Progestin-Primed Ovarian Stimulation is a non-inferior alternative to the GnRH Antagonist Protocol in patients undergoing assisted reproductive techniques: a retrospective study.

OBJECTIVE: To demonstrate the non-inferiority of Clinical Pregnancy Rates from Progestin-Primed Ovarian Stimulation compared to the GnRH Antagonist Protocol when the freeze-all and blastocyst transfer strategy is applied. METHODS: A retrospective study included all IVF cycles performed at Pró-Criar Reproductive Medicine Center, Belo Horizonte, Minas Gerais, Brazil, between May 2018 and May 2019 using a GnRH antagonist analogue or oral progestins to block the LH peak in IVF/intra-cytoplasmic sperm injection (ICSI) cycles for infertility treatment. RESULTS: The primary outcome of our study was Clinical Pregnancy Rate at the first ET (Blastocyst), which were 58.4% in the progestin group and 54.9% in the antagonist group (p=0.735), a finding consistent with most studies published to date using different progestins. The mean number of retrieved oocytes was 11 in the antagonist group and 9 oocytes in the progestin group (p=0.009). The fertilization rate was 80% for both groups (p=0.935). The rate of blastocyst formation per cycle was 50% in the antagonist group and 55.6% in the progestin group (p=0.106). The stimulation lasted a mean of 10 days in the two groups (p=0.403) and did not vary with patient age in either group. The gonadotropin dose used was higher in the antagonist group (2025 IU) than in the progestin group (1950 IU) (p=0.057). In addition, the blockade was effective: there was only one case of spontaneous ovulation, which corresponded to less than 1% of the cycles. CONCLUSIONS: Progestin-Primed Ovarian Stimulation is a non-inferior alternative to the GnRH Antagonist Protocol in patients undergoing assisted reproductive techniques. An incidence compatible with the 0.34 to 8% risk described in the literature for failure to control the premature LH surge in antagonist protocol cycles.

Oocyte cryopreservation for future fertility: comparison of ovarian response between cancer and non-cancer patients.

OBJECTIVE: This study aimed to assess whether a diagnosis of cancer interferes with ovarian function prior to the treatment of the disease. METHODS: This observational retrospective study used data from medical records of ovarian stimulation cycles performed for purposes of oocyte cryopreservation. RESULTS: The included patients had a mean age of 35.13±3.72 years and 51.6% of them were aged between 36 and 40 years. More than half of the patients (57.6%) were single and 82.1% had a normal body mass index (BMI). Most women had not become pregnant (85.5%) or had babies (95.1%) or miscarriages (89.6%) prior to cryopreservation. The mean number of oocytes obtained from non-cancer patients was 11.4±8, while for cancer patients the number was 13.8±9. The mean number of frozen mature oocytes was 9.7±7 for the non-cancer group and 11.2±7.2 for the cancer group. The majority (63.1%) of the patients had up to 10 oocytes frozen per cycle. Breast cancer had the highest incidence among the included patients. There was no significant difference in ovarian response between patients with different types of cancer. CONCLUSION: The number of harvested and frozen oocytes from cancer and non-cancer patients indicated that in the two groups response to ovarian stimulation was similar.

Follicle Viability after Vitrification of Bovine Ovarian Tissue / Viabilidade folicular após a vitrificação de tecido ovariano bovino

Abstract Purpose The present study aimed to evaluate the impact of vitrification on the viability of follicles using a three-dimensional (3D) in vitro culture. Methods Bovine ovarian tissue samples (n = 5) obtained from slaughterhouses were utilized. The cortex was cut into small fragments of 2 x 3 x 0.5 mm using a tissue slicer. From these fragments, secondary follicles were first isolated by mechanical and enzymatic methods, then encapsulated in alginate gel and individually cultured for 20 days. Additional fragments of the same ovarian tissue were vitrified in a solution containing 25% glycerol and 25% ethylene glycol. After warming, the follicles underwent the same follicular isolation process that was performed for the fresh follicles. Results A total of 61 follicles were isolated, 51 from fresh ovarian tissue, and 10 from vitrified tissue. After the culture, the vitrified and fresh follicles showed 20% and 43.1% survival rates respectively (p = 0.290),with no significant differences. At the end of the culture, therewere no significant differences in follicular diameter between the vitrified (422.93 ± 85.05 μm) and fresh (412.99 ± 102.55 μm) groups (p = 0.725). Fresh follicles showed higher mean rate of antrum formation when compared with vitrified follicles (47.1% and 20.0% respectively), but without significant difference (p = 0.167). Conclusions The follicles were able to develop, grow and form antrum in the 3D system after vitrification, despite the lower results obtained with the fresh tissue.

