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Published on: February 22, 2016
Intra- and inter-observer analysis in the morphological assessment of early-stage embryos
Goedele Paternot1, Johanna Devroe, Sophie Debrock
1Leuven University Fertility Centre, UZ Leuven, Campus Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium. goedele.paternot@uzleuven.be
Background:
The aim of this study was to determine the intra- and inter-observer variability in the evaluation of embryo quality. Multilevel images of embryos on day 1, day 2 and day 3, were analysed using different morphological parameters.
Methods:
Multilevel images of embryos on day 1, day 2 and day 3, were analysed using a standard scoring system. The kappa coefficient was calculated to measure intra- and inter-observer variability before and after training sessions.
Results:
Good to excellent intra-observer agreement was present for most parameters exceptions being scoring the position of pronuclei and the presence of a cytoplasmic halo on day 1, multinucleation on day 2 and the size of fragments on day 3. Inter-observer agreement was only good to excellent for the number of blastomeres on day 2 and day 3 and the orientation of the cleavage axes on day 2. Training sessions had a positive impact on inter-observer agreement.
Conclusion:
In conclusion, assessment of morphological characteristics of early stage embryos using multilevel images was marked by a high intra-observer and a moderate inter-observer agreement. Training sessions were useful to increase inter-observer agreement.
