Originally Posted by
nuthinbutpink
If you used day 3 FISH, you only tested chromosomes 13, 18 and 21. That still leaves 20 other chromosomes that may have an issue and FISH only looks to see if they exist. It doesn't look at the gene level so even though 18 was there, 18 could have had an issue on one or more of the genes that make up that chromosome which would caused an early loss. Hard to say why but most likely she was abnormal in some way.
You had a pretty big attrition from fertilization to day 3. I would not want to use the same protocol/meds next time because I don't think that is normal.
It IS normal for numbers to decrease from day 3 to day 5 so you will have fewer embryos to biopsy than you would on day 3 but it's generally because they are abnomral and die off naturally.
And about FISH on day 5. You cannot do FISH testing on day 5. FISH is only done on individual cells on day 3 and by day 5 the cells are strating to merge and FISH would show all abnormal results so a more advanced test is needed.
I don't know how much day 5 testing they do nor do I know how many FETs they do. I would ask if they use vitrification to freeze. If they do, it should freeze and thaw well especially if you are freezing a blast.