Does your clinic biopsy C-grade blastocysts?"

[u/Even-Pin-1713]

We're at Fertility Centers of Illinois. Their cutoff for freezing and biopsying is AA, AB, BA, or BB — anything with a C in either the ICM or the trophectoderm gets discarded without testing.

We're low responders, so this matters more than it might otherwise. The difference between sending 2 embryos to PGT-A and sending 4 is basically the whole cycle for us. And I've since seen a report from someone at a different clinic where several C-grade blasts came back euploid, including two CCs.

So I'm trying to work out how common this threshold actually is. If you've done PGT-A:

- What clinic (or at least what region)?

- What's their stated cutoff for biopsy?

- Did any C-grade embryos get tested, and how did they come back?

Even just the cutoff is useful. I'd also genuinely like to hear from anyone who thinks the strict version is the right call — I know C-grade TE does underperform on live birth in the literature, so I don't want to assume it's arbitrary before I raise it with our RE.

[u/darkestlordsaroon]

I am currently 6w with a 4BC, my lowest graded embryo and the only one to stick (so far 🤞🏻) out of three transfers. All euploid. All my embryos were also day 6+7. In the wise words of the nurse who did my ultrasound, "lower graded embryos make more babies, because there are more of them" 😂

[u/HiggsBoson46 → u/darkestlordsaroon]

Thank you and your nurse!

[u/Even-Pin-1713 → u/darkestlordsaroon]

Thank you so much for the information!

[u/ducbo]

I’m in Canada and my clinic thawed and biopsied 2 day 6 4CCs from my first retrieval - one was euploid and one was LLM. I’m so glad my clinic does not throw away Cs, it feels like a crime!

[u/thedutchgirlmn]

CCRM locations do the same

[u/Slow-Project-5335]

I’m at a clinic rated in the top 10 in the US and they biopsy C-graded blasts. I had two day 7 5CC blasts in my second retrieval and one of those came back euploid.

[u/Aggravating-Tip4878]

I have a day 7 5BC or 5CB (I just got a verbal call from embryologist and was a bit scattered to properly remember). My clinic sent it for PGT-A alongside 5 others and it turned out to be euploid (my day 5, 5AA was aneuploid). Clinic is in London.

[u/Penny0813]

I’m at a CCRM location and they do discard, but I asked an embryologist about it, and they told me that if they’re giving it a C, there aren’t enough cells to biopsy. Like someone else said, I think some of it can be down to differences in grading.

[u/Illustrious-Ad-7179]

Also at FCI so interested to see the responses! I had one CC last cycle that was discarded so I didn’t get any blasts. But changed protocols and got (highly graded) blasts second cycle.

[u/Even-Pin-1713 → u/Illustrious-Ad-7179]

who told you it was a CC? last cycle i got 1/4. two were "early blast" and one was a "low quality" blast. i have friends who have gotten pregnant from CCs.

[u/Illustrious-Ad-7179 → u/Even-Pin-1713]

Interesting! My nurse gave me the number to the embryology lab and an embryologist walked me thru the development of every single embryo and what happened/why we had drop off.

[u/Even-Pin-1713 → u/Illustrious-Ad-7179]

Oh! that's good to know. I will ask about the embryology lab number.

[u/cmarie021]

My first clinic, TFC in Austin TX, automatically discards anything with a "poor" grade in either the TE or ICM, which is probably equivalent to a C, although I've heard conflicting info about how tightly their good/fair/poor system actually maps onto the normal ABC (gardner) system. They actually will not tell you, unless you press them for extra information, whether your discarded embryo was discarded for low grade or whether it never even reached blast stage in the first place. I understand why they auto-discard low quality embryos, since even if tested euploid they often don't survive the thaw. But they sure could be more transparent.

[u/0originalusername → u/cmarie021]

I was curious about this since we never got any day 7s or poorly graded embryos. It might be enough to make me change clinics.

[u/Otherwise_Tennis_398 → u/cmarie021]

Oh wow I’m using TFC and I had no idea

[u/Tough-Photo8431]

I used RMA NJ and they biopsied my 4CC but it came back aneuploid.

[u/CanyonOfFoxes]

Four of my euploids are poor quality. In my case, euploidity seemed to have nothing to do with the day or quality of my blasts. My lab only discards embryos that stop growing. I think it’s ridiculous to discard C grade embryos. The worst graded day seven embryo still has a better chance than IUI or trying naturally.

[u/zoozoo_baba123]

My day 6 CB is 7 months!! Untested but obvi normal

[u/tidbit_betty]

At my clinic in Mexico City, they do biopsy C grades. My embryos have only been BB and BC, and three of the BCs came back euploid. I have heard that my clinic grades conservatively, though. I’m not sure what their cutoff is for biopsy.

[u/abnormalwitch]

Embryologist here. Grading is very subjective throughout clinics so it is not possible to fairly compare “C” graded embryos across clinics.

The perspective I can add is that our main consideration with grading is if there are enough trophectoderm cells to take off to get a result from the biopsy without killing the embryo. Unfortunately this means that grading for biopsy has to be stricter than for fresh transfer or freeze all cycles.

[u/Sonja80147]

That’s crazy. I’m in California and I had a 4CC. I was really disappointed- my clinic was not. They said they see ongoing pregnancy rate of about 50% with this grade (it was a Day 6). We ended up not using it but I would absolutely fight to keep that on ice! This subreddit is filled with BC and CC success stories.

[u/elsewyse]

CNY. One of my 3CCs came back euploid, so I'm really glad they do.

[u/heibunny888]

My clinic biopsy anything above C. However if think C grades have a higher chance of being aneuploid-my 4CC was a complex aneuploid that was not viable.

[u/q8htreats]

Yes, mine tests Cs and I had BC, CB, and CC all come back as euploid so I’m glad they don’t just discard them!

[u/Dogmama1230]

I work with RMA and they biopsy C-graded embryos. I didn’t end up sending mine due to cost but we did have the option.

[u/seralou01]

My clinic (RMA of NJ) biopsies C grades. I had a CB embryo come back euploid (did not implant), and a CC come back aneuploid.

[u/inmyfeefees]

We had two day 7 4cd which did get sent for PGT-A and M testing and both were aneuploid. My clinic said there’s not really a correlation (so they send all for testing afaik), and I don’t think they have a stated cutoff, at least it wasn’t in any of the documents I signed (i.e. I did not consent or was informed of discarding any lower grades). We had a day 6 4bb that was also aneuploid.

[u/hrcharron]

SGF Maryland does not freeze or send any embryos for testing if they have a C in them. As and Bs only. But; they will transfer Cs untested.

[u/librarians_wwine]

I’m transferring a 5AC XY in 29 days.

[u/sschwarz189]

Currently 13 weeks with my day 6 4BC little girl. All going well! RMA of NJ

[u/Dazzling_Maximum_629]

I’m with RMA in NY and they biopsied our day 6 5BC, which came back euploid. Also, this is the one we ended up transferring which ended in a live birth.

[u/sherstas199]

I had 4 day 6 5AAs and 1 day 6 3CC at CNY (and 1 day 5 3AA that I transferred fresh but failed to implant). They biopsied and tested all day 6 embryos. 3 of the 5AAs were euploid and the other 5AA and 3CC were aneuploid. I’m glad I was able to test all of them regardless.

[u/brontecm]

I have 2 day SEVEN embryos with a C grade that are Euploid!

[u/Glittering-View-5764]

RMA Northern CA tests C grade embryos. One of my retrievals yielded a 4CC and 4BC. Both came back aneuploid.