This also depends on the lab and the couple. Each couple has a different number of embryos to test as each woman has a different number of oocytes collected and a different development of embryos so it depends on the couple, their history, their reproductive potential and on the capacity of the lab to keep the standards of the lab procedure at a high level. Actually there is not a straight number for PGTA testing. You can test from one to how many embryos you need to test. Of course when you test more than three or four blastocysts then you have a chance of having a normal one. It is good to check more than three to four blastocysts because then you have a chance of finding a normal one to transfer back to the uterus.
