during spring, summer and winter seasons, sistani donor cows, with normal reproductive status, were superovulated and embryos were recovered non-surgically on day 7. grade a blastocyst embryos were either transferred fresh (spring) or frozen (summer and winter). recovered embryos during summer and winter were exposed to glycerol and frozen using conventional method. during spring season, recipi...

Production of high quality embryos in vitro needs an efficient in vitro fertilization (IVF). Seminal origin is one of the important factors that affects the success of in vitro embryo production. So our goal was to determine the effect of using fresh and frozen semen in fertilization on developmental competence and cryo-survival of buffalo embryos. Buffalo oocytes wer...

introduction: mouse embryos can successfully be frozen with sucrose and propandiol. however, different developmental stages of mammalian embryos have shown to have various capacities to undergo freeze-thawing procedure. in the present study, the ability of 1,2,4 and 8-ell mouse embryo to tolerate the freeze-thawing procedure was investigated and the effect of this procedure on the further in vi...

During spring, summer and winter seasons, Sistani donor cows, with normal reproductive status, were superovulated and embryos were recovered non-surgically on day 7. Grade A blastocyst embryos were either transferred fresh (spring) or frozen (summer and winter). Recovered embryos during summer and winter were exposed to glycerol and frozen using conventional method. During spring season, recipi...

The use of cryopreserved human embryos in gene expression studies provides an additional source to the scarce embryos available for research. To validate their use we have implemented a quantitative RT-PCR to characterize the levels of the tuberous sclerosis, TSC2 gene in fresh and frozen-thawed human embryos. Frozen embryos were thawed using two different clinical protocols. In fresh embryos 9...

background: the purpose of the study was to compare clinical pregnancy and delivery rates with fresh and frozen embryo transfer in patients admitted to shiraz- human assisted reproductive center with ovarian hyperstimulation syndrome (ohss). methods: ohss patients randomly divided in two groups, group a (n=50) with fresh embryo transfer and group b (n=50) with frozen embryo transfer. we used vi...

BACKGROUND Morphometric and morphokinetic evaluation of in vitro cultured human embryos allows evaluation without time restriction and reduces intra- and inter-observer variability. Even though these technologies have been reported to improve the quality of cleavage stage embryo evaluation during fresh culture, possible advantages in the evaluation of cryopreserved embryos have been scarcely ex...

the use of donated embryos has offered hope for infertile couples who have no other means to have children. in iran, fertility centers use fertile couples as embryo donors. in this paper, the advantages and disadvantages of this procedure will be discussed. we conclude that embryo-donation should be performed with frozen embryos thus preventing healthy donors from being harmed by fertility drug...