Abstract: P-172

Effect of Vitrification (VTF) Device System and Solution on Postwarming Viability of Re-Vitrified Human Blastocysts: A Randomized Cross Over Study.

Presenter: Mitchel Schiewe


Abstract


OBJECTIVE: We have shown that human blastocysts (BL) are resilient to re-vitrification (rVTF) up to 5 times using microSecure (µS) VTF, as well as extended room temperature exposure up to 10 min in 3 different commercial VTF solutions (30% EG/DMSO; 32% EG/PPG and >7.9M Glycerol (G)/EG). The purpose of this investigation was to better understand the interrelationship between cryophysical and chemical factors on the efficacy of BL-VTF. view more

OBJECTIVE: We have shown that human blastocysts (BL) are resilient to re-vitrification (rVTF) up to 5 times using microSecure (µS) VTF, as well as extended room temperature exposure up to 10 min in 3 different commercial VTF solutions (30% EG/DMSO; 32% EG/PPG and >7.9M Glycerol (G)/EG). The purpose of this investigation was to better understand the interrelationship between cryophysical and chemical factors on the efficacy of BL-VTF.
DESIGN: Research consented BL (N=164) in 2 laboratories (Lab 1 and Lab 2) were randomly assigned to a 2x2 factorial design: closed/µS-VTF (used by Lab 1) and open-Cryolock (CL; used by Lab 2) devices, and G/EG (I.C.E.; Lab 1) or EG/DMSO (15%/15%; made in Lab 2) cryoprotective solutions. Up to 2 BL were vitrified per device (n=41/treatment group) and then rewarmed for viability determination. Differences in survival percentage and 24h development was statistically compared by Chi-squared analysis (p<0.05).
MATERIALS AND METHODS: Vitrified BL (≥3BB quality) were subjected to standard, rapid µS (Lab 1) or CL (Lab 2) warming and then cultured in Global medium (LifeGlobal) under tri-gas, humidified conditions (37oC). Upon equilibration (<2h), BL were randomly assigned to a rVTF treatment group. All BL were then vitrified using a standard device-solution VTF protocol, and subsequently warmed accordingly, re-equilibrated and cultured for 24h. Assessment of embryo survival was performed at 0h, 2h, and 24h (i.e., continued development) post-warming for all treatment groups.
RESULTS: When comparing device-solution treatments, significantly fewer EG/DMSO embryos survived in µS devices, while both crossover treatments exhibited equally reduced 24h development (see Table). Overall, there was a technical signature observed between Labs, as more (p<0.05) BL developed in Lab 1 (66/80; 82.5%) in contrast to Lab 2 (54/84; 64.3%).

VTF device x solution: CLxEG/DMSO Lab 1/Lab 2 CLxG/EG Lab 1/Lab 2 µSxEG/DMSO Lab 1/Lab 2 µSxG/EG Lab 1/Lab 2
# Warmed
Total #
20 / 21
41
20 / 21
41
20 / 21
41
20 / 21
41
0-2 h Survival
Total # (%)
20 / 21
41(100%)a
20 / 17
37(90.2%)ab
20 / 13
33(80.5%)c
20 / 16
36(87.8%)bc
24h Development
Total # (%)
17 / 20
37(90.2%) a
14 / 11
25(61%)c
17 / 8
25(61%)c
18 / 15
33(80.5%)b





a,b,c Column values with different superscripts within rows are different(p<0.05)
CONCLUSIONS: Lab 2 technician familiarity and experience with the µS-VTF system and G/EG solutions may have had an effect, while Lab 1 staff had more proficiency with their crossover treatments (i.e., CL and EG/DMSO use). Alternatively, the observed results may be correlated to the lack of resiliency by DMSO-exposed BL to rVTF under different conditions, as the Lab 2 control group did excel. More investigation is needed to explain why CLxG/EG-treated BL exhibited significant damage. Additional trials and increased sample sizes are needed to fully discern the treatment effects of differential vitrification exposures and device systems.

show less

Share this PosterTalk

About PosterTalks

PosterTalks allows meeting attendees the ability to view these presentations, download or bookmark their favorite presentations, download PDF versions of the posters, ask questions, leave comments, and share presentations with their colleagues – all from the convenience of a smart phone.

Contact Us

Have a question? Click here to contact us. Need technical support? Click here to email support.

© 2018 PosterTalks and Connect BioMed. All other content and data, including data entered into this website are copyrighted by their respective owners.