MIR and Jamie - question about Mosaicism

Do you know anything about mosaicism? Apparently it is when a cell is tested and shows up abnormal but then corrects itself in the process of growing and dividing? I heard it could be on the order of about 30% so that means that even if the embryo tested abnormal, about 30% of the time it could be normal. I think this might only happen with PGD embryos but not sure. In this case, it seems like even if you test abnormal, you may still want to transfer these, right?

MIR, in your post below, you mention lower pregnancy rates for PGD embryos. Is this because these embryos arrest before day 5? If they make it to blast and test normal, are there still reduced pregnancy rates? When you say reduced, do you mean that they have a lower rate of implantation than an untested blast?

Also, MIR, do you have an email - I have some questions about the surrogacy process.