# bit confused



## cjsx2 (Sep 5, 2010)

i had 2 embryos put in 4cell and 7cell, what determines embryologist to put embryos to blastocyst? its my 2nd attempt nat fet and both neg, just wondered if next time i could ask them to do it?


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## karenanna (Dec 27, 2008)

Sorry to hear about your BFNs     

Blastocyst transfers are only usually used when you have more than 5 embryos at day 3 (each clinic has a different policy on the exact number) and it is difficult to tell which are in the lead - by culturing them a bit longer they can see which are the better embryos by day 5. If you only have a couple of embryos or it is very clear on day 2 or 3 which are the strongest then they are better inside you and there is no advantage to a blastocyst transfer.

Hope this helps

Karenanna xxx


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