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Is oocyte morphology prognostic of embryo developmental potential after ICSI?

https://doi.org/10.1016/S1472-6483(10)62006-8Get rights and content

Abstract

Metaphase II-stage oocytes collected from patients following ovarian stimulation show varying qualities. Both nuclear and cytoplasmic maturation have to be completed in a co-ordinated mode to ensure optimal conditions for subsequent fertilization. Disturbances or asynchrony of these processes may result in different morphological abnormalities, depending on whether nuclear or cytoplasmic maturation has been affected. In this respect it has been suggested that dysmorphic features occurring early in meiotic maturation may be associated with a higher frequency of aneuploidy and fertilization failure, while those occurring late in maturation may cause a higher incidence of developmental failure. In fact, more than half of the gametes collected show morphological abnormalities, some of which seem to be correlated with an impaired outcome (e.g. aggregation of endoplasmic reticulum, vacuolization, increased ooplasmic viscosity, giant eggs). Therefore, it is strongly recommended to include oocyte quality in all scoring systems applied in IVF laboratories.

Section snippets

Thomas Ebner, PhD, attended the Paris Lodron University of Salzburg (Austria) from 1985 to 1992, from which he graduated with honours. From 1992 until the end of 1994 he worked on his thesis in cancer research at the Institute for Pathology at the General Hospital in Salzburg. After a two-year period as a researcher at the Division of Animal Physiology of Salzburg University he began his IVF career in Linz (1997). With his post-doctoral thesis dealing with non-invasive selection at different

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    Thomas Ebner, PhD, attended the Paris Lodron University of Salzburg (Austria) from 1985 to 1992, from which he graduated with honours. From 1992 until the end of 1994 he worked on his thesis in cancer research at the Institute for Pathology at the General Hospital in Salzburg. After a two-year period as a researcher at the Division of Animal Physiology of Salzburg University he began his IVF career in Linz (1997). With his post-doctoral thesis dealing with non-invasive selection at different stages of preimplantation development, he qualified as a university lecturer in Salzburg. Thomas Ebner has published more than 50 papers in national and international journals and his research interests are non-invasive selection processes in IVF, apoptosis, and culture media.

    Paper based on contribution presented at the International Serono Symposium ‘How to improve ART outcome by gamete selection’ in Gubbio, Italy, October 7–8, 2005.

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