The purpose of this retrospective study was to establish a prognosis for implantation, pregnancy and live birth rates in stimulated IVF cycles after transferring embryos derived from: 1/ retrieved immature oocytes that matured overnight in vitro (late mature group: LM); 2/ retrieved immature oocytes that matured overnight in vitro and were added to the embryos derived from retrieved mature oocy...

Amphibian eggs normally require meiotic maturation to be competent for fertilization. A necessary prerequisite for this event is sperm binding, and we show that under normal physiological conditions this property is acquired at, but not before, meiotic maturation. Immature oocytes do not bind sperm, but injection of total egg poly(A)+ mRNA into immature oocytes confers sperm binding in the abse...

The aim of this study was to evaluate the effect of sperm cryopreservation and the maturation state of the oocyte on the time course of canine gamete interaction during co-culture for periods of 1-10 h. Semen samples were obtained by digital stimulation and ejaculates processed as fresh, chilled and frozen samples. Sperm were co-cultured with immature or in vitro mature bitch oocytes for up to ...

•We reported oocyte collection from an ovarian tumor with a single ovary.•Intra-operative retrieval of oocytes may be useful for preserving fertility.•We have done in vitro maturation for immature oocytes with ovarian enucleation.

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 ...

Background: The pregnancy rates from oocytes matured in vitro are much lower than those of in vivo stimulation cycles, indicating that optimization of IVM remains a challenge. Reduced developmental competence of oocytes matured in vitro indicates that current culture systems for oocytes maturation do not adequately support nuclear and/or cytoplasmic maturation. Therefore in this study, we evalu...

Background The utilization of immature oocytes derived from stimulated cycles could be of great importance, specially for urgent fertility preservation cases. The aim of the current study was to determine whether in-vitro maturation is more successful before or after the vitrification of these oocytes. MaterialsAndMethods The study was performed in a private IVF center. 318 germinal vesicle (GV...

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...

Abstract Compared to somatic or sperm cells, mammalian oocytes are much more sensitive cryopreservation mainly because of the large volume, cytoskeleton, and presence zona pellucida. Connections with surrounding cumulus cells also challenging preserve in immature oocytes. Besides genetic epigenetic information enclosed nucleus, contain organelles cytoplasmic factors that necessary for early emb...