scholarly journals Investigation of methods and factors influencing mouse oocyte quality, in vitro fertilization and embryo development

2018 ◽  
Author(s):  
◽  
Liga Wuri
Keyword(s):  
In Vitro Fertilization ◽  
Clinical Outcome ◽  
Embryonic Development ◽  
Embryo Development ◽  
Biomedical Research ◽  
Oocyte Quality ◽  
Mouse Oocyte ◽  
Cortical Granules ◽  
Vitro Fertilization

Mice are one of the most commonly used rodent species as a model for biomedical research to better understand molecular, genetic, and cellular causes of human disease and disorders. The production of good quality oocytes is one of the important determinant factors for successful assisted reproductive technologies (ARTs) clinical outcome as well as reproductive biology research. Mouse oocyte quality, morphology and functions are influenced by a variety of the factors such as euthanasia methods of female donors, superovulation regimes and cryopreservation. The objectives of these studies were mainly to investigate the methods and factors that are influencing oocyte quality, in-vitro fertilization (IVF) and embryonic development. First, how different euthanasia methods including cervical dislocation (CD), high flow rate CO[2] (H CO[2]) and low flow CO2 (L CO[2]) would affect the quality and integrity of the metaphase II (MII) oocytes have been investigated. Cumulus oocyte complexes (COCs) were collected from female donors that were euthanized by three different methods and then the oocytes' subcellular structures including microtubules, F-actin, cortical granules (CGs) and mitochondria integrities were detected by specific fluorescence dyes. The results showed that L CO[2] caused significant increase in the incidence of premature cortical granule exocytosis (PCGE) which might be responsible for significantly reducing the in-vitro fertilization (IVF) and embryonic development rate compared to CD and H CO[2]. Secondly, how the superovulation methods would affect the resulting oocyte morphology, quality, IVF competence and embryonic development was investigated. The anti-inhibin serum (AIS) superovulation method produced a significantly higher number of oocytes compared to the pregnant mare serum gonadotrophin (PMSG). Overall, both methods yielded oocytes with similar sizes and comparable subcellular structures including microtubules, F-actin, cortical granules and mitochondria. However, superovulation with AIS produced significantly thinner zona pellucide than PMSG and the perivitelline space of the oocytes generated from AIS were significantly larger than PMSG. There were no differences in terms of two-cell embryo development, or morula and blastocyst formation rates between AIS and PMSG when the oocytes from two methods were in-vitro fertilized with fresh sperm. Morula and blastocyst development rates were significantly higher for AIS compared to PMSG when oocytes were fertilized with frozen-thawed sperm. Thirdly, clutches of mouse cumulus oocytes complexes (COCs) were cryopreserved by the cryoloop vitrification method after PMSG superovulation. The cryo-survival rate and integrity and distribution of subcellular structures including the meiotic spindles, F-actin, cortical granules and mitochondria were examined and compared with fresh MII oocytes. The vitrified-warmed oocytes maintained their subcellular structures to a high degree and resulted in acceptable IVF and embryonic development. In conclusion, for optimal research and clinical outcome, considerations should be given regard to euthanasia methods of oocyte donor mice and type of superovulation regimes. Despite of its high oocyte yield, superovulation of mice with AIS provides comparable quality oocytes to the PMSG method. Cryopreservation of the clutches of mouse COCs via cryo-loop vitrification should be considered for genome banking of genetically modified mice and biomedical research.

scholarly journals Fertilization, embryo development, and clinical outcome of immature oocytes obtained from natural cycle in vitro fertilization

2012 ◽  
Vol 30 (1) ◽  
pp. 43-47 ◽  
Author(s):  
Weon-Young Son ◽  
Jin-Tae Chung ◽  
Mausumi Das ◽  
William Buckett ◽  
Ezgi Demirtas ◽  
...  
Keyword(s):  
In Vitro Fertilization ◽  
Clinical Outcome ◽  
Embryo Development ◽  
Natural Cycle ◽  
Vitro Fertilization ◽  
Immature Oocytes

333 EFFECTS OF BOVINE OOCYTE QUALITY ON KINETICS OF NUCLEAR MATURATION AND EMBRYONIC DEVELOPMENT AFTER IN VITRO FERTILIZATION

2010 ◽  
Vol 22 (1) ◽  
pp. 322
Author(s):  
I. Carvalhais ◽  
M. Faheem ◽  
A. Habibi ◽  
A. Geraldo ◽  
R. Agrícola ◽  
...  
Keyword(s):  
In Vitro Fertilization ◽  
Embryonic Development ◽  
Cumulus Cells ◽  
Oocyte Quality ◽  
Blastocyst Stage ◽  
Morphological Aspect ◽  
Vitro Fertilization ◽  
Nuclear Maturation ◽  
Group I

