Pre-implantation Genetic Screening

I wanted to share the process of Pre-implantation Genetic Screening (PGS) that we've arrived at in our IVF journey. This procedure is not covered by insurance, so it's understandable that not everyone chooses to have this testing performed when you may be paying so much already out-of-pocket. Since our RE (Reproductive Endocrinologist) told us that basic IVF gives you about a 45-50% chance of conceiving, while doing IVF with PGS (what I call the full monty IVF, because it is a much longer process) increases your chances to 65-70% chance of conceiving. Also, the other benefit is that with typical IVF your chance of miscarriage is about the same as natural conception, so 2-3% chance, while IVF with PGS reduces that to about 1-2% chance. I feel very fortunate that my husband and I live in the state of Massachusetts because insurance is required to cover Assisted Reproductive Technology (ART). We also have a lot of support from our families, so we can afford to include this process in our treatment plan.

I'll share with you what I understand of what the process consists of, and what I've learned from my own research on the method. Remember I'm not trained in this medical background, so don't take it as completely correct, it's my own understanding. I am a Doctor of Physical Therapy, so I have had some education in embryology, but not even close to what your doctor, nurse, and fertility team know!

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Pre-implantation Genetic Screening (PGS)

Once you've completed your egg retreival and they add the sperm to them, they wait for them to fertilize. Once they are fertilized (first 24 hours after the retreival), they wait for about 5 days for them to grow to a certain stage; the blastocyst stage. Refer to this post about the development of the embryo days 1-5 here.

This illustration shows you generally what the blastocyst stage looks like. The zygote by day 5 has about 100 cells and still has its protective Zona Pellucida and that some of the blastomeres have now started to migrate to one area. Now this mass of cells is known as the Embryoblast (or inner cell mass) and will be your future bundle of joy (baby cells!). The zygote cells have also differenciated into what is called the Trophectoderm, which is what will become the Placenta (the sac that contains your bundle of joy). Fascinating right? Ok next step.

Now this is where science is f*cking amazing! Somehow these amazing scientist can expose the Trophectoderm so that they can safely retrieve a few cells, maybe 3-4 total. They are able to retrieve these select number of cells, WITHOUT disturbing your precious baby cells (Embryoblasts). Also, don't ask me how the laser works, you'll have to find someone who works in the lab to answer that question! Love it!

Now, obviously under a microscope this whole process is performed, so with this technology they are able to carefully insert a crazy tiny pipette into the cells of the Trophectoderm to suck them out for testing. What's crazy for me to think about is, that they take these cells and somehow package them up, and are able to transport them to another lab for the genetic testing.

I can't even begin to understand how they do the genetic testing, this is an area that I am not familiar with at all. They are somehow able to count the chromosomes to determine if it has the complete 46 needed for normal embryo development. This testing only looks for chromosomal abnormalities, not specific genetic disorders.

With this testing, THEY WILL KNOW the sex of your baby!! However, they will most likely not tell you the sex of the embryo that they choose to transfer. Sometimes they will choose the sex if you already have children, or more importantly if you have a known genetic disorder that is XX (female) or XY (male) chromosome dominant. I'm guessing that they would be genetic disorders that are life threatening to your potential life-spring.

Time

The genetic lab that is doing the testing of our zygotes told me it takes about 5-7 days for them to get the results back to my doctor. However, the clinic won't tell me about the results until my follow-up with my RE, which is 3 weeks from the retrieval of the cells. My babies do not leave the clinic that I go to, and they are currently frozen (Embryo

Cryopreservation). The fact that you can freeze these little guys and then thaw them is incredible, and makes me feel like we truly live in the future.

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So, now we wait. Next process is wait for my next cycle day 1, and 3 weeks till my follow-up to go over my results, and the Frozen Embryo Transfer (FET) plan of care.

Hope this helps you either prepare, or decide on how you what to proceed with your own IVF process!

Best,

Natasha