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Updated: Jun 24, 2026
08:46
Fertility Preservation Through Oocyte Vitrification: Clinical and Laboratory Perspectives
Published on: September 16, 2021
Impact of oocyte cryopreservation on embryo development
M Cristina Magli1, Michela Lappi, Anna P Ferraretti
1Reproductive Medicine Unit, Società Italiana Studi Medicina della Riproduzione, Bologna, Italy.
Fertility and Sterility
|April 4, 2009
Summary
Oocyte cryopreservation impacts embryo development. Thawed oocytes show lower fertilization and cleavage rates compared to fresh oocytes, affecting embryo quality and transfer success.
Area of Science:
- Reproductive Medicine
- Embryology
- Cryobiology
Background:
- Oocyte cryopreservation is a key technique in assisted reproductive technology.
- Evaluating developmental potential of thawed oocytes is crucial for treatment success.
Purpose of the Study:
- To assess if zygote and embryo morphology from thawed oocytes predict developmental performance.
- To compare developmental outcomes of fresh versus frozen sibling oocytes.
Main Methods:
- Intracytoplasmic sperm injection (ICSI) was performed on both fresh and cryopreserved sibling oocytes.
- Compared fertilization rates, zygote morphology, and embryo cleavage rates.
- Analyzed outcomes from 997 thawed oocytes across 256 cycles.
Main Results:
- Thawed oocytes exhibited significantly lower fertilization and cleavage rates than fresh oocytes.
- Embryos from thawed oocytes had reduced development into top-quality zygotes and regularly cleaving embryos.
- Lower rates of embryo transfer and top-quality embryo transfer were observed in frozen oocyte cycles.
Conclusions:
- Slow freezing negatively impacts oocyte developmental potential, evident in early cleavage stages.
- Morphological assessment of zygotes and embryos from thawed oocytes provides relevant information on developmental performance.
- Cryopreservation affects oocyte viability and subsequent embryo development, necessitating careful evaluation.
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