DISCLOSURE:
This is not a scientific explanation. I am not a doctor or any type of medical professional. I am just someone trying to having a family that is affected by this.
From the time we found out about my husband's balanced translocation, I became fully immersed in learning about Pre-implantation Genetic Diagnosis (PGD). Long and short of it is that it is a process where the embryos can be tested and only chromosomally normal embryos can be selected for transfer. Pretty cool, huh? This was a huge relief to me because I wasn't a big fan of spending beaucoups of money on IVF cycles, just to have miscarriages.
Basically the process goes something like this.... after your Egg Retrieval, the eggs are fertilized and grown to Day 3 (or Day 5 - see FAQ's below for more info on that). On Day 3, an embryologist takes a biopsy, removing one cell from each of the embryos and sends the cells off to be tested. On Day 5, you get a report of which embryos are balanced or normal and only those embryos would be selected for transfer.
So even though you might have a beautiful blastocyst on Day 5, the PGD report may show that it is not chromosomally normal and therefore, it wouldn't make sense to transfer it because it either a) wouldn't take; b) would implant and then later miscarry; or c) may result in a still birth or baby with severe abnormalities.
There are various types of PGD testing and the best one is determined based on the particular condition being tested. In our case, the first PGD cycle, we did Fluorescent in-situ Hybridization "FISH" which uses probes to attach to certain segments of DNA. We tested for the balanced translocation and we opted to test 5 additional chromosomes for aneuploidy (the most common chromosomes involved in problems were selected).
The second time we did PGD, we used "Microarray" which allowed us to test all 46 chromosomes. Once we determined we were a candidate, we decided to go this route because we felt like if we were going through this process anyway, we wanted as much information as possible. I would hate to transfer embryos that didn't have the translocation, but later miscarried because of some other issue. So I was thrilled to have this extra data.
Both PGD cycles, we got some really great information....and most importantly, we found out that we DO make some normal embryos! The first cycle, 2 out of the 10 Day-3 embryos were normal and the second time, 5 out of 11 Blastocysts (Day 5/6) were normal.
Here were some of my questions on PGD for balanced translocations, that I hope may help someone else:
1. How much does PGD cost?
The biopsy, which is paid to your IVF Center, is between $1500 and $2000 and the PGD is typically $2500-3500. This is ON TOP OF the normal IVF cycle costs.
2. If they do a biopsy of the embryo and are sending it to some other state for PGD, how does the embryo get shipped back in time for my transfer?
I am kind of a logistics girl, so maybe not everyone is as troubled by this as I was. But, the reality was the embryo doesn't get shipped. Just a CELL (or CELLS) from the embryo gets shipped off for testing. The embryo continues on growing without that cell in your IVF Center.
3. Should I do a Day 3 or Day 5 trophectoderm biopsy?
This is actually relatively new territory for me and I think fairly new to the IVF world. In the past, most people did biopsy on Day 3 and transfer on Day 5. On Day 3, the embryo should have 6 to 8 cells, so if you are taking 1 of those 6 or 8 cells, theoretically, you could be "harming" the embryo a bit. By Day 5, if the embryo is a blastocyst, it has an inner cell mass, which becomes the baby and an outer cell mass, which becomes the placenta. The theory goes that if you wait until Day 5, you can take a biopsy of the trophectoderm, the outer layer, and that is not as "intrusive." Additionally, you can take a cluster of cells (rather than just 1 cell as is done on Day 3) and this reduces the likelihood of mocaism, which basically means that the 1 cell isn't representative of the whole.
When I heard this I was sold on Day 5 biopsy; however, there is a downside....you have to freeze the embryos. If you do the biopsy on Day 5, by the time you have the PGD results, it would be Day 7 and that exceeds the max time they like to keep the embryos in culture and your lining might not be at it's prime either. So, along with freezing, you not only have a month + of wait time, but you may have the added cost of a FET. Also, you have the risk of the embryos surviving the thaw. My understanding is that if your lab uses vitrification to freeze, that they lose very few embryos through that process. My lab still uses the slow freeze and weren't real comfortable with the risk that we lose healthy embryos, so they preferred the Day 3 biopsy. Turns out the PGD test got botched, so I got both a Day 3 and a Day 5 biopsy. Read more here.
4. So does this mean I will know the sex of the embryo?
One of the things that was amazing to me is that PGD is the process used in sex selection. So, when you are doing PGD for other purposes, you may be surprised to find that you can determine the sex of the embryos at this very very early stage. I would strongly consider how much you want to know and ensure you communicate with your PGD center, RE and IVF Center. Both times I found out the sex of the embryos by mistake (the first time it was announced at the transfer by my doctor, when I didn't really want to know. The second time, I found out while innocently reading the PGD report to see how many were healthy and there before my eyes were the XX or XY's). I will tell you that for me knowing the sex of the embryo made the losses SO much harder. The dream of twin boys or even if one made it, one son, was just so real during that 2ww and the loss was just so much more tangible with that added information. It's a personal decision, but I just share our experience because I wasn't aware of how little it was handled.
What other questions do you have? No guarantee I'll have answers, but I'm glad to try. I found very few people who had used PGD, so I think it's important to help each other!!
