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Dive into the research topics where Fernando Guimarães is active.

Publication


Featured researches published by Fernando Guimarães.


Journal of Assisted Reproduction and Genetics | 2017

Freeze-all cycle for all normal responders?

Matheus Roque; Marcello Valle; Fernando Guimarães; Marcos Sampaio; Selmo Geber

PurposeThe purpose of this study is to evaluate the freeze-all strategy in subgroups of normal responders, to assess whether this strategy is beneficial regardless of ovarian response, and to evaluate the possibility of implementing an individualized embryo transfer (iET) based on ovarian response.MethodsThis was an observational, cohort study performed in a private IVF center. A total of 938 IVF cycles were included in this study. The patients were submitted to controlled ovarian stimulation (COS) with a gonadotropin-releasing hormone (GnRH) antagonist protocol and a cleavage-stage day 3 embryo transfer. We performed a comparison of outcomes between the fresh embryo transfer (n = 523) and the freeze-all cycles (n = 415). The analysis was performed in two subgroups of patients based on the number of retrieved oocytes: Group 1 (4–9 oocytes) and Group 2 (10–15 oocytes).Result(s)In Group 1 (4–9 retrieved oocytes), the implantation rates (IR) were 17.9 and 20.5% (P = 0.259) in the fresh and freeze-all group, respectively; the ongoing pregnancy rates (OPR) were 31 and 33% (P = 0.577) in the fresh and freeze-all group, respectively. In Group 2 (10–15 oocytes), the IR were 22.1 and 30.1% (P = 0.028) and the OPR were 34 and 47% (P = 0.021) in the fresh and freeze-all groups, respectively.Conclusion(s)Although the freeze-all policy may be related to better in vitro fertilization (IVF) outcomes in normal responders, these potential advantages decrease with worsening ovarian response. Patients with poorer ovarian response do not benefit from the freeze-all strategy.


JBRA assisted reproduction | 2015

Cost-Effectiveness of the Freeze-All Policy

Matheus Roque; Marcello Valle; Fernando Guimarães; Marcos Sampaio; Selmo Geber

OBJECTIVE To evaluate the cost-effectiveness of freeze-all cycles when compared to fresh embryo transfer. METHODS This was an observational study with a cost-effectiveness analysis. The analysis consisted of 530 intracytoplasmic sperm injection (ICSI) cycles in a private center in Brazil between January 2012 and December 2013. A total of 530 intracytoplasmic sperm injection (ICSI) cycles - 351 fresh embryo transfers and 179 freeze-all cycles - with a gonadotropin-releasing hormone (GnRH) antagonist protocol and day 3 embryo transfers. RESULTS The pregnancy rate was 31.1% in the fresh group and 39.7% in the freeze-all group. We performed two scenario analyses for costs. In scenario 1, we included those costs associated with the ICSI cycle (monitoring during controlled ovarian stimulation [COS], oocyte retrieval, embryo transfer, IVF laboratory, and medical costs), embryo cryopreservation of supernumerary embryos, hormone measurements during COS and endometrial priming, medication use (during COS, endometrial priming, and luteal phase support), ultrasound scan for frozen- thawed embryo transfer (FET), obstetric ultrasounds, and miscarriage. The total cost (in USD) per pregnancy was statistically lower in the freeze-all cycles (19,156.73 ± 1,732.99) when compared to the fresh cycles (23,059.72 ± 2,347.02). Even in Scenario 2, when charging all of the patients in the freeze-all group for cryopreservation (regardless of supernumerary embryos) and for FET, the fresh cycles had a statistically significant increase in treatment costs per ongoing pregnancy. CONCLUSIONS The results presented in this study suggest that the freeze-all policy is a cost-effective strategy when compared to fresh embryo transfer.


Cryobiology | 2012

Birth of normal infants after transfer of embryos that were twice vitrified/warmed at cleavage stages: Report of two cases

Marcello Valle; Fernando Guimarães; Melissa Cavagnoli; Marcos Sampaio; Selmo Geber

The role of cryopreservation in assisted reproductive technology programs has increased within the last years allowing the transfer of a limited number of embryos and the storage of the remaining for future use. The reduction in the number of transferred embryos decreases the frequency of multiple pregnancy rates and of ovarian hyperstimulation syndrome while the cumulative pregnancy rate can be maximized. Moreover, as not all embryos will survive the warming process more cleavage stage embryos are warmed to improve selection for transfer. Therefore, surplus good quality cleavage stage embryos and/or blastocysts must be re-vitrified for further transfer to achieve pregnancy. To our knowledge, there have been no reports demonstrating that human embryos can be successfully vitrified/warmed twice at the cleavage stage. Thus we report two successful pregnancies and deliveries of healthy babies after transfer of embryos that were twice vitrified/warmed at 2-4 cells stage.


