I am new here, and was searching through some old posts about CGH, and would like to share our experience with it in case it helps anyone. We had a proven donor (25 years old), and had 8 "perfect-looking" five day blasts tested. Of those 8, only 3 came back normal. I am really surprised by it, and remember our RE saying CGH "usually doesn't turn up much" with donors. As someone who had enough OE m/cs, I wanted to go forward with the testing, and I am glad I did. I read about 60% of DE embryos are normal by CGH, and ours is more around 40% - I just never would have guessed based on the donor's prior cycles.
Have a call with a genetics counselor later in the week to answer questions, but very perplexed right now!