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Updated: Jan 30, 2026

Minimum Volume Vitrification of Immature Feline Oocytes
Published on: June 24, 2020
Effect of oocyte morphology on post-warming survival and embryo development in vitrified autologous oocytes
Aila Coello1, Eva Sanchez1, Begoña Vallejo1
1Instituto Valenciano de Infertilidad (IVI), University of Valencia, Pl. Policía Local 3, Valencia, Spain.
Research Question:
Does the presence of dysmorphisms affect post-warming survival and embryo development in vitrified autologous oocytes?
Design:
A retrospective study comparing post-warming survival, fertilization and embryo development between morphologically normal (n = 269) and dysmorphic oocytes (n = 147).
Results:
The survival rate was 81.4% in the morphologically normal oocytes and 87.1% in the dysmorphic oocyte group (OR 1.53; 95% CI 0.86 to 2.72). The fertilization rate was 69.9 versus 66.4% (OR 0.85; 95% CI 0.53 to 1.36), the proportion of good-quality embryos on day 3 was 30.3% versus 32.0% (OR 1.08; 95% CI 0.59 to 1.97) and the blastocyst formation rate was 54.5% versus 60.5% (OR 1.27; 95% CI 0.60 to 2.72) for the morphologically normal and the dysmorphic oocytes group, respectively. No statistical differences were found when the number and type of dysmorphism were analysed.
Conclusion:
Oocyte dysmorphisms did not seem to affect survival, fertilization and embryo development in vitrified autologous oocytes, and yielded comparable results to the morphologically normal oocytes.
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