BACKGROUND Nitric oxide (NO) is a cell messenger with multiple actions in different biological systems, implicated in the control of follicle and oocyte function. NO is formed from L-arginine by isoforms of nitric oxide synthase (NOS) via NG-hydroxy-L-arginine, with L-citrulline as a byproduct. This study aimed to show how modulation of NO by manipulating NOS substrates would affect mouse folli...

Structural changes in the ovaries of WBB6F1-Sl/Slt mutant mice aged 10, 25, 35, and 60 days and 7 months were studied light and electron microscopically. Neither secondary nor Graafian follicles could be found in any of the animals studied, and only primary follicles were usually seen until 35 days. In most follicles, the oocyte was lost. The hyperplastic proliferation of follicle epithelial ce...

BACKGROUND Several global studies have assessed maternal and perinatal outcomes and complications with the type of embryo transfer (ET) following in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). The present study assessed the incidence of maternal and perinatal outcomes and complications following IVF/ICSI associated with the type of embryo transferred. METHODOLOGY A total ...

Vertebrate female reproduction is limited by the oocyte stockpiles acquired during embryonic development. These are gradually depleted over the organism's lifetime through the process of apoptosis. The timer that triggers this cell death is yet to be identified. We used the Xenopus egg/oocyte system to examine the hypothesis that nutrient stores can regulate oocyte viability. We show that pento...

Genetic experiments suggest that polarization of the oocyte is linked directly to the initial cell fate determination that singles out the oocyte from its 15 sister cells. Specification of oocyte cell fate as well as establishment and maintenance of a polarized microtubule network within the Drosophila oocyte require the activity of the egalitarian (egl) and BicaudalD (BicD) genes. We have isol...

BACKGROUND Polycystic ovary syndrome (PCOS) is a common endocrine disorder of unknown pathology, involving reproductive and metabolic abnormalities. Oocyte-specific genes are a group of genes expressed exclusively in ovarian tissue; therefore, they can play an important role in ovarian pathologies such as PCOS. The zona pellucida 4 (ZP4) gene encodes glycoprotein which is a part of the extracel...

OBJECTIVE To determine the extent of intra-age and intercycle variations in the frequency of first polar body aneuploidy in two consecutive cycles of oocyte retrieval undertaken by the same patient within 1 year. DESIGN Retrospective study. SETTING Fertility centers. PATIENT(S) Infertile couples undergoing IVF. INTERVENTION(S) Patients underwent two consecutive cycles of preimplantation...

The objective of this review was to examine the role of the various spermatozoal components suspected of actively participating in early human development. The contributions of the fertilizing spermatozoon to the oocyte include, as a minimum, the delivery of the DNA/chromatin, a putative oocyte-activating factor (OAF), and a centriole. Recent data indicate that spermatozoa may also provide the ...

BACKGROUND Gene expression profiling of normal receptive endometrium has been characterized, but intrinsic defects in endometrial gene expression associated with implantation failure have not been reported. METHODS Women who had previously participated as recipients in oocyte donation cycles and repeatedly exhibited implantation failure (Group A, study group) or had at least one successful cy...

Cryopreservation of mature oocytes and embryos has provided numerous benefits in reproductive medicine. Although successful cryopreservation of germinal-vesicle stage (GV) oocytes holds promise for further advances in reproductive biology and clinical embryology fields, reports regarding cryopreservation of immature oocytes are limited. Oocyte survival and maturation rates have improved since v...