One Plus One is Better than Two: An Approach Towards a Single Blastocyst Transfer Policy for All IVF Patients / Um mais um é melhor que dois: Uma abordagem pela prática da transferência de embrião único para todos os pacientes de FIV

Abstract Objective It is known that the single embryo transfer (SET) is the best choice to reduce multiples and associated risks. The practice of cryopreserving all embryos for posterior transfer has been increasingly performed for in vitro fertilization (IVF) patients at the risk of ovarian hyperstimulation syndrome or preimplantation genetic testing for aneuploidy. However, its widespread practice is still controverse. The aim of this study was to evaluate how effective is the transfer of two sequential SET procedures compared with a double embryo transfer (DET) in freeze-only cycles. Methods This retrospective study reviewed 5,156 IVF cycles performed between 2011 and 2019, and 506 cycles using own oocytes and freeze-only policy with subsequent elective frozen-thawed embryo transfers (eFET) were selected for this study. Cycles having elective SET (eSET, n = 209) comprised our study group and as control group we included cycles performed with elective DET (eDET, n = 291). In the eSET group, 57 couples who had failed in the 1st eSET had a 2nd eFET, and the estimated cumulative ongoing pregnancy rate was calculated and compared with eDET. Results After the 1st eFET, the ongoing pregnancy rates were similar between groups (eSET: 35.4% versus eDET: 38.5%; p =0.497), but the estimated cumulative ongoing pregnancy rate after a 2nd eFET in the eSET group (eSET + SET) was significantly higher (48.8%) than in the eDET group (p < 0.001). Additionally, the eSET +SET group had a 2.7% rate of multiple gestations, which is significantly lower than the eDET group, with a 30.4% rate (p < 0.001). Conclusion Our study showed the association of freeze-only strategy with until up to two consecutive frozen-thawed eSETs resulted in higher success rates than a frozenthawed DET, while drastically reducing the rate of multiple pregnancies.

Resumo Objetivo Sabe-se que a transferência de embrião único (SET) é a melhor escolha para reduzir as gestações múltiplas e riscos associados. A prática da criopreservação de todos os embriões para transferência posterior tem sido cada vez mais utilizada para fertilização in vitro (FIV), em especial quando há risco de síndrome de hiperestimulação ovariana ou realização de teste genético pré-implantacional. Entretanto, sua utilização disseminada ainda é controversa. O objetivo deste estudo foi avaliar a eficácia de duas SET sequenciais em comparação com uma transferência de embrião dupla (DET) em ciclos de FIV onde todos os embriões foram criopreservados. Métodos Neste estudo retrospectivo foram revisados 5.156 ciclos de FIV realizados entre 2011 e 2019, e 506 ciclos usando oócitos próprios e criopreservação de todos os embriões com transferências eletivas subsequentes de embriões descongelados, foram selecionados para este estudo. Ciclos com transferência eletiva de embrião único (eSET, n = 209) compuseram nosso grupo de estudo e como grupo de controle incluímos os ciclos com transferência eletiva de dois embriões (eDET, n = 291). No grupo eSET, 57 casais que falharam na 1ª tentativa de eSET tiveram uma 2ª eFET e a taxa de gravidez em curso cumulativa foi estimada para o grupo eSET e comparada com o grupo eDET. Resultados Após a 1ª eFET, as taxas de gravidez em curso foram semelhantes entre os grupos (eSET: 35,4% versus eDET: 38,5%; p = 0,497), mas a taxa de gravidez em curso cumulativa estimada após a 2ª eFET no grupo eSET (eSET + SET) foi significativamente maior (48,8%) do que no grupo eDET (p <0,001). Além disso, as taxas de gestação múltipla foram expressivamente inferiores no grupo eSET + SET (2,7%) quando comparado ao grupo eDET (30,4%; p < 0,001). Conclusão Nosso estudo mostrou que a associação das estratégias de congelamento de todos os embriões com até duas eSETs sequenciais resultou em maiores taxas de sucesso do que uma DET com embriões descongelados, além de reduzir drasticamente a ocorrência de gestações múltiplas.

Increasing rate of anti-SARS-CoV-2 antibodies between the first and second waves of COVID-19 in Sao Paulo, Brazil: A cross-sectional blood donors-based study

ABSTRACT Background: SARS-CoV-2 infections rapidly spread along with Brazilian territory with heterogeneous transmission and mortality rates, mostly depending on region and period. Investigation of SARS-CoV-2 antibodies is an important tool to understand virus circulation. Given that blood donors are a representative casuistic of a healthy population, the authors evaluated the seroprevalence of IgG and IgM COVID-19 antibodies in 2,806 blood donors from a blood bank located in São Paulo, Brazil. Methods: Aiming to evaluate viral behavior over time, the authors selected samples from blood donors who donated in June and October 2020, and February 2021. To determine whether socio-demographic features affected the seroprevalence, the authors analyzed samples from three different regions from São Paulo (capital, metropolitan and countryside regions) and evaluated predictors as gender, age, educational level, race, and use of public transportation. Results: As expected, the authors observed that seroprevalence increased over time. Seroprevalence was greater in São Paulo city compared to metropolitan and countryside regions, being smallest in the countryside. Characteristics associated with a lower percentage of antibodies were age above 50 years, higher educational level, self-declared Caucasian, and use of individual transportation. Conclusion: In conclusion, blood donors' samples proved to accurately reflect virus circulation in the healthy population.

Antibody indexes in COVID-19 convalescent plasma donors: Unanswered questions

OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is characterized by high contagiousness, as well as variable clinical manifestations and immune responses. The antibody response to SARS-CoV-2 is directly related to viral clearance and the antibodies' ability to neutralize the virus and confer long-term immunity. Nevertheless, the response can also be associated with disease severity and evolution. This study correlated the clinical characteristics of convalescent COVID-19 patients with immunoglobulin A (IgA) and IgG anti-SARS-CoV-2 antibodies. METHODS: This study included 51 COVID-19 health care professionals who were candidates for convalescent plasma donation from April to June 2020. The subjects had symptomatic COVID-19 with a polymerase chain reaction-confirmed diagnosis. We measured anti-SARS-CoV-2 IgA and IgG antibodies after symptom recovery, and the subjects were classified as having mild, moderate, or severe symptoms. RESULTS: Anti-SARS-CoV-2 antibodies were positive in most patients (90.2%). The antibody indexes for IgA and IgG did not differ significantly between patients presenting with mild or moderate symptoms. However, they were significantly higher in patients with severe symptoms. CONCLUSIONS: Our study showed an association between higher antibody indexes and severe COVID-19 cases, and several hypotheses regarding the association of the antibody dynamics and severity of the disease in SARS-CoV-2 infection have been raised, although many questions remain unanswered.

Criteria for evaluating studies at scientific medical events

Medical journals value the quality of studies. Scientific events are spaces for discussion in the face of scientific advances, innovation and consensus. In them, space is opened for the presentation of clinical studies, translational studies, experience reports and videos, with the best-designed studies being selected and awarded. The lack of clear criteria allows for differences in assessments, making it difficult to place value on situations associated with research. In order to improve quality, it is necessary to evaluate ethics, the hierarchy of scientific evidence (methodology), the study design, the originality, the relevance, and the linearity of the material presented. The present study aims to discuss these points, presenting proposals to be used in the evaluation of clinical studies, translational studies, case reports and videos in scientific medical events.