuronal autophagy is associated with neurodegeneration, the function of neuronal autophagosomes remains incompletely understood. We show that in neurons, autophagosomes promote neuronal complexity and prevent neurodegeneration in vivo via retrograde transport of brain-derived neurotrophic factor (BDNF)-activated TrkB receptors. p150Glued/dynactin-dependent transport of TrkB-containing autophagosomes requires their association with the endocytic adaptor AP-2, an essential protein complex previously thought to function exclusively in clathrin-mediated endocytosis. These data highlight a novel non-canonical function of AP-2 in retrograde transport of BDNF/TrkB-containing autophagosomes in neurons and reveal a causative link between autophagy and BDNF/TrkB signalling.

Eslicarbazepine acetate as adjunctive therapy in clinical practice: ESLADOBA study.

OBJECTIVE: To assess seizure control and tolerability of eslicarbazepine acetate (ESL) as adjunctive therapy to one baseline antiepileptic drug (AED), in adults with partial-onset seizures (POS) with or without secondary generalization. METHODS: Multicenter, non-interventional, prospective cohort study conducted between March 2012 and September 2014 at 12 neurology departments in Portugal. Adults with POS not controlled with one AED who had initiated ESL as adjunctive treatment were enrolled. Retention rate was defined at the final visit (Vfinal) 6-9 months of follow-up. Proportion of responders, seizure-free, changes in seizure frequency were evaluated using patients' diaries. Clinical Global Impression of Change (CGI-C) and Clinical Global Impression of Severity (CGI-S) were assessed by the neurologist. RESULTS: Fifty-two patients (48.1% male) were included with mean age 41.5±13.3 years. Mean epilepsy duration was 18.5±14.8 years; mean seizure frequency in the four previous weeks to baseline was 7.5±12.7. At Vfinal, retention rate was 73.0%; responder rate and seizure-free rates were 71.1% and 39.5%, respectively. The median relative reduction in seizure frequency between baseline and Vfinal was 82.2%. A reduction in epilepsy severity (CGI-S) was observed in 42.1%. According to CGI-C, 73.6% patients had their epilepsy "much improved" or "very much improved". Twelve patients (23.1%) had at least one adverse event (AE), two (3.9%) had one serious AE, and five (9.6%) discontinued due to AE. CONCLUSIONS: Eslicarbazepine acetate showed good retention rates, elicited a significant reduction in seizure frequency, and was well tolerated when used in the clinical practice.

Young, active and well-connected: adult-born neurons in the zebra finch are activated during singing.

Neuronal replacement in the pallial song control nucleus HVC of adult zebra finches constitutes an interesting case of homeostatic plasticity; in spite of continuous addition and attrition of neurons in ensembles that code song elements, adult song remains remarkably invariant. New neurons migrate into HVC and later synapse with their target, arcopallial song nucleus RA (HVCRA). New HVCRA neurons respond to auditory stimuli (in anaesthetised animals), but whether and when they become functionally active during singing is unknown. We studied this, using 5-bromo-2'-deoxyuridine to birth-date neurons, combined with immunohistochemical detection of immediate-early gene (IEG) expression and retrograde tracer injections into RA to track connectivity. Interestingly, singing was followed by IEG expression in a substantial fraction of new neurons that were not retrogradely labelled from RA, suggesting a possible role in HVC-intrinsic network function. As new HVC neurons matured, the proportion of HVCRA neurons that expressed IEGs after singing increased significantly. Since it was previously shown that singing induces IEG expression in HVC also in deaf birds and that hearing song does not induce IEG expression in HVC, our data provide the first direct evidence that new HVC neurons are engaged in song motor behaviour.

[Circulating nucleic acids and infertility]. / Les acides nucléiques circulants et infertilité.

Circulating nucleic acids (cell-free DNA and microRNAs) have for particularity to be easily detectable in the biological fluids of the body. Therefore, they constitute biomarkers of interest in female and male infertility care. Indeed, in female, they can be used to detect ovarian reserve disorders (polycystic ovary syndrome and low functional ovarian reserve) as well as to assess follicular microenvironment quality. Moreover, in men, their expression levels can vary in case of spermatogenesis abnormalities. Finally, circulating nucleic acids have also the ability to predict successfully the quality of in vitro embryo development. Their multiple contributions during assisted reproductive technology (ART) make of them biomarkers of interest, for the development of new diagnostic and/or prognostic tests, applied to our specialty. Circulating nucleic acids would so offer the possibility of personalized medical care for infertile couples in ART.

[Comparison of frozen embryo transfer outcomes at blastocyst stage according to freezing method and type of endometrial preparation]. / Comparaison des issues de transferts d'embryons congelés au stade blastocyste selon la technique de congélation et le type de préparation endométriale.

OBJECTIVE: This study intended to compare frozen embryo transfer (FET) outcomes at blastocyst stage according to freezing methods, slow freezing versus vitrification and according to the type of endometrial preparation. PATIENTS AND METHODS: A total of 172 FET at blastocyst stage (day 5 or 6) were included retrospectively from April, 2007 to December, 2012. The FET outcomes from slow freezing (group 1, n=86) were compared with those from vitrification (group 2, n=86). More particularly, the survival rate after thawing, as well as implantation and pregnancy rates (clinical and ongoing pregnancy rates) were compared respectively between these two groups, after matching on women's age at freezing day, embryo number and embryo development stage for transfer. Furthermore, for each freezing method, FET outcomes were compared according to the type of endometrial preparation, i.e. natural cycle (group N) versus stimulated cycle (group S). RESULTS: The survival rate as well as implantation and clinical pregnancy rates were significantly higher for FET after vitrification compared to FET after slow freezing (97% vs 85%, P<0.0001; 32% vs 20%, P=0.02; 43% vs 28%, P=0.04, respectively). By taking into account the number of transferred embryos for each group, the multiple pregnancy rate was three-fold higher in the group of FET after vitrification compared to the group of FET after slow freezing but not significantly (27.3% vs 8.3%, NS). However, FET outcomes were not affected significantly by the type of endometrial preparation whatever freezing methods. Nevertheless, the early spontaneous abortion (ESA) rate was lower in the case of embryos that were frozen by vitrification and transferred in natural cycle (group N2 vs group S2: 20% vs 47%, NS). DISCUSSION AND CONCLUSION: Our study confirms that the survival rate after thawing at blastocyst stage (day 5 or 6) is significantly improved after freezing by vitrification compared to slow freezing method. Likewise, implantation and clinical pregnancy rates are significantly increased in the case of FET at blastocyst stage when these embryos were frozen by vitrification. The results obtained by vitrification are very satisfactory but are also associated with an increased multiple pregnancy rate. Moreover, FET associated with natural or stimulated cycle does not modify significantly the outcomes of attempts, whatever the freezing method. However, the risk of ESA is reduced in the case of FET with natural cycle and after embryo vitrification.