FET Success with 4AA and 4AB Blasts? Anyone?

I've been scouring the internet looking for success stories of FET's with 4AA and 4AB blasts and am not finding any. I guess I'm trying to figure out how much the success rates decrease when the blast is a 4 instead of a 5.

Honestly I'm not finding a lot of success with FET in general. My RE assures me that people do have success, but I'm growing skeptical. I have 4 frozen 4's and 3 frozen 3's. I do not want to waste my time if they are not going to amount to anything (not that we have a lot of other options at this point). Anyway, if any of you have success stories from FET with grade 4 embryos, I would love to hear them.

Thank you to you all.

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I had one 4BB blast transferred in June and am due any day now. I go to CCRM in Colorado and my doctor there has told me they actually have better success rates with FET's rather than fresh transfers due to the hormones being out of your body from the ER. I think the bigger indicator of whether or not the FET is successful is whether or not you're transferring a chromosomally normal blast. Blasts graded a 4 can still be abnormal chromosomally, so if you have the opportunity to get them tested you might look into that. Good luck, I hope it works out wonderfully for you!

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Thanks for sharing. That really is encouraging, and congratulations to you. Good luck in the coming days. You will be in my thoughts.

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Additional question, had they done genetic testing on the embryos if you were successful? We did not do that and since they are all frozen as day 5 blasts, I think it is too late for most clinics to do the testing.

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I'm not sure about the genetic testing, but I also went to CCRM, and had a successful FET of 2 4AA blasts - and am now 19 weeks pregnant with twins. It is my understanding that the number (1, 2, 3, 4, 5) assigned to the blast is much less important than the letters that 'grade' the blast. As I understand it, the number only relates to how developed the blast is when frozen, not the quality of the blast. An "AA" and an "AB" blast is great! I think you would have every reason to be very optimistic. CCRM also told me that they have slightly better success rates with FETs with high quality blasts than with fresh transfers. Best to you!

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I have only ever had success with FET, I have never had a successful fresh transfer. My first BFP was from a 4BB blast and she is now 3 years old. My next BFP was with a 4BB as well, unfortunately that pg m/c at 6 weeks. AA and AB blasts are very good. Best of luck to you!!!

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Thank you for your encouragement. I cannot tell you how much it helps. Our RE gave us a significantly reduced % chance of success transferring 2 blasts, 4aa and 4ab, than with our fresh cycle, transferring one 5BA. I just do not understand why that is and I am trying to make sense of it. I would think our chances would go up transferring 2 blasts instead of one. Thank you for all of your replies. I am regaining hope as we speak. THANK YOU.

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My embryologist said that they aren't really keen on the 5xx blasts b/c they are a little too far ahead since they are beginning to hatch and prefer the 4's.

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I had FET on Jan 26, 4AA, just had my beta today and I got a BFP!! I am being cautious because with my first IVF and did m/c at 5 wks. I do feel a little different this time around, so as of now, I am living in the moment! Good Luck to you!! Wishing you bunches of baby dust your way!

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not personally, but those sound like high-quality blasts to me! **MENTS** I did get a BFP from a single transfer of a fresh 4AA blast and I have 3 4ABs in the freezer. Good luck!

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Congratulations on your +++++. THat is wonderful. Good thoughts.

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Ments!! I am holding one of the results of my FET! I gave birth to beautiful twin boys last month. I'm not sure what their rating was, but they were frozen at day 5 and I was told they were good quality (I agree!). We were told a lesser percentage of success but only transferred 2 because the chances of twins with a BFP were the same a's a fresh cycle (We had gotten pregnant with our fresh...twins...but I lost them at 8 weeks because of a SCH.). FETs do work!! Best of luck!!!

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This string of posts made my day!!

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Yep- I had BFNs from my 2 fresh ivfs and then finally a BFP from my FET- we put in one AB and one BA- and we have one cute little bun in the oven! Good luck!!! Hope this is it for you!!!

PS. On the day of transfer, my RE was not optimistic- apparently they didn't thaw as good as he hoped. I learned that day they don't grade embies frozen then thawed- and they didn't look anything like they did when they were fresh. My little one obviously had other plans, so remember to keep hope no matter what!!!! :))

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