BACKGROUND As embryo selection is not allowed by law in Switzerland, we need a single early scoring system to identify zygotes with high implantation potential and to select zygotes for fresh transfer or cryopreservation. The underlying aim is to maximize the cumulated pregnancy rate while limiting the number of multiple pregnancies. METHODS In all, 613 fresh and 617 frozen-thawed zygotes wer...

This study was undertaken to compare the efficiency of fresh and frozen-thawed buck semen on in vitro fertilization (IVF) of goat oocytes. Cumulus oocytes complexes (COCs) were collected by aspiration of 2-6 mm diameter follicles, which were obtained from slaughterhouse. Upon grading, only normal quality COCs were maturated in TCM-199 for 48 hours. The percentage of COCs reached to the M-II sta...

This study was designed to investigate the dynamics of the paternal genome demethylation in pronuclear-stage bovine zygotes produced either by in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) using freeze-thawed (FT) as well as freeze-dried (FD) bull sperm stored at +4 or -196 C for one year. Zygotes were fixed and immunostained using anti-5-methyl-cytosin at 8, 10, 14 an...

In mammals fertilization triggers a series of Ca(2+) oscillations that not only are essential for events of egg activation but also stimulate oxidative phosphorylation. Little is known, however, about the relationship between quantitative changes in egg metabolism and specific long-term effects in offspring. This study assessed whether post-natal growth is modulated by early transient changes i...

BACKGROUND The in vitro culture of presumed zygotes derived from single cow ovum pick-up (OPU) is important for the production of quality blastocysts maintaining pedigree. The aim of the present study was to evaluate the agar chip-embedded helper embryo coculture system for single cow OPU-derived zygotes by assessing embryo quality. METHODS Cumulus oocyte complexes (COCs) were collected from ...

One difficulty in analyzing the damage response is that the effect of damage itself and that of cellular response are hard to distinguish in irradiated cells. In mouse zygotes, damage can be introduced by irradiated sperm, while damage response can be studied in the unirradiated maternal pronucleus. We have analyzed the p53-dependent damage responses in irradiated-sperm mouse zygotes and found ...

Abstract Study question Do morphometric and morphokinetic profiles of pronuclei (PN) following intracytoplasmic sperm injection (ICSI) vary between male female human zygotes? Summary answer Male zygotes displayed different PN morphometrics morphokinetics. Additionally, variations were identified sperm-originated (SPN) oocyte-originated (OPN) pronuclei. What is known already Previous studies hav...

Supernumerary pronucleated stage oocytes (PN) are usually cryopreserved. PN are transferred in spontaneous, stimulated or artificial cycles. In this study, an artificial cycle with a transdermal therapeutic system was used for oestradiol release (Estraderm TTS 100) in combination with a targeted drug delivery system for vaginal progesterone release (Crinone 8%). Patients started transdermal 17b...

Trisomy 16, the 45,X monosomy and triploidy are the more frequent chromosome anomalies in spontaneous abortions. Earlier estimations, based on frequencies of diandric triploidy at conception, resulted in a good correlation with the frequencies of diploid sperm in infertile males (up to 1.9%). Recent data have shown that most diandric triploids originate by dispermy, although 8.3% of them are pr...