Day 3 v Day 5....
Basically, the hurdle between day 3 and 5 is a big one. So, statistically the embryos that make it to day 5 have a better chance of sticking. It all depends on your embryologist and clinic policy.
I think that anyone can go for a day 5 transfer, as long as they have enough viable embryos to try and make the jump, since you can lose all of them. Sometimes age can determine when you do the transfer, sometimes just egg quality can determine it, how you respond to stims, how many eggs you have...etc.
We went for a day 5 transfer, and ended up with only 4 viable blasts.
The reason it is preferred is because they do stand a better chance. Not to say that day 3 don't. Fact is, the medium they grow them in is NOT you!
So, if your embryos look like they might not make it in the medium, they will likely transfer. You are the optimum environment.
This is one of the things that our embryologist explained to us - because when you say "day 5 is better" people get very discouraged when they only make it to day 3. Getting to day 5 is a risk, sometimes day 3 embryos will do better in you, than in an artificial environment.
The odds are good with either. Day 3 is minimum, day 5 is just a little more oomph. OOur embryologist went into the details a ton with us...and we did push to day 5, on his advice, it was kind of a tense couple of days, as the medium that they put the day 3 embryos into doesn't let you see the emrbyos. So we could have walked in for the transfer on day 5 and not have had anything.http://www.embryoivf.com/embryology.html#Blastocyst
That is what my embryologist (who is a family friend, and an awesome awesome guy) wrote about it.
It is all pretty interesting stuff. Day 5 is pretty new actually, there are still a lot of clinics that don't do it.
I didn't realize that you both were in Colorado! Schoolcraft rocks - he is one of the best...my mom's fiance's twins were a result of his help.
I went to Conceptions...as I said the embryologist was a family friend, and I wanted him to do all the futzing with the eggs.
The IVF nurses there are AWESOME!