BACKGROUND In vitro maturation (IVM) of immature oocytes collected from ovary has been proposed for fertility preservation. In addition, quality of oocytes post IVM is one of the factors determining its developmental competence. By using the non-invasive Polscope system, both meiotic spindle (MS) and zona pellucida (ZP) can be assessed in living oocytes. OBJECTIVE The aim was to investigate t...

This study was undertaken to determine whether fully grown oocytes isolated from the early antral follicles (2-8 mm size) of frozen-thawed buffalo ovaries are viable and can be rescued to undergo maturation, fertilization, and embryo development in vitro. Ovaries were cryopreserved just after being collected during slaughter from the local abattoir using in situ oocyte (ISO) cryopreservation. I...

Background: Oocyte maturation is usually defined as the period of progression from the first to the second meiotic arrest and involves coordinated nuclear and cytoplasmic modification. Ca2+ signals are known as important regulators of oocyte maturation. Extracellular Ca2+ is important for first polar body formation, normal meiosis kinetics, and for preserving the chromosome and spindle configur...

Porcine immature oocyte quality (i.e., that of live oocytes at the germinal vesicle stage) was evaluated according to features of the surrounding cumulus, aiming to establish maturational competence of different subpopulations of such cumulus-oocyte complexes. Six subpopulations were identified: A1 (with a dense cumulus), A2 (with a translucent cumulus), B1 (with the corona radiata), B2 (partly...

For human IVF, the patient's ovaries are hormonally stimulated to ensure the collection of fully matured oocytes that are at the metaphase II stage. Only these oocytes can be successfully fertilized either when mixed with sperm or after ICSI. Nevertheless, in some cases immature or maturing oocytes are recovered from follicles. Surprisingly, sometimes these oocytes do not complete maturation wh...

We studied the effect of different storage conditions of porcine ovaries (time, temperature) on the characteristics of the follicular fluid, immature oocyte quality, meiotic competence and in vitro fertilization of oocytes. Ovaries were stored for 2, 4 or 6 h at 3 different temperatures (15 ̊C, 25 ̊C or 35 ̊C). As the storage time increased, pH and glucose concentration of the follicular fluid, pe...

OBJECTIVE Retinoids are recognized as important regulators of cell differention and tissue function. Previous studies, performed both in vivo and in vitro, indicate that retinoids influence several reproductive events. In this study, we investigated the effect of all-trans retinoic acid (t-RA) on maturation and fertilization rate of immature oocytes (germinal vesicle). MATERIALS AND METHODS G...

introduction: superovulation produces complications in some patients, so invitro maturation of oocytes is used to decrease or eliminate these complications and improve ivf. moreover, ivm is used for different aspects of reproductive researches. slaughterhouse ovaries are the main source of oocytes for ivm and ivf studies. different media has been introduced and experimented for in vitro maturat...

objective: this study evaluated in vitro maturation (ivm) of oocytes in the germinal vesicle (gv) stage in stimulated intracytoplasmic sperm injection (icsi) cycles. materials and methods: a total of 26 women, aged 18 -37 years, who were candidates for icsi at the fatemeh zahra infertility and health reproductive research center in 2007 were recruited for this study. we used the standard long p...

In Vitro Maturation (IVM) is a method that immature oocytes in antral follicles are extracted and matured in laboratry conditions. This review has attempted to provide the current knowledge and recent findings in in vitro maturation of oocytes and highlights the most important factors involved in this process. The review is based on literature reports and the author's experience. In IVM cycles,...