Abstract
Research question
Can Gardner embryo grades be converted to numeric interval variables to improve the
incorporation of embryo grading in statistical analyses?
Design
An equation that can be used to convert Gardner embryo grades to regular interval
scale variables was developed: the numerical embryo quality scoring index (NEQsi).
The NEQsi system was then validated with a retrospective chart analysis assessing
IVF cycles (n = 1711) conducted at a single Canadian fertility centre between 2014 and 2022. Gardner
embryo grades on file were assigned using EmbryoScope and converted to NEQsi scores.
Descriptive statistics, univariate logistic regressions and generalized estimating
equations with cycle outcomes were prepared to demonstrate the relationship between
NEQsi score and probability of pregnancy.
Results
NEQsi produces interval numerical scores that range from 2 to 11. Patient case files
in which single embryo transfers occurred (n = 1711) were examined and the Gardner embryo grades on file were converted to NEQsi
scores. NEQsi scores ranged from 3 to 11, with a median score of 9. A positive linear
relationship existed between the NEQsi scores and the probability of pregnancy (as
assessed by quantitative β-HCG). THe NEQsi score was a significant predictor of pregnancy
(P < 0.001).
Conclusion
Gardner embryo grades can be converted to interval variables and used directly statistical
analyses.
KEYWORDS
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Biography
Hannah Pierson earned her PhD in biochemistry and completed her post-doctoral fellowship in epithelial cell biology at the Johns Hopkins Medical Institute. She is a Senior Scientist with Synergyne ART Analytics Inc. Her research interests include advancing the boundaries of biomedical image interpretation technologies and the cellular dynamics of endometrium.
Key message
The Gardner embryo grading system provides insight into morphologic embryo quality. Alphanumeric grading, however, presents challenges in statistical analyses. The numerical embryo quality scoring index (NEQsi) facilitated conversion of embryo grades to interval variables for statistical purposes. A positive linear relationship was observed between NEQsi scores and probability of pregnancy.
Article info
Publication history
Published online: January 12, 2023
Accepted:
January 8,
2023
Received in revised form:
December 22,
2022
Received:
August 19,
2022
Declaration: HP and JI are employees of Synergyne Imaging Technology, Inc. JM is Laboratory Director and Chief Embryologist and an employee of TRIO Fertility Centre. RAP is Distinguished Professor of Obstetrics and Gynecology at the University of Saskatchewan and President and CSO at Synergyne Imaging Technology, Inc.Publication stage
In Press Journal Pre-ProofIdentification
Copyright
© 2023 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