Resumo Objetivo O presente estudo teve como objetivo avaliar o impacto da vitrificação na viabilidade dos folículos utilizando a cultura in vitro tridimensional (3D). Métodos Foi utilizado tecido ovariano bovino (n = 5) obtido de abatedouros. O córtex foi cortado em pequenos fragmentos de 2 x 3 x 0,5 mm, utilizando o tissue slicer e a partir destes fragmentos foram isolados folículos secundários por meio de método enzimático e mecânico, encapsulados em gel de alginato e cultivados individualmente durante 20 dias. Outros fragmentos do mesmo tecido ovariano foram vitrificados em solução contendo 25% de glicerol e 25% de etilenoglicol. Após aquecimento, os folículos passaram pelo mesmo processo de isolamento folicular realizado a fresco. Resultados Foram isolados 61 folículos, sendo 51 originários de tecido ovariano a fresco, e 10 de tecido vitrificado. Após a cultura, os folículos vitrificados apresentaram taxa de sobrevida de 20%, e o grupo a fresco apresentou taxa de 43,1% (p = 0,290). O diâmetro folicular ao final da cultura também não apresentou diferença significativa entre o grupo vitrificado (422,93 ± 85,05 μm) e a fresco (412,99 ± 102,55 μm) (p = 0,725). Os folículos a fresco apresentarammaior taxa média de formação de antro do que os folículos vitrificados (47,1% e 20,0%, respectivamente), mas sem diferença significativa (p = 0,167). Conclusões Os folículos foram capazes de se desenvolver, crescer e formar antro em sistema 3D após a vitrificação.

Follicle Viability after Vitrification of Bovine Ovarian Tissue.

Purpose The present study aimed to evaluate the impact of vitrification on the viability of follicles using a three-dimensional (3D) in vitro culture. Methods Bovine ovarian tissue samples (n = 5) obtained from slaughterhouses were utilized. The cortex was cut into small fragments of 2 × 3 × 0.5 mm using a tissue slicer. From these fragments, secondary follicles were first isolated by mechanical and enzymatic methods, then encapsulated in alginate gel and individually cultured for 20 days. Additional fragments of the same ovarian tissue were vitrified in a solution containing 25% glycerol and 25% ethylene glycol. After warming, the follicles underwent the same follicular isolation process that was performed for the fresh follicles. Results A total of 61 follicles were isolated, 51 from fresh ovarian tissue, and 10 from vitrified tissue. After the culture, the vitrified and fresh follicles showed 20% and 43.1% survival rates respectively (p = 0.290), with no significant differences. At the end of the culture, there were no significant differences in follicular diameter between the vitrified (422.93 ± 85.05 µm) and fresh (412.99 ± 102.55 µm) groups (p = 0.725). Fresh follicles showed higher mean rate of antrum formation when compared with vitrified follicles (47.1% and 20.0% respectively), but without significant difference (p = 0.167). Conclusions The follicles were able to develop, grow and form antrum in the 3D system after vitrification, despite the lower results obtained with the fresh tissue.

Objetivo O presente estudo teve como objetivo avaliar o impacto da vitrificação na viabilidade dos folículos utilizando a cultura in vitro tridimensional (3D). Métodos Foi utilizado tecido ovariano bovino (n = 5) obtido de abatedouros. O córtex foi cortado em pequenos fragmentos de 2 × 3 × 0,5 mm, utilizando o tissue slicer e a partir destes fragmentos foram isolados folículos secundários por meio de método enzimático e mecânico, encapsulados em gel de alginato e cultivados individualmente durante 20 dias. Outros fragmentos do mesmo tecido ovariano foram vitrificados em solução contendo 25% de glicerol e 25% de etilenoglicol. Após aquecimento, os folículos passaram pelo mesmo processo de isolamento folicular realizado a fresco. Resultados Foram isolados 61 folículos, sendo 51 originários de tecido ovariano a fresco, e 10 de tecido vitrificado. Após a cultura, os folículos vitrificados apresentaram taxa de sobrevida de 20%, e o grupo a fresco apresentou taxa de 43,1% (p = 0,290). O diâmetro folicular ao final da cultura também não apresentou diferença significativa entre o grupo vitrificado (422,93 ± 85,05 µm) e a fresco (412,99 ± 102,55 µm) (p = 0,725). Os folículos a fresco apresentaram maior taxa média de formação de antro do que os folículos vitrificados (47,1% e 20,0%, respectivamente), mas sem diferença significativa (p = 0,167). Conclusões Os folículos foram capazes de se desenvolver, crescer e formar antro em sistema 3D após a vitrificação.

