In this session, Ana Sousa Ramos, Laboratory Manager, Clinical Embryologist (ESHRE) at AVA Clinic, Lisbon, Portugal, who has discussed the differences in embryo grading systems.
Recent studies show that it is better to select the trophectoderm. If you have 2 blastocysts and 1 is with a good ICM, and the other doesn’t have a good ICM but has a very good trophectoderm, you choose the one with a very good trophectoderm.
It is up to the embryologist to choose the embryo in this situation, depending on how it is done in this specific lab. It is very important because the ICM will develop the embryo afterwards, but you have to have something that is equilibrated between the ICM and the trophectoderm.
Sometimes it’s difficult to decide, you have to see the blastocysts to decide, but the latest studies show the best implantation rate is related to the best trophectoderm.
If you’re less than 38-years-old, even with your diagnosis, I would go for a single embryo transfer since you have blastocysts instead of transferring 2. So, I’m not sure about your age, but it is important to know that.
As I’ve mentioned, freezing at the morula stage is not so common. The embryologists usually don’t like this stage. In my experience, sometimes, I do prefer freezing at the morula stage and thawing after for a frozen embryo transfer cycle. I freeze morulas, and then I thaw it 1 day before the transfer, and morulas survive nearly 100%. Thanks to the vitrification method good morulas have a very good survival rate.
You need to have a well-established vitrification procedure, the blastocyst cell cavity interferences with water, the blastocyst has cryoprotectants that interfere with the survival rate. That’s why some centres do like to collapse the blastocyst before freezing. I don’t collapse the blastocysts, and I have good results.
In our centre, I do most of the freezing on the blastocyst stage, but in my experience, the rates with morulas are very good.
Not everybody agrees on that. I think that it depends on the overall treatment. You have to see the couple you are going to treat, you have to know how many attempts they had, how old they are. Most important is if they are prepared for not having a transfer.
For instance, in my clinic, I had older patients, in Portugal, we can do treatments up to 50 years old with egg donation, but sometimes they have their own last try with their own eggs, and the next step will be a donation. You have to talk with the patients, you have to see if they are prepared for this.
For example, in Scandinavian countries, some people prefer a more natural cycle, and sometimes they believe that the conditions of the women are better than the incubators in the lab, and sometimes they want to give it a try, and they prefer not to transfer at the blastocyst stage. Therefore, we should always talk with the patients to recognize their expectations.
At 44, I would recommend doing the genetic testing of the embryos. If you get 2 blastocysts, and if they are of good quality, you can do preimplantation genetic testing to see if they are okay, because, after 40, you have an increase of aneuploid embryos and trisomies. In most clinics, when you have so many failures with your eggs, usually they start to recommend going for the egg donation process.
If you still want to try with your own eggs, I understand that, but you should try doing the preimplantation genetic testing.
I’m not sure if the quality of blastocyst quality will allow you to do the preimplantation genetic testing, but it’s something that you have to consider.