JBRA assisted reproduction | 2017

Can ovarian double-stimulation in the same menstrual cycle improve IVF outcomes?

Maria Cecilia Almeida Cardoso; Alessandra Evangelista; Cassio Alessandro Paganoti Sartorio; George Queiroz Vaz; Caio Werneck; Fernando Guimarães; Paulo Gallo de Sá; Maria Cecilia Erthal

Objective To evaluate the double-stimulation protocol efficacy over conventional ovarian stimulation in recovering a more adequate number of oocytes and increase the number of embryos to be transferred or to be genetically analyzed. Methods A retrospective and comparative study with 13 patients who underwent unsuccessful in vitro fertilization (IVF) cycles with a conventional antagonist ovarian stimulation protocol and repeat the attempt with a double stimulation protocol. The following variables were analyzed: number of oocytes collected, mature oocytes collected, fertilization rate, blastocyst rate, biopsied blastocyst rate and euploidy rate. Results The double stimulation protocol had a significant higher number of oocytes collected (p=0.007) and mature oocytes to be injected (p=0.01). There was no statistically significant difference in fertilization (p=0.78) and blastocyst (p=0.59) rates. Conclusion Double stimulation favors patients who are at risk of incurring several attempts of IVF to achieve pregnancy.


JBRA assisted reproduction | 2016

Live births after polar body biopsy and frozen-thawed cleavage stage embryo transfer: case report

Fernando Guimarães; Matheus Roque; Marcello Valle; Alessandra Kostolias; Rodrigo A de Azevedo; Ciro D Martinhago; Marcos Sampaio; Selmo Geber

Pre-implantation genetic diagnosis (PGD) or screening (PGS) technology, has emerged and developed in the past few years, benefiting couples as it allows the selection and transfer of healthy embryos during IVF treatments. These techniques can be performed in oocytes (polar-body biopsy) or embryos (blastomere or trophectoderm biopsy). In this case report, we describe the first two live births to be published in Brazil after a polar-body (PB) biopsy. In case 1, a 42-year-old was submitted to PB biopsy with PGS due to advanced maternal age and poor ovarian reserve. Five MII oocytes underwent first and second polar body biopsy and four cleavage embryos were cryopreserved. The PGS analysis resulted in two euploid embryos (next generation sequence). A frozen-thawed embryo transfer (FET) was performed after endometrial priming and a healthy baby was delivered after a cesarean section (37 weeks, female, 3390g, 47.5 cm). In case 2, a 40-year old patient with balanced translocation and poor ovarian response was submitted to PB biopsy. Two MII oocytes underwent first and second polar body biopsy and two embryos were cryopreserved in cleavage stage. The analysis resulted in one euploid embryo that was transferred after endometrial priming. A preterm healthy baby (34 weeks, female, 2100g, 40 cm) was delivered via cesarean section. In conclusion, although the blastocyst biopsy is the norm when performing PGS/PGD during IVF treatments, other alternatives (as PB biopsy) should be considered in some specific situations.


Fertility and Sterility | 2015

Freeze-all policy: fresh vs. frozen-thawed embryo transfer

Matheus Roque; Marcello Valle; Fernando Guimarães; Marcos Sampaio; Selmo Geber


Journal of Assisted Reproduction and Genetics | 2012

Effects of transfer of embryos independently cultured in essential and sequential culture media on pregnancy rates in assisted reproduction cycles

Selmo Geber; Renata Bossi; Fernando Guimarães; Marcello Valle; Marcos Sampaio


Fertility and Sterility | 2016

Freeze-all policy in poor responders

Matheus Roque; Marcello Valle; Fernando Guimarães; A.F. Kostolias; Marcos Sampaio; Selmo Geber


Fertility and Sterility | 2016

Freeze-all policy in normal responders

Matheus Roque; Marcello Valle; Fernando Guimarães; A.F. Kostolias; Marcos Sampaio; Selmo Geber


Fertility and Sterility | 2014

Ratio of progesterone to number of follicles on the day of final oocyte maturation as a prognostic tool in in vitro fertilization cycles

Matheus Roque; Selmo Geber; Marcos Sampaio; Fernando Guimarães; Marcello Valle; Miguel A. Checa

Collaboration


Dive into the Fernando Guimarães's collaboration.

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Marcos Sampaio

Universidade Federal de Minas Gerais

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Selmo Geber

Universidade Federal de Minas Gerais

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Matheus Roque

Autonomous University of Barcelona

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Selmo Geber

Universidade Federal de Minas Gerais

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Alessandra Evangelista

Rio de Janeiro State University

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George Queiroz Vaz

Rio de Janeiro State University

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Matheus Roque

Autonomous University of Barcelona

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Miguel A. Checa

Autonomous University of Barcelona

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