BACKGROUND Recent studies have demonstrated that morphology of the first polar body (1(st)PB) is related to oocyte viability, which can be used as a prognostic tool to predict oocyte performance and pregnancy outcomes in an intracytoplasmic sperm injection (ICSI) program. According to some studies, there is a correlation between oocyte performance and 1(st)PB morphology, while others have not r...

Objective(s): Failed fertilization after intra-cytoplasmic sperm injection (ICSI) is mainly attributed to failed oocyte activation and can be overcome by artificial oocyte activation (AOA). The present study aims to compare in vitro outcomes of ICSI following two different assisted oocyte activation chemical procedures (SrCl2 and Ionomycin) in sibling oocytes of ICSI candidates.Materials and Me...

BACKGROUND Although irregularities in human zona pellucida (ZP) morphology are well described, there is scant literature on the clinical significance of ZP dysmorphology. We, therefore, designed a retrospective cohort trial of ZP dysmorphology to assess the clinical significance of ZP dysmorphology and its affect on IVF outcome. Over the same time period a random sample of 77 cycles of 77 subje...

Objective: To assess the influence of MII oocyte morphology on the fertilization outcome and embryo development in ART cycles. Since, age may affect the quality of oocyte, the role of women's age was also evaluated following IVF or ICSI cycles. Materials and Methods: 200 MII oocytes from 30 IVF and ICSI cycles were evaluated. The morphology of oocytes that were fertilized in IVF cycles (IVF+) w...

Citrinin is one of the mycotoxins and has been shown to have various toxic effects in animals and humans. Although previous study showed the toxic effects of citrinin on the female reproductive system, especially on oocyte maturation, however, the causes or mechanism of citrinin on oocyte quality is unclear. In present study we deeply investigated this topic. We found thatcitrinin toxin exposur...

Obesity was shown to cause reproductive dysfunctions such as reduced conception, infertility and early pregnancy loss. However, the possible effects of obesity on oocyte quality are still not fully understood. In this study we investigated the effects of both diet and gene mutation induced obesity on impairments in mouse oocyte polarization, oxidative stress, and epigenetic modifications. Our r...

BACKGROUND A successful oocyte cryopreservation programme is of utmost importance where a limited number of oocytes can be inseminated per cycle, to overcome legal and ethical issues related to embryo storage, for oocyte donation programmes and for fertility preservation (especially for cancer patients). Vitrification has been recently proposed as an effective procedure for this purpose. METH...

We hypothesized that oocyte morphology may be associated with the accumulation of specific mRNAs encoding proteins responsible for the gamete fertilization ability. Therefore, the aim of the study was to evaluate the transcript levels of porcine zona pellucida (pZP1, pZP2, pZP3 and pZP4) glycoproteins in oocytes classified by a four-grade morphological scale (I-IV) accounting for either a homog...

In prepuberal mouse ovaries oocytes in the non-growing pool show constant but low levels of DNA-dependent RNA polymerase activity. The first event in the initiation of oocyte growth is a marked stimulation of RNA polymerase activity in the oocyte nucleolus. This is followed by increases in oocyte area, oocyte nucleolar area, oocyte nuclear area and nucleoplasmic RNA synthesis in that sequence. ...