Human embryo chromosomes: preliminary results of a study to karyotype multipronuclear human oocytes fertilized in vitro.

Using special techniques the authors have analyzed the chromosome constitution of human gametes participating in fertilization in vitro. Only oocytes with multiple pronuclei have been used in this study. Two conclusions are reached by the Authors: first, that the gametes involved in the production of oocytes with multiple pronuclei can be chromosomally abnormal, specifically aneuploid and that not all oocytes with three pronuclei will cleave to form triploid embryos. The Authors underline that even normal, normospermically fertilized oocytes could have a chromosomal abnormality. They conclude that embryos with chromosomal abnormalities may be produced by IVF and ET and that their existence is reflected by the inability of the vast majority of transferred embryos to survive to term delivery.