BACKGROUND Previous studies showed that immature oocytes stored in ovarian tissue could develop to the mature stage after transplantation. However, the quality and competency of the oocytes developed in xenografted ovarian tissue have never been investigated. As a pilot study to investigate this uncharted issue, we evaluated microtubule organization and chromatin configuration of human oocytes ...

A total of 82 patients underwent 106 cycles in which immature oocytes were recovered after hCG priming and transferred at blastocyst-stage. After transfer, the implantation rate was 26.8%, and the clinical pregnancy rate was 51.9%. We found that the oocytes retrieved after hCG priming in women with high risk of ovarian hyperstimulation syndrome in the in vitro maturation program can develop to ...

Cytoplasmic extracts of meiotically mature mouse oocytes were injected into immature Xenopus laevis oocytes, which underwent germinal vesicle breakdown within 2 h. Germinal vesicle breakdown was not inhibited by incubation of the Xenopus oocytes in cycloheximide (20 micrograms/ml). Identically prepared extracts of meiotically immature mouse oocytes, arrested at the germinal vesicle stage by dib...

Background: Cryobiology and in vitro maturation of oocytes are very important tools of reproductive technology. Oocyte plays an important role in fertility. The objective of this research is comparison study the effect of invitro maturation and IVF fertilization of cryopreserved oocyte with fresh oocyte in mice. Materials and Methods: For this purpose, after superovulation was performed oocytes...

Oocyte developmental competence is one of the determining factors that in?uence outcomes an IVF cycle regarding ability a female gamete to reach maturation and be fertilized. A non-invasive approach using proteomic analysis oocyte cumulus cells (CCs) can used as method predict viability could potentially function molecular predictors for program prognosis. Our study was aimed at quantifying pro...

The potential for rescuing immature oocytes from the ovaries of females of rare felid species which die or undergo medical ovariohysterectomy was evaluated. Ovaries were recovered from 13 species representing 35 individuals in good-to-poor health. Although the majority of females were 10 yr of age or older and in fair-to-poor health, a total of 846 oocytes were recovered of which 608 (71.9%) we...

Oocyte cytoplasmic maturation is influenced by the quantity of synthesized RNA and proteins accumulated and stored during growth. Transcriptional repression and degradation of transcripts occur during oocyte nuclear maturation, and prolonged transcriptional arrest might compromise RNA stores for early development. RNA quantification of key genes in oocytes might be valuable when setting up in v...

Our aim was to optimize a cryoprotectant treatment for vitrification of immature porcine cumulus-oocyte complexes (COCs). Immature COCs were vitrified either in 35% ethylene glycol (EG), 35% propylene glycol (PG) or a combination of 17.5% EG and 17.5% PG. After warming, the COCs were in vitro matured (IVM), and surviving oocytes were in vitro fertilized (IVF) and cultured. The mean survival rat...

Maintaining and restore the full developmental competence of either mature or immature oocytes after cryopreservation processes to preserve women fertility is a goal in assisted reproductive technologies (ART). This goal arises from the need of some patients to preserve their oocytes before arriving to a reproductively mature age, such as patients who need to undergo chemotherapy. Although in v...

Aim: To evaluate the developmental competence of post-thaw vitrified bovine cumulus-oocyte complexes (COCs) in vitro. Materials and Methods: A total of 129 COCs were cryopreserved using vitrification solution comprising of 15% ethylene glycol (EG) + 15% dimethyl sulfoxide (DMSO) + 0.6 M sucrose in medium TCM-199 with 10% FBS. Immediately, within a minute they are plunged into liquid nitrogen us...