Single embryo transfer in IVF?

When I went through IVF, I transferred three embryos the first time, two the second (that is all I had) and three the last time. At one point I thought I might have four embryo's and asked to transfer the fourth but was told that because of my age (28 at the time) they wouldn't let me. I know from becoming friends with someone doing IVF in the UK, they have more limits on the number of embryo's you can transfer. BBC News in the UK published the article, IVF technique 'cuts twin births' in February. They talk about cutting the number of embryo's transferred down in younger women who have a higher chance of success. When they do so, they would wait until the 5 days after the embryo is conceived which is when it would be a Blastocyst.

Yes, embryo's that reach the Blastocyst stage are usually better quality and have a better chance at survival. But from what I had learned going through IVF waiting is not always the best way to go. My clinic always did the embryo transfer three days after the embryo was conceived. Their philosophy was the embryos that had the potential to be live births would do better in their natural environment (i.e. the womb) than they would in a petri dish. Waiting can do harm to some embryos that would otherwise have a chance if transferred earlier.

I understand the need to reduce the instance of multiple births. No one wants their babies born early only to have a hard time surviving and spending weeks or months in the hospital. But I know from personal experience, I never would have felt comfortable only transferring one embryo. Especially with the high cost of IVF - financially, physically and emotionally.