Day of biopsy

[sprite]

One more question! So, I have read that some clinics are now doing a biopsy on day 5 because they say embryos can self-correct and day 5 when you get more cells will be more accurate.

Do you think all clinics will eventually go to a day 5 biopsy?

What are the good and bad points of opting for a day 5 biopsy?

Thanks again!

[Janed]

Guys, Dr. Potter asked me to post this for him

We are participating in an NIH funded clinical trial to answer that question. Currently, my preferred approach is to do day 3 biopsies and the do day 5 biopsies only on those where the day 3 results come back inconclusive or with a specific abnormality that has a high likelihood of being a mitotic error (cell division error after fertilization) and therefore being a candidate for 'self correction'. The does not appear to be any measurable advantage at this point of doing a day 5 biopsy when using GSN. Clinics that are using other less reliable methods of pgd need to use day 5 biopsies because they cannot get accurate results with a single cell. Because of the increased cost of having to do two procedures. This is particularly the case when patients are from out of town.

[nuthinbutpink]

So, with a day 5 biopsy, is a day 6 transfer possible with the timing involved with GSN or would you have to do a FET?

[Hopingandpraying]

How exactly do you know what is a mitotic error, or what isn't? Is that only possible with GSN? Almost all of my abnormals were polyploid. For instance, I had 2 XXXXs with 4 copies of every other chromosome tested. I also had an XXYYY with 6 copies of every other chromosome. Were these most likely mitotic errors that occurred after fertilization, or was the XXYYY embryo really fertilized by a sperm that contained 3 Ys and an X?

[Dr. Potter]

One more question! So, I have read that some clinics are now doing a biopsy on day 5 because they say embryos can self-correct and day 5 when you get more cells will be more accurate.

Do you think all clinics will eventually go to a day 5 biopsy?

What are the good and bad points of opting for a day 5 biopsy?

Thanks again!

We are participating in an NIH funded clinical trial to answer that question. Currently, my preferred approach is to do day 3 biopsies and the do day 5 biopsies only on those where the day 3 results come back inconclusive or with a specific abnormality that has a high likelihood of being a mitotic error (cell division error after fertilization) and therefore being a candidate for 'self correction'. The does not appear to be any measurable advantage at this point of doing a day 5 biopsy when using GSN. Clinics that are using other less reliable methods of pgd need to use day 5 biopsies because they cannot get accurate results with a single cell. Because of the increased cost of having to do two procedures. This is particularly the case when patients are from out of town.

[Dr. Potter]

How exactly do you know what is a mitotic error, or what isn't? Is that only possible with GSN? Almost all of my abnormals were polyploid. For instance, I had 2 XXXXs with 4 copies of every other chromosome tested. I also had an XXYYY with 6 copies of every other chromosome. Were these most likely mitotic errors that occurred after fertilization, or was the XXYYY embryo really fertilized by a sperm that contained 3 Ys and an X?

It is really only known if you use GSN. With GSN we know the haplotypes of both parents and so can tell from whom the errors are coming from. There are certain patterns that suggest mitotic error versus meiotic error. When there are multiple errors, mosaicism is not important because you are always dealing with all abnormal cells whether mosaic or not.