Comparison between Slow Freezing and Vitrification in Terms of Ovarian Tissue Viability in a Bovine Model.

Objective To assess the viability of bovine ovarian tissue after cryopreservation through either slow freezing or vitrification, and to compare it to that of control tissue by performing morphological analyses. Methods The study included 20 bovine ovarian cortex fragments that were divided into control, vitrification, and slow freezing groups. Each group consisted of four fragments of the same ovary, two fixed without cultivation, and two fixed with cultivation. Tissues were evaluated based on follicular morphology immediately after heating and after 7 days of culture, and compared with the control group. Results A total of 240 fragments were analyzed, generating a sample of 1,344 follicles without cultivation and 552 with cultivation. When the non-cultivated samples were classified as non-atretic follicles, 572 were found in the control group, 289 in the vitrification group, and 373 in the slow freezing group, showing no significant differences. When classified as atretic, 46 follicles were found in the control group, 23 in the vitrification group, and 41 in the slow freezing group, also showing no statistical difference. In the post-culture sample, an evolution of the follicular stages could be observed. This finding was important to support that the follicles considered non-atretic in the non-cultivated group were actually viable in the morphological evaluation. Conclusion With no differences between the protocols, vitrification was shown to be an advanced and alternative method for patients who will undergo treatments that carry the risk of ovarian failure, as the method is less expensive, faster, and more adaptable to laboratory routine.

Comparison between Slow Freezing and Vitrification in Terms of Ovarian Tissue Viability in a Bovine Model / Comparação da viabilidade do tecido ovariano após congelamento lento e vitrificação em modelo bovino

Abstract Objective To assess the viability of bovine ovarian tissue after cryopreservation through either slow freezing or vitrification, and to compare it to that of control tissue by performing morphological analyses. Methods The study included 20 bovine ovarian cortex fragments that were divided into control, vitrification, and slow freezing groups. Each group consisted of four fragments of the same ovary, two fixed without cultivation, and two fixed with cultivation. Tissues were evaluated based on follicular morphology immediately after heating and after 7 days of culture, and compared with the control group. Results A total of 240 fragments were analyzed, generating a sample of 1,344 follicles without cultivation and 552 with cultivation. When the non-cultivated samples were classified as non-atretic follicles, 572 were found in the control group, 289 in the vitrification group, and 373 in the slow freezing group, showing no significant differences. When classified as atretic, 46 follicles were found in the control group, 23 in the vitrification group, and 41 in the slow freezing group, also showing no statistical difference. In the post-culture sample, an evolution of the follicular stages could be observed. This finding was important to support that the follicles considered non-atretic in the non-cultivated group were actually viable in the morphological evaluation. Conclusion With no differences between the protocols, vitrification was shown to be an advanced and alternative method for patients who will undergo treatments that.

Resumo Objetivo avaliar a viabilidade do tecido ovariano bovino após a criopreservação, utilizando congelamento lento e vitrificação, e comparando com o tecido controle por meio de análises morfológicas. Métodos o estudo incluiufragmentos de córtex de vinte ovários bovinos divididos em grupos controle, vitrificação e congelamento lento. Cada grupo foi composto por quatro fragmentos do mesmo ovário, sendo dois fragmentos fixados sem cultivo e dois fragmentos fixados pós-cultivo. Os tecidos foram avaliados pela morfologia folicular logo após o aquecimento e após sete dias de cultivo, e comparados com o grupo controle. Resultados um total de 240 fragmentos foi analisado, gerando uma amostra de 1.344 folículos sem cultivo e 552 pós-cultivo. Quando a amostra sem cultivo teve seus folículos agrupados em não atrésicos, obtivemos 572 no grupo controle, 289 no vitrificação, e 373 no congelamento lento, não apresentando diferença estatística. Quando agrupados em atrésicos, o grupo controle apresentou 46 folículos, o vitrificação, 23, e o congelamento lento, 41, não apresentando também diferença estatística. Na amostra pós-cultivo, podemos observar uma evolução dos estágios foliculares: esse achado foi importante para sustentar que os folículos considerados não atrésicos na avaliação morfológica sem cultivo estavam realmente viáveis. Conclusão não havendo diferenças entre os protocolos, a vitrificação se mostra um avanço e um método alternativo para pacientes que irão se submeter a tratamentos que podem levar a uma falência ovariana, uma vez que a metodologia é mais barata, mais rápida e mais bem adaptável a uma rotina de um laboratório.