Thanks very much for your reply felicita, and I'm so glad you managed to be so fabulously successful. It's good to know that the slower embies are definitely still viable; I just found out yesterday by letter that my second emby they told me wasn't viable at all was actually frozen on Day 6 (don't know why they didn't call me last week). So I'm going to ring them today to find out how the hell it caught up and why it was suddenly good enough to freeze!
Slow embies aren't great, but my main concern is my low fert rate. I'm going to be trying CoQ10 and such for the next three months before I do another stim (and I'll get to do an FET before then). Hopefully it might help, but who knows? The embryologist tried to tell me that 2/5 fert. wasn't too bad, and pointed out that it was actually 3/5 but the third only had 1 PN so was abnormal. Sorry, but I'm not going to count that one! In my reading anything below a 50% fert rate with ICSI is considered low, and is usually an egg issue (and would have to be in our case, as the sperm comes from Xytex in the US and is meant to go through screening for high quality).
Thanks again for sharing your story.