BACKGROUND The zona pellucida (ZP) is an extracellular glycoprotein matrix which surrounds all mammalian oocytes. Recent data have shown the presence of four human zona genes (ZP1, ZP2, ZP3 and ZPB). The aim of the study was to determine if all four ZP proteins are expressed and present in the human. METHODS cDNA derived from human oocytes were used to amplify by PCR the four ZP genes. In add...

BACKGROUND/AIMS To observe the effects of vitrification on spindle, zona pellucida, embryonic aneuploidy and DNA injury in in vivo-maruted, in vitro-mature and immature human oocytes. METHODS Between January 2009 and February 2015, 223 immature oocytes from 450 infertile patients, and 31 in vivo-mature oocytes from 3 infertile couples were collected. Of the 223 immature oocytes, 113 were used...

BACKGROUND To discover simple biomarkers to evaluate the aging or quality of human oocytes and clinical pregnancy rates is needed. However, the association among serum α-klotho concentrations during preimplantation, the aging or quality of human oocytes and clinical pregnancy rates has not been investigated. FINDINGS The serum α-klotho concentrations during preimplantation decreased due to ag...

The object of this study was to assess functional maturation in vitro by obtaining data on the fertilization and embryonic competence of human oocytes with or without exposure to meiosis activating sterol (MAS) during maturation in vitro. Immature oocytes were either collected from unstimulated patients with polycystic ovaries (PCO) during gynaecological surgery, or were donated by patients und...

BACKGROUND During conventional in vitro maturation (IVM), oocytes undergo nuclear maturation but do not attain full cytoplasmic maturity. The present study aimed to evaluate the quality of denuded in vitro matured human oocytes (= 'rescue IVM') following a prematuration culture (PMC) in a three-dimensional (3D) co-culture system with cumulus cells. METHODS Denuded, germinal vesicle (GV) oocyt...

The use of mammalian oocytes to assess human sperm functionality could be a helpful tool with potential applications in clinical and research programs. In an attempt to develop the pig model, the aim of the present work was to study the interaction between human spermatozoa and pig oocytes at the zona pellucida (ZP), the oolemma, and the ooplasm levels. In vitro matured pig oocytes and human sp...

background: effect of seasonal changes in human reproduction has been intensively researched. some studies acknowledge influences of seasonal variation on natural conception, while others can not confirm them. the aim of this study was to investigate the effect of seasonal changes on different stages of assisted reproductive technology (art) in tehran. materials and methods: this study was carr...