Dr Smith replies to Tangeroo:
You're right that it can never be "scientifically proven" that embryos which failed to develop in vitro might have continued in vivo (in the uterus). However, when embryos that failed to develop in vitro are analyzed for genetic abnormalities, a very high percentage had gross genetic abnormalities strongly suggesting that they were of limited devleopmental potential.
With regard to the article from Boston IVF, they same author recently gave a lecture on this subject to our local ART group (New York Society for Reproductive Medicine) and concluded that since their lab (performing in excess of 2000 cycles per year) had difficulty in growing embryos to the blastocyst stage AND since insurance reimbursement was the same for day 3 and day 5 culture of embryos, its better and more profitable to transfer on day 3. He also mentioned that you usually have some embryos to freeze on day 3, so you could charge for that too. Get the picture.
Avoiding high order multiple pregnancies is a real benefit of blastocyst transfer. However, you are correct that the jury is still out as to whether or not pregnancy rates are higher with blastocyst stage embryo transfer. Pregnancy rates depend on many things besides the stage at which the embryos are transferred (i.e. the skill of the RE in performing the embryo transfer). What is VERY clear is that the implantation rate for blastocysts is 2-3x higher than day 3 embryos.
I believe that in time, as more physicians get used to the idea of culturing embryos to the blastocyst stage prior to transfer, blastocyst transfers will become routine. You see, I remember in the early nineties there was a great discussion associated with extending embryo culture from 2 days to 3 days. When the benefits became well known and accepted, day 3 transfers became the norm. I think the same will happen again with day 5 transfers.
The paper on sequential embryo transfer (day 3 followed by day 5) is BS. You were right to be skeptical.
For your upcoming cycle, I believe that you should stick with day 5. HOWEVER, I'm a firm believer in assisted hatching (for everyone) and think this might be the key in your case. I perform assisted hatching on all blastocyst stage embryos a few hours prior to transfer.
This is a tricky protocol that few people know or perform, so have the embryologist at your program e-mail me for the protocol. We saw a jump in our pregnancy rate when I started hatching blastocysts prior to transfer, so I know it works. I also hatch all frozen-thawed blastocyst stage embryos prior to transfer.
Read how Tangeroo's discusion with Dr. T. ends....