Many factors act together to prepare the immature oocyte for successful development to a competent embryo after fertilization. Defects in oocyte maturation and further development can possibly be caused by the oocyte quality or an inadequate nuclear maturation or even by a failure of both. In the present study, the effect of COCs quality on meiotic development and further embryo-development after in vitro fertilization was evaluated. A total of 3604 COCs was separated according to their morphological aspect and were classified as A, B, and C categories. Briefly, in class A, oocytes possessed compact layers of cumulus cells, being difficult to evaluate their number having a homogenous ooplasm with uniform color. In class B, oocytes show more or equal to five layers of cumulus cells, easily identifiable under a stereomicroscope and/or granulations in the ooplasm. In class C, some granulation was observed in oocytes with about three layers of cumulus cells. The total number of oocytes was divided into two groups (I and II) in which in the group I, COCs (n = 540) were fixed 0, 6, 12, 18, 24, and 30 h following ovarian aspiration, DNA was stained with aceto-orcein, and the nucleus were observed under a phase contrast microscope. In the Group II, COCs (n = 3064) were fertilized with frozen/thawed bull semen after 24 h of maturation, which was made in M199 medium (Sigma, St, Louis, MO, USA). The development of the embryos was evaluated on the third and seventh day after fertilization. Embryos were co-cultured with monolayers of granulosa cells in 45 μL droplets of B2 medium (CCD Laboratory, Paris, France), supplemented with 10% serum under mineral oil, at 39°C and 5% CO2 in air. It was observed that, other than the oocytes achieved metaphase II at 24 h was greater for the oocytes classified as A (65.4%), and B (61.0%) greater than C (51.2%), no statistical difference was observed between oocyte quality and capability to maturation. As far as the embryonic development is concerned, the same tendency was observed for the cleavage and for the morulae/blastocyst stage after 7 days after fertilization (P < 0.001). The percentages of cleaved oocytes classified as A, B, and C, were respectively 65.2%, 58.4%, and 48.0%. The development to the morulae/blastocyst stage of the cleaved embryos was A = 38.5%/27.4%, B = 33.6%/25.0%, and C = 30.9%/17.2% (Table 1). The results of our study clearly demonstrate that the morphology of the oocytes plays an important role on the in vitro embryonic developmental competence after fertilization. Table 1.Development of oocytes according to COCs quality, evaluated 3 and 7 days after fertilization The first author is supported by the Regional Foundation for Science and Technology of the Azores Government. This study was supported by the IBBA Institute grant number M2.1.2/I/022/2008 CITA-A is fully acknowledged.

scholarly journals Effect of melatonin on the clinical outcome of patients with repeated cycles after failed cycles of in vitro fertilization and intracytoplasmic sperm injection

2021 ◽  
Author(s):  
Qi Zhu ◽  
Kaijuan Wang ◽  
Chao Zhang ◽  
Beili Chen ◽  
Huijuan Zou ◽  
...  
Keyword(s):  
In Vitro Fertilization ◽  
Clinical Outcome ◽  
Embryonic Development ◽  
Pregnancy Rate ◽  
Intracytoplasmic Sperm Injection ◽  
Clinical Pregnancy ◽  
High Quality ◽  
Vitro Fertilization ◽  
Embryo Cultures

Abstract Background: Melatonin (MT), a powerful antioxidant, can effectively ameliorate the in vitro development of animal embryos, but few studies have been performed on human embryos. Therefore, we investigated whether the application of MT in embryo cultures can improve embryonic development and clinical outcomes of patients with repeated cycles after failed in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles.Methods: Human immature oocytes from controlled ovarian hyperstimulation cycles were collected for in vitro maturation culture and ICSI fertilization. The obtained embryos were cultured in vitro in medium containing 0, 10-11, 10-9, 10-7 or 10-5 M MT, and 10-9 M was determined to be the optimal concentration. Subsequently, 140 patients who experienced failed IVF/ICSI cycles underwent 140 cycles of embryo culture in vitro with medium containing 10-9 M MT. High-quality blastocysts were collected and cryopreserved for three months before vitrified-warmed embryo transfer. These culture cycles served as the experimental (10-9 M) group. The control (0 M) group comprised previous failed cycles. The patients were further divided into subgroups of 1, 2 or ≥3 failed cycles. The fertilization and embryo development statuses were compared.Results: The fertilization, cleavage, high-quality embryo, blastocyst, and high-quality blastocyst rates of the 10-9 M group were significantly higher than those of the 0 M group (87.7% vs. 83.6%, p <0.01; 94.1% vs. 90.5%, p <0.01; 58.3% vs. 43.8%, 51.1% vs. 41.8%, 43.4% vs. 22.9%, all p <0.0001). To date, a total of 50 vitrified-warmed cycle transfers were performed in the 10-9 M group and the implantation rate, biochemical pregnancy rate and clinical pregnancy rate were significantly higher than those in the 0 M group (65.6% vs. 9.7%, p <0.0001; 64.0% vs. 12.5%, p <0.0001; 40.0% vs. 11.7%, p <0.0001). Two healthy infants were delivered successfully and the other 18 women who achieved clinical pregnancy also had good examination indexes.Conclusion: The application of MT to embryo cultures in vitro improved embryonic development in patients with repeated cycles after failed IVF/ICSI cycles and had good clinical outcomes. The optimal concentration of MT was 10-9 M.Trial registration: Name in the registry: Effect of melatonin on the clinical outcome of patients with repeated cycles after failed cycles of in vitro fertilization and intracytoplasmic sperm injection; registration number: ChiCTR2100045552; date of registration: April 19, 2021(retrospectively registered); URL of trial registry record: www.medresman.org.cn.

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