INTRODUCTION Despite the fact that ovarian stimulation is controlled, it is not always predictable. Because the day of human chorionic gonadotrophin (hCG) injection depends mainly on the patient's ovarian response to gonadotrophins, the day of oocyte retrieval cannot be determined in advance. As a result, oocyte retrievals are often scheduled to occur on weekends, a fact that entails at least o...

OBJECTIVE To determine the clinical potential of donor-oocyte cryopreservation and thaw techniques for recipient patients. DESIGN Institutional review board-approved prospective study of donor oocyte cryopreservation. SETTING A large, private infertility center. PATIENT(S) Four anonymous oocyte donors underwent ovarian hyperstimulation for the purpose of oocyte retrieval and cryopreservat...

BACKGROUND GJA1 and PTX3 were proposed as gene markers for oocyte and embryo developmental competence, while SERPINE2 was reported to be associated with pregnancy outcome. PRSS35, which is exclusively expressed in the ovary, may be correlated with oocyte competence. This study was conducted to evaluate the correlation of cumulus GJA1, PRSS35, PTX3, and SERPINE2 gene expression levels with oocyt...

In vitro growth of immature oocytes provides opportunities to increase gametic resources and to understand the mechanisms underlying oocyte development. Many studies on the in vitro growth of oocytes have been reported thus far; however, only a few cases have been reported, which demonstrated that oocytes can support full-term development after in vitro fertilization. Our research group recentl...

In sexually reproducing animals, the ability to coordinate oocyte maturation and sperm availability has profound effects on reproductive success. InCaenorhabditis elegans, cell–cell signaling is crucial for promoting germline development, oocyte maturation, and ovulation. In this issue of Genes & Development, Miller et al. (2003) provide new insights into the role that sperm play in oocyte matu...

background: irradiation is one of the major causes of induced sperm dna damage. various studies suggested a relation between sperm dna damage and fertilization rate after intra-cytoplasmic sperm injection (icsi). objective: in this study, fertilization rate and premature chromosome condensation (pcc) formation after icsi of hamster oocytes with irradiated sperms from normal and oligosperm indiv...

background to current knowledge, different oocyte's recovery method and various seasons have profound impact on in vitro embryo production (ivep). objectives the aim of this study was to define an efficient recovery method for oocytes harvesting from slaughterhouse material in different seasons, and their effects on ivep yield. materials and methods ovaries from slaughtered ewes in breeding sea...

OBJECTIVE We evaluated the fertilization potential of immature oocytes obtained from controlled ovarian hyperstimulation cycles of patients undergoing ICSI. METHODS We retrospectively analyzed 463 ICSI cycles containing at least one immature oocyte at oocyte denudation. ICSI was performed on mature oocytes at oocyte denudation (metaphase-II [MII] oocytes) and the oocytes that extruded the fir...

In pigs, the efficiency of embryo production after intracytoplasmic sperm injection (ICSI) is still low because of frequent failure of normal fertilization, which involves formation of two polar bodies and two pronuclei. To clarify the reasons for this, we hypothesized that ICSI does not properly trigger sperm-induced fertilization events, especially intracellular Ca2+ signaling, also known as ...

The maturation of an oocyte into an egg is a key step in preparation for fertilization. In Xenopus, oocyte maturation is independent of transcription, being regulated at the level of translation and post-translational modifications of proteins. To identify factors involved in the maturation process we used two-dimensional differential gel electrophoresis to compare the proteome of oocytes and e...