BACKGROUND Sperm vitrification is a technique of ice and cryoprotectant free cryopreservation by direct plunging of sperm suspension into liquid nitrogen (LN2). The aim of this study was to investigate the influence of cryoprotectant free-vitrification on human sperm fine structure by MSOME technology and the fertility potential by zona binding assay (ZBA). METHODS 20 normo-ejaculates were pr...

The vitrification of a liquid occurs when ice crystal formation is prevented in the cryogenic environment through ultrarapid cooling. In general, vitrification entails a large temperature difference between the liquid and its surrounding medium. In our droplet vitrification experiments, we observed that such vitrification events are accompanied by a Leidenfrost phenomenon, which impedes the hea...

Sir, In the challenging paper by Wang et al. (2008), the authors have reported about an effective method of vitrification of human ovarian tissue with direct contact of cells in liquid nitrogen, named needle immersed vitrification. Childbirth after cryopreservation of ovarian tissue is now a reality (Donnez et al., 2004; Demeestere et al., 2007; Meirow et al., 2007; Andersen et al., 2008) and t...

Clinical embryo vitrification evolved with the development of unique vitrification devices in the 21st century and with the misconception that ultra-rapid cooling in an "open" system (i.e., direct LN2 contact) was a necessity to optimize vitrification success. The dogma surrounding the importance of cooling rates led to unsafe practices subject to technical variation and to the creation of vitr...

BACKGROUND The aim of this study was to compare the viability of human pronuclear oocytes subjected to vitrification using cooling by direct submerging of open-pulled straws in liquid nitrogen versus vitrification by cooling of open-pulled straws located inside a closed 0.5 ml straw (aseptic system). METHODS Two- and three-pronuclei stage oocytes (n=114) were cryopreserved in super-open-pulle...

Gamete cryopreservation combined with in vitro embryo production (IVP) and cryopreservation of resultant embryos are important technologies for gene banking in domestic animals. Especially, cryopreservation of embryos and oocytes offers the possibility for the preservation of female genetic lines. Although several vitrification protocols have been developed for the cryopreservation of embryos a...

BACKGROUND Vitrification is now a commonly applied technique for cryopreservation in assisted reproductive technology (ART) replacing, in many cases, conventional slow cooling methodology. This review examines evidence relevant to comparison of the two approaches applied to human oocytes and embryos at different developmental stages. METHODS Critical review of the published literature using P...

In this study the efficacy of the combination of glycerol (GLY) and ethylene glycol (EG) as cryoprotectants in a vitrification method developed for direct embryo transfer was evaluated by in vitro development of in vitro fertilized (IVF) and somatic cell nuclear transfer (SCNT) embryos after vitrification. The IVF and SCNT blastocysts were vitrified in either 40% GLY, 30% GLY + 10% EG, or 20% G...

As early as 1985, ice-free cryopreservation of mouse embryos at -196 degrees C by vitrification was reported in an attempted alternative approach to cryostorage. Since then, vitrification techniques have entered more and more the mainstream of animal reproduction as an alternative cryopreservation method to traditional slow-cooling/rapid-thaw protocols. In addition, the last few years have seen...

This study was performed to evaluate the efficiency of simplified EM grid vitrification, skipping the step of removing the cryoprotectant (5.5M EG + 1.0M sucrose) droplet on the grid after loading oocytes, compared to conventional cryopreservation protocols for mouse mature oocytes. Firstly, the recovery, survival, fertilization and hatching rates of simplified EM grid vitrification were compar...