Quantitative Morphometrical Characterization of Human Pronuclear Zygotes
A. Beuchat, P. Thévenaz, M. Unser, T. Ebner, A. Senn, F. Urner, M. Germond, C.O.S. Sorzano
Human Reproduction, vol. 23, no. 9, pp. 1983–1992, September 2008.
BACKGROUND: Identification of embryos with high implantation potential remains a challenge in in vitro fertilization (IVF). Subjective pronuclear (PN) zygote scoring systems have been developed for that purpose. The aim of this work was to provide a software tool that enables objective measuring of morphological characteristics of the human PN zygote. METHODS: A computer program was created to analyse zygote images semi-automatically, providing precise morphological measurements. The accuracy of this approach was first validated by comparing zygotes from two different IVF centres with computer-assisted measurements or subjective scoring. Computer-assisted measurement and subjective scoring were then compared for their ability to classify zygotes with high and low implantation probability by using a linear discriminant analysis. RESULTS: Zygote images coming from the two IVF centres were analysed with the software, resulting in a series of precise measurements of 24 variables. Using subjective scoring, the cytoplasmic halo was the only feature which was significantly different between the two IVF centres. Computer-assisted measurements revealed significant differences between centres in PN centring, PN proximity, cytoplasmic halo and features related to nucleolar precursor bodies distribution. The zygote classification error achieved with the computer-assisted measurements (0.363) was slightly inferior to that of the subjective ones (0.393). CONCLUSIONS: A precise and objective characterization of the morphology of human PN zygotes can be achieved by the use of an advanced image analysis tool. This computer-assisted analysis allows for a better morphological characterization of human zygotes and can be used for classification.
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@ARTICLE(http://bigwww.epfl.ch/publications/beuchat0801.html,
AUTHOR="Beuchat, A. and Th{\'{e}}venaz, P. and Unser, M. and Ebner, T.
and Senn, A. and Urner, F. and Germond, M. and Sorzano,
C.{\'{O}}.S.",
TITLE="Quantitative Morphometrical Characterization of Human Pronuclear
Zygotes",
JOURNAL="Human Reproduction",
YEAR="2008",
volume="23",
number="9",
pages="1983--1992",
month="September",
note="")