Related Experiment Video
Updated: Jun 8, 2026
Vitrification of In Vitro Matured Oocytes Collected from Adult and Prepubertal Ovaries in Sheep
Published on: July 10, 2021
Ultrastructural evaluation of human metaphase II oocytes after vitrification: closed versus open devices
Antonella Bonetti1, Marta Cervi, Francesco Tomei
1Department of Medical Morphological Research, Medical School, University of Udine, Udine, Italy.
Objective:
To compare the ultrastructural appearance of oocytes after vitrification and warming with two different devices.
Design:
Oocytes were examined by ultrastructural analysis after vitrification and warming with use of closed (CryoTip; Irvine Scientific, Santa Ana, CA) or open (Cryotop; Kitazato BioPharma Co., Ltd., Shizuoka, Japan) devices.
Setting:
Pordenone Hospital IVF Unit and Medical Morphological Research Department, University of Udine.
Patient(S):
Surplus oocytes from 10 patients (aged 31-39 years) undergoing assisted reproductive technologies at the Pathophysiology Unit of Human Reproduction and Sperm Bank between 2006 and 2008.
Intervention(S):
Oocytes with normal invertoscopic appearance underwent vitrification and warming with closed (CryoTip) or open (Cryotop) devices and were processed for transmission electron microscopy.
Main Outcome Measure(S):
Cryodamage extent and cell alterations in oocytes after open or closed vitrification and warming procedures and their rehydration rate.
Result(S):
A higher rate of complete oocyte rehydration and less-severe ultrastructural alterations were observed after vitrification and warming with the open Cryotop device.
Conclusion(S):
These preliminary data suggest that oocyte ultrastructure is better preserved with an open rather than closed vitrification and warming protocol.
