Time filter

Source Type

Los Angeles, CA, United States

Schiewe M.C.,Ovagen Fertility | Zozula S.,Ovagen Fertility | Anderson R.E.,Ovagen Fertility | Anderson R.E.,Southern California Center for Reproductive Medicine | Fahy G.M.,21st Century Medicine
Cryobiology | Year: 2015

A novel, aseptic closed system vitrification (VTF) technique for the cryopreservation of embryos and oocytes has been developed and clinically validated in this study. It combines the practicality of embryo-containing sterile flexipettes stored safely and securely with 0.3ml CBS™ embryo straws possessing weld seals. The cooling and warming rates of this double container system were determined using a data logger. Upon direct plunging into LN2, the flexipettes cool at an average rate of 1391°C/min, while warming occurs at an average rate of 6233°C/min in a 37°C 0.5M sucrose bath. Direct deposition of the flexipette into a warming bath insured a rapid transition between -100 and -60°C to minimize potentially harmful recrystalization associated with devitrification. In conclusion, the μS-VTF system has exhibited higher (p<0.05) intact survival, implantation and live birth rates than conventional slow freezing methods. The effective embryo transfer of vitrified blastocysts proved similar to or better than fresh embryo transfer outcomes. The sustained clinical use of μS-VTF has justified a change in our infertility practice.Capsule: The microSecure vitrification (μS-VTF) procedure is a low-cost, non-commercial, aseptic, closed system that offers technical simplicity and repeatability, while effectively attaining an estimated 4:1 warming-to-cooling rate ratio, which supports excellent embryo survival and sustained viability. © 2015 The Authors. Source

Schiewe M.C.,Ovagen Fertility | Rothman C.,California Cryobank CCB | Rothman C.,Center for Male Reproduction and Vasectomy Reversal | Spitz A.,University of California at Irvine | And 3 more authors.
Journal of Assisted Reproduction and Genetics | Year: 2016

Purpose: The aim of our paper was to validate a testicular biopsy procedure that simplifies handling, processing, and cryopreservation, while at the same time optimizes sperm motility before freezing and after thawing. Methods: Two prospective studies were conducted to verify, optimize, and understand the virtues of pre-freeze testicular tissue IVC at different temperatures (21, 30, or 37 °C). Testicular tissue was obtained from clinical specimens designated for whole tissue cryopreservation (i.e., intact mass of tubules) and/or for fresh use in IVF-ICSI cycles. Whole testicular biopsy pieces (1–3 mm3) were diluted in glycerol containing freeze solutions, slow cooled to 4 °C and then rapidly frozen in LN2 vapor. Fresh and post-thaw testicular biopsy tissue were evaluated for changes in the quantity (%) and pattern of motility (I–IV: twitching to rapid progression, respectively) over a 1 week duration. The clinical effectiveness of IVC-cryopreserved whole testicular biopsy tissue was also validated analyzing fresh embryo transfers. Results: More reliable recovery of motile testicular sperm was achieved using whole tissue freeze preservation combined with IVC (24–96 h) post-acquisition at an incubation temperature of 30 °C compared to ambient temperature (21 °C) or 37 °C. Up to 85 % of the pre-freeze motility was conserved post-thaw (+3 h) for easy ICSI selection. Sperm longevity was optimized to fresh tissue levels by implementing testicular biopsy sucrose dilution post-thaw. Favorable clinical outcomes were proven using frozen-thawed testicular biopsy sperm for ICSI. Conclusions: By employing minimal tissue manipulation, integrating pre-freeze IVC processing at 30 °C and the freezing of whole testicular biopsy tissue, we have reduced the labor and improved the efficacy of processing testicular tissue for freeze-preservation and subsequent ICSI use. © 2016 The Author(s) Source

Discover hidden collaborations