FET - on which day is ET with blastocysts?

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Natalie Anne
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Joined: Wed May 05, 2004 9:29 am
Location: Cheshire

FET - on which day is ET with blastocysts?

Post by Natalie Anne » Fri Jan 26, 2007 12:17 pm


we are preparing for our 8th attempt and have decided to let 5 of our frozen embryos be thawed and left for 5 days to go to blastocyst stage before embryo transfer.

when i've had FET in the past, ET day has always been day 18. For blastocyst transfer, will they keep me on the oestrogen and do the ET on a later day or do they just thaw them earlier and still do ET on day 18?

i forgot to ask this at my appointment.

many thanks
9 failed attempts using thawed, surgically retrieved sperm.
2 year break and vasectomy reversal for dh.
Consultation for 10th attempt using fresh sperm - Nov 09.


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Post by beachbaby » Fri Jan 26, 2007 1:15 pm

Hi Natalie, welcome, unfortunately i cannot help you i am currently preparing for my second FET but my transfers are day 2 embryo's, but my cycle is drug controlled by the clinic so times can vary, I think if you are using a natural cycle then your transfer will be later. ie: if day 18 was a transfer for 2 day old embryo's then a 5 day blast would be fransferred on day21. i beleive thats correct but not 100% sure. I wish you all the best in this cycle, you are very strong to have been through this so many times.Good luck
Me 39, DH 40. TTC 5years
4th times a charm,1-IVF, 3xFET's, 2 chemical
Twin boys born 9/7/08

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Post by sassynlv » Fri Jan 26, 2007 2:24 pm

Natalie: i am also doing a blast FET right now. My frosties were frozed at 2pn. They started thawing them on Sunday, and apparently Mon was considered the completion of day 2. I was scheduled for my FET on Thursday, which would have been considered day 5 for the embryos (my cd 19). due to slow growth, it has been postponed to today. i don't know if that is what you are asking... but i hope it helped. and good luck!
6 fresh IVFs plus one cancelation
Last Chance FET--- Pregnant with triplets!

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Post by Ghost » Fri Jan 26, 2007 3:02 pm

Beachbaby's answer is correct at every clinic I know of. In an FET cycle, the ET day is adjusted to conform with the embryo's stage of development, in order to mimic the natural schedule. The endometrium and embryos need to be on the same schedule. There is a little more flexibility in an FET (the endometrium is more precisely controlled in FET than in stimulated cycles because you don't have all those follicles producing hormones), but the natural cycle is the model to aim for.

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Post by Kate21 » Fri Jan 26, 2007 8:10 pm

Hi Natalie,
I'm due to do a FET with blasto's this month. When I spoke to my clinic they said ET would be 6 days after ovulation (as long as the lining and everything is all ok). Hope that helps?

Me 35 DH 44 unexplained infertility
3# IVF all BFN
3# FET all BFN 4# BFP - no heartbeat @7wks - about to start the journey again!!

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Post by skidoo » Sun Jan 28, 2007 10:16 pm

Sorry I can not answer your question. I was on a medicated cycle, they thawed 3 zygotes on Monday and they all developed to blasts by Friday. They placed all of them back in on Friday Jan 26th.

I was a little confused as how do they really know the right time to put them back in??? I guess they know their business better than I.

Good luck to all of you!
9/05 Clomid M/C Boy 19 wks 1/06
8/06 IUI BFN
11/06 1st IVF BFN
1/07 FET BFP Its a BOY!!!
Lukas Born Oct 8 2007 8lb 15 oz

Natalie Anne
Posts: 195
Joined: Wed May 05, 2004 9:29 am
Location: Cheshire

Post by Natalie Anne » Wed Jan 31, 2007 12:15 pm

many thanks for your replies ladies, i feel a bit better informed now and of course i will ask my clinic at my baseline scan exactly what i'll be doing.

good luck to everyone!

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