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Related Experiment Video

Updated: Jun 15, 2026

Quantitative Analysis of Protein Expression to Study Lineage Specification in Mouse Preimplantation Embryos

Quantitative Analysis of Protein Expression to Study Lineage Specification in Mouse Preimplantation Embryos

Published on: February 22, 2016

Pronuclear morphology, embryo development and chromosome constitution.

Gemma Arroyo¹, Josep Santaló, Mònica Parriego

¹Reproductive Medicine Service, Department of Obstetrics, Gynecology and Reproduction, Institut Universitari Dexeus, Barcelona, Spain. gemarr@dexeus.com

Reproductive Biomedicine Online

|March 9, 2010

Summary

Pronuclear patterns do not predict embryo chromosome status in preimplantation genetic diagnosis/screening (PGD/PGS). This study found no correlation between pronuclear morphology and embryo quality or chromosomal constitution, limiting its clinical utility.

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Area of Science:

Reproductive Biology
Genetics
Embryology

Background:

Pronuclear (PN) morphology is a visual assessment of early embryo development.
Classifications by Tesarik and Scott categorize PN patterns.
The predictive value of PN patterns for embryo ploidy remains debated in assisted reproduction.

Purpose of the Study:

To evaluate the utility of pronuclear (PN) patterns, using Tesarik and Scott classifications, as predictors of embryo chromosome constitution.
To determine if PN patterns correlate with embryo quality and developmental potential in preimplantation genetic diagnosis/screening (PGD/PGS) cycles.

Main Methods:

Retrospective analysis of 331 biopsied embryos from 73 preimplantation genetic diagnosis/screening (PGD/PGS) cycles.
Assessment of pronuclear (PN) pattern, embryo quality, and chromosome constitution (normal, aneuploid, polyploid).
Statistical analysis to determine correlations between PN patterns, embryo quality, and ploidy status.

Main Results:

No significant correlation was found between pronuclear (PN) pattern and embryo quality.
While no overall differences in ploidy were seen based on embryo quality, distinctions emerged when classifying embryos as normal, aneuploid, or polyploid.
Pronuclear pattern classification did not reliably predict the embryo's chromosome constitution or developmental potential.

Conclusions:

Pronuclear (PN) patterns, according to Tesarik and Scott classifications, are not effective predictors of embryo chromosome constitution or quality in PGD/PGS.
The study concludes that PN morphology assessment is not a useful tool for predicting embryo ploidy status or developmental potential in clinical PGD/PGS programs.