This is not a scientific explanation. I am not a doctor or any type of medical professional. I am just someone trying to having a family that is affected by this.
From the time we found out about my husband's balanced translocation, I became fully immersed in learning about Pre-implantation Genetic Diagnosis (PGD). Long and short of it is that it is a process where the embryos can be tested and only chromosomally normal embryos can be selected for transfer. Pretty cool, huh? This was a huge relief to me because I wasn't a big fan of spending beaucoups of money on IVF cycles, just to have miscarriages.
Basically the process goes something like this.... after your Egg Retrieval, the eggs are fertilized and grown to Day 3 (or Day 5 - see FAQ's below for more info on that). On Day 3, an embryologist takes a biopsy, removing one cell from each of the embryos and sends the cells off to be tested. On Day 5, you get a report of which embryos are balanced or normal and only those embryos would be selected for transfer.
So even though you might have a beautiful blastocyst on Day 5, the PGD report may show that it is not chromosomally normal and therefore, it wouldn't make sense to transfer it because it either a) wouldn't take; b) would implant and then later miscarry; or c) may result in a still birth or baby with severe abnormalities.
There are various types of PGD testing and the best one is determined based on the particular condition being tested. In our case, the first PGD cycle, we did Fluorescent in-situ Hybridization "FISH" which uses probes to attach to certain segments of DNA. We tested for the balanced translocation and we opted to test 5 additional chromosomes for aneuploidy (the most common chromosomes involved in problems were selected).
The second time we did PGD, we used "Microarray" which allowed us to test all 46 chromosomes. Once we determined we were a candidate, we decided to go this route because we felt like if we were going through this process anyway, we wanted as much information as possible. I would hate to transfer embryos that didn't have the translocation, but later miscarried because of some other issue. So I was thrilled to have this extra data.
Both PGD cycles, we got some really great information....and most importantly, we found out that we DO make some normal embryos! The first cycle, 2 out of the 10 Day-3 embryos were normal and the second time, 5 out of 11 Blastocysts (Day 5/6) were normal.
Here were some of my questions on PGD for balanced translocations, that I hope may help someone else:
1. How much does PGD cost?
The biopsy, which is paid to your IVF Center, is between $1500 and $2000 and the PGD is typically $2500-3500. This is ON TOP OF the normal IVF cycle costs.
2. If they do a biopsy of the embryo and are sending it to some other state for PGD, how does the embryo get shipped back in time for my transfer?
I am kind of a logistics girl, so maybe not everyone is as troubled by this as I was. But, the reality was the embryo doesn't get shipped. Just a CELL (or CELLS) from the embryo gets shipped off for testing. The embryo continues on growing without that cell in your IVF Center.
3. Should I do a Day 3 or Day 5 trophectoderm biopsy?
This is actually relatively new territory for me and I think fairly new to the IVF world. In the past, most people did biopsy on Day 3 and transfer on Day 5. On Day 3, the embryo should have 6 to 8 cells, so if you are taking 1 of those 6 or 8 cells, theoretically, you could be "harming" the embryo a bit. By Day 5, if the embryo is a blastocyst, it has an inner cell mass, which becomes the baby and an outer cell mass, which becomes the placenta. The theory goes that if you wait until Day 5, you can take a biopsy of the trophectoderm, the outer layer, and that is not as "intrusive." Additionally, you can take a cluster of cells (rather than just 1 cell as is done on Day 3) and this reduces the likelihood of mocaism, which basically means that the 1 cell isn't representative of the whole.
When I heard this I was sold on Day 5 biopsy; however, there is a downside....you have to freeze the embryos. If you do the biopsy on Day 5, by the time you have the PGD results, it would be Day 7 and that exceeds the max time they like to keep the embryos in culture and your lining might not be at it's prime either. So, along with freezing, you not only have a month + of wait time, but you may have the added cost of a FET. Also, you have the risk of the embryos surviving the thaw. My understanding is that if your lab uses vitrification to freeze, that they lose very few embryos through that process. My lab still uses the slow freeze and weren't real comfortable with the risk that we lose healthy embryos, so they preferred the Day 3 biopsy. Turns out the PGD test got botched, so I got both a Day 3 and a Day 5 biopsy. Read more here.
4. So does this mean I will know the sex of the embryo?
One of the things that was amazing to me is that PGD is the process used in sex selection. So, when you are doing PGD for other purposes, you may be surprised to find that you can determine the sex of the embryos at this very very early stage. I would strongly consider how much you want to know and ensure you communicate with your PGD center, RE and IVF Center. Both times I found out the sex of the embryos by mistake (the first time it was announced at the transfer by my doctor, when I didn't really want to know. The second time, I found out while innocently reading the PGD report to see how many were healthy and there before my eyes were the XX or XY's). I will tell you that for me knowing the sex of the embryo made the losses SO much harder. The dream of twin boys or even if one made it, one son, was just so real during that 2ww and the loss was just so much more tangible with that added information. It's a personal decision, but I just share our experience because I wasn't aware of how little it was handled.
What other questions do you have? No guarantee I'll have answers, but I'm glad to try. I found very few people who had used PGD, so I think it's important to help each other!!
