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Updated: May 12, 2026
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Modified MicroSecure Vitrification: A Safe, Simple and Highly Effective Cryopreservation Procedure for Human Blastocysts
Published on: March 2, 2017
Open versus closed oocyte vitrification system: a prospective randomized sibling-oocyte study
A Papatheodorou1, P Vanderzwalmen, Y Panagiotidis
1IANENTRO Fertility Center, Thessaloniki, Greece. achilleas@iakentro.gr
Reproductive Biomedicine Online
|April 23, 2013
Summary
Closed system vitrification offers an aseptic alternative for oocyte cryopreservation, demonstrating comparable clinical outcomes to open systems. This method ensures oocyte viability and successful pregnancy rates without compromising results.
Area of Science:
- Reproductive Biology
- Cryobiology
- In Vitro Fertilization
Background:
- Vitrification is a key technique for oocyte and embryo cryopreservation.
- Both direct (open) and indirect (closed) systems exist for vitrification.
- Limited data exists on closed system oocyte vitrification compared to open systems.
Purpose of the Study:
- To evaluate the effectiveness of a closed, aseptic vitrification system for oocyte cryopreservation.
- To compare clinical outcomes between closed and open vitrification methods.
- To validate the closed system as a viable alternative for oocyte cryopreservation.
Main Methods:
- Prospective, randomized study design.
- Sibling oocytes from the same donor were assigned to either closed or open vitrification groups.
- 75 vitrification-warming cycles were conducted per group.
Main Results:
- Survival rates differed significantly (82.9% closed vs. 91.0% open, P<0.05).
- No significant differences were found in pregnancy, clinical pregnancy, implantation, ongoing pregnancy, or live birth rates.
- 27 healthy babies were born from the closed group and 18 from the open group.
Conclusions:
- Closed system vitrification is an effective and aseptic method for oocyte cryopreservation.
- The closed system yields comparable clinical pregnancy and implantation rates to the open system.
- This study validates the closed system as a safe alternative for oocyte cryopreservation.
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