PGD on IVF-derived human embryos prior to transfer into the mother's uterus is a routine procedure. There are lots of normal healthy children running around who had one cell plucked at this stage. And some who had a cell plucked, and were then frozen for future use, because there were too many normal embryos to safely transfer into the mother at one time, and then thawed and transferred later.
Thanks for the info. I also saw that this group earlier (in January) published an article addressing this.
Preimplantation Genetic Diagnosis and Human Implantation—A Review
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Reduction of multiples and frozen embryos PGD of aneuploidy may also help reduce the number of multiple pregnancies. In the two latest studies involving a test and a control group, significantly fewer embryos were trans- ferred in the PGD groups than in control groups (Gianaroli et al., 1999; Munné et al., 1999, 2003; Werlin et al., 2003). In addition, because many embryos are abnormal, after PGD there are fewer chromosomally normal embryos remain- ing in excess of those for replacement. Therefore there are very few embryos freezable, which will alleviate the problem of accumulating, storing and eventually disposing of unwanted frozen embryos