Closed vitrification of human oocytes and blastocysts: outcomes from a series of clinical cases

Abstract

Purpose: High survival rates and clinical outcomes similar to those from fresh oocytes and blastocysts have been observed with open oocyte vitrification systems. It has been suggested that the extremely fast cooling rates that are only achieved with open systems are necessary for human oocyte and blastocyst vitrification. However, there is a potential risk of introducing contamination with open systems. The aim of this study was to assess whether similar survival and subsequent implantation rates could be achieved using a closed vitrification system for human oocytes and blastocysts. Methods: Initially, donated immature oocytes that were matured in vitro were vitrified using the cryoprotecta..