Decision to make: freeze on day 3 or continue with CSS on day 5


#1

I’m so confused. Egg retrieval from my first IVF was done on Tuesday. They got 17 eggs. I got a call the next day saying that only 4 of those eggs were mature and only 3 of those 4 fertilized. She said they had a few others mature overnight. I got a call today saying 5 more matured overnight, and 4 of those fertilized. I had planned on doing CCS (comprehensive chromosonal testing), because I have heard the success rate is higher. True, you can be left with fewer embryos after the chromosonally abnormal ones are weeded out, but the genetic counselor at CCRM said that there’s an 80% pregnancy success rate when two chromosonally normal embryos are transferred back in.

My issue is that the embryologist said that since I only have 7 embryos, I have to decide if I want to continue with the CCS or freeze on day 3. I’m not sure I understand. Isn’t it true that if an embryo isn’t going to survive to day 5 (which is when they would do the biopsy for CCS), it probably isn’t good anyway? She said that sometimes they will freeze at day 3 because then they can transfer back in a day 3 embryo and get it into its natural environment so that it has a better chance of surviving. But I’m thinking I would still want to do the chromosonal testing since the success rate is higher. Or should I not do it since I don’t have that many embryos to work with, and keeping those embryos out until day 5 might harm them more? Any thoughts on this? What would you do in this situation?

Note: Fresh transfer isn’t an option because my uterline lining hasn’t had any preparation.


#2

In the past day 3, or cleaved, embryos survived the freeze thaw better than day 5- I am not sure that is still the case with vitrification.

I believe they can still freeze them now and when they thaw them they can grow them to day 5 for testing.

I definitely see no risk in growing them out unless it is a freeze/thaw related risk. In my opinion the whole ‘better environment’ arguement is unfounded.


#3

Thanks for your reply. All of them were ICSI, since I’m using donor sperm. So would the four that matured overnight be called rescue ICSI? And are chances really much lower with rescue ICSI as opposed to regular ICSI?


#4

Just because you are using donor sperm doesn’t mean they were done with ICSI - actually, that is probably a case for not using ICSI. ICSI is when the sperm is actually manually inserted into the egg to fertilize. Regular IVF is where many sperm are put in a petri dish with the egg and hopefully fertilize naturally. Rescue ICSI is done when the embryologist realizes that the eggs are not going to get fertilized with traditional IVF.

SOmetimes eggs fertilize later because they were not fully mature at retrieval, and they cannot fertilize until they are mature.

Did your RE tell you that they used rescue ICSI?

Also, I know of no reason why ICSI’d (rescue or not) would effect the quality. Many, many people using IVF have do use ICSI (like me) because of severe male factor infertility. My DD was conceived with ICSI.


#5

The nurse at CCRM told me that when they’re working with donor sperm, they won’t do regular fertilization - they will only do ICSI. I wonder if that’s not the case… At any rate, I know they did ICSI for mine. I only had 4 mature eggs right after retrieval, so they did ICSI on those 4 and only 3 fertilized. And then 5 more eggs matured overnight, so then they did ICSI on those the next day. Four of those fertilized. So I’m thinking the ones that matured overnight are the ones that had rescue ICSI performed…? Or is not considered rescue ICSI if the ICSI was performed as soon as the eggs matured? Everything I’ve read says that rescue ICSI doesn’t have a high success rate. I should stop researching before I drive myself crazy… :slight_smile:


#6

It would have been regular ICSI if the eggs just took longer to mature. Rescue ICSI is, like I said before, when the eggs fail to fertilize with IVF and they try to save them with ICSI.

We all worry and obsess! Perfectly natural!


#7

Thanks. :slight_smile: And maybe there’s hope yet… :cross:


#8

[quote=regGe]I’m so confused. Egg retrieval from my first IVF was done on Tuesday. They got 17 eggs. I got a call the next day saying that only 4 of those eggs were mature and only 3 of those 4 fertilized. She said they had a few others mature overnight. I got a call today saying 5 more matured overnight, and 4 of those fertilized. I had planned on doing CCS (comprehensive chromosonal testing), because I have heard the success rate is higher. True, you can be left with fewer embryos after the chromosonally abnormal ones are weeded out, but the genetic counselor at CCRM said that there’s an 80% pregnancy success rate when two chromosonally normal embryos are transferred back in.

My issue is that the embryologist said that since I only have 7 embryos, I have to decide if I want to continue with the CCS or freeze on day 3. I’m not sure I understand. Isn’t it true that if an embryo isn’t going to survive to day 5 (which is when they would do the biopsy for CCS), it probably isn’t good anyway? [/quote]

Yes.

She said that sometimes they will freeze at day 3 because then they can transfer back in a day 3 embryo and get it into its natural environment so that it has a better chance of surviving.

The natural environment of a day 3 embryo is the fallopian tube, not the uterus. The natural timing has a blastocyst arriving in the uterus from the tube on day 5.

But I’m thinking I would still want to do the chromosonal testing since the success rate is higher.

That’s a success rate per transfer, not per retrieval.

If you only get 1 or 2 blasts, and you are willing to transfer that many, then the test cannot increase your chance of success at all. It might eliminate an unnecessary transfer of genetically defective embryos, but it can’t make them better embryos.

That’s the difference between success rates per transfer and cumulative success rates per retrieval. We can increase success rates per transfer by eliminating bad embryos, but it does not increase the chance of one retrieval yielding a pregnancy. It only helps some of those who would get pregnant anyway achieve their pregnancy sooner, and that is only true if they have many embryos to choose from. If they have just one embryo, the uterus/embryo can do its own test, as it has done for thousands of generations.