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Updated: Jun 20, 2026

Preparation of Meiotic Chromosome Spreads from Mouse Oocytes for Assessment of Synapsis and Recombination
Published on: July 18, 2025
A case report supporting the concept that some women have a predisposition for maternal meiosis errors resulting in
J H Check1, B Katsoff, D Summers-Chase
1The University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School at Camden, Cooper Hospital/University Medical Center, Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology & Infertility, Camden, NJ, USA. laurie@ccivf.com
Purpose:
To determine if a primary aborter with recurrent miscarriage times three with her only two fetal products that were evaluated with chromosome analysis demonstrating triploidy in both fetuses could have a predisposition for maternal meiosis errors.
Methods:
In vitro fertilization with intracytoplasmic sperm injection was performed. Embryo biopsy was performed on 3-day old embryos and a single blastomere was evaluated by fluorescent in situ hybridization (FISH). Embryo transfer would be performed on day 5 at the blastocyst stage.
Results:
There were six normal and seven abnormal embryos. One of the seven was a tetraploid embryo (92XXXX).
Conclusions:
The majority of triploidies are related to polyspermy but this factor was excluded by performing ICSI. Thus this woman showed a marked predisposition to digyny. Though the tetraploidy could be explained by fertilization of a digynic egg by a diploid sperm the probability was that in this instance the meiosis error extended back to failure to extrude the first polar body.
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