Article révisé par les pairs
Résumé : A semi-quantitative and non-invasive method for scoring embryos obtained after in-vitro fertilization (IVF) has been defined, aiming at selection of embryos before transfer and at prognostic evaluation of IVF trials. Grading of embryos observed on the inverted micrclscope was essentially based on the amount of anucleate fragments expelled during early cteavage and on developmental speed. Embryos endowed with a high score were more often associated with pregnancy and in particular with the occurrence of maple pregnancy. No difference was observed between scores attributed to embryos related to ongoing, aborted or chankal pmgnades. Average embryonic scores corrrsponding to double and triple transfers differed significantly in failures as well as pregnancies. The better quality of embryos replaced in triple transfers was also apparent from the significantly higher implantation rate per embryo observed in this group. From our results, five criteria including clinical data and embryonic scores can be derived for defining a high risk of multiple pregnancy prior to transfer. It might be warranted to replace only two embryos when these conditions are fulfilled. © 1987 IRL Press Limited.