Morphological evaluation of blastocyst after vitrification depending on treatment modality

Sammanfattning: Assisted reproductive technology procedures has become a more complex treatment over the years after implementation of preimplantation genetic diagnostics and cryopreservation methods such as slow freeze and vitrification. When embryos undergo these methods they are exposed to external damage that threaten to affect their quality and thereby lead to lower survival rates and lower pregnancy rates. The aim of this study was to document blastocysts quality after vitrification, re-vitrification and preimplantation genetic diagnosis with subsequent vitrification. A total of 126 blastocysts were collected, of which 119 blastocysts were documented with the help of an experienced embryologists and the remaining seven blastocysts were from a new series of re-vitrified embryos. The 126 collected blastocyst were allocated into groups depending on their degree of preimplantation genetic diagnosis and vitrification. The gathered data was scoring according to morphology, expansion and proportion of necrotic cells at 2 and 4 hours of the expansion phase. Fisher exact test was used for statistical evaluation. There were no significant difference when comparing data before and after vitrification and preimplantation diagnosis, which indicates that these methods do not cause morphological damage to the blastocyst.