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Updated: May 25, 2026
12:11
Analysis of Chromosome Segregation, Histone Acetylation, and Spindle Morphology in Horse Oocytes
Published on: May 11, 2017
Intra-age, intercenter, and intercycle differences in chromosome abnormalities in oocytes.
Santiago Munné1, Karsten R Held, Cristina M Magli
1Reprogenetics, Livingston, New Jersey, USA. munne@reprogenetics.com
Fertility and Sterility
|February 14, 2012
Summary
Oocyte aneuploidy rates show significant variation within age groups and between fertility centers. This variability complicates predicting euploid egg yield for individual patients, impacting fertility preservation strategies.
Area of Science:
- Reproductive biology
- Human genetics
- Assisted reproductive technology
Background:
- Oocyte aneuploidy, a major cause of implantation failure and miscarriage, exhibits variability.
- Understanding variations in oocyte chromosome normality is crucial for effective in vitro fertilization (IVF) and fertility preservation.
Purpose of the Study:
- To quantify intra-age and intercycle variations in first polar body aneuploidy.
- To assess the frequency of oocyte aneuploidy in two consecutive IVF cycles within one year for the same patient.
Main Methods:
- Retrospective analysis of data from infertile couples undergoing IVF.
- Two consecutive cycles of preimplantation genetic screening (PGS) using first polar body biopsy.
- Analysis of meiosis I aneuploidy rates.
Main Results:
- Wide intra-age variations in oocyte euploidy rates (0-100%) were observed across all age groups.
- Significant differences in euploidy rates were found between fertility centers (48% vs. 25%).
- Substantial intercycle variations in euploidy for individual patients were noted, though most (68.5%) had minimal differences (±2 euploid eggs).
Conclusions:
- Oocyte aneuploidy exhibits high intra-age and intercenter variability, challenging predictions of euploid egg availability.
- Average euploidy rates decline with maternal age, but individual variation is significant.
- Current fertility preservation protocols relying solely on maternal age for egg freezing may be insufficient due to unpredictable euploid egg yield.
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