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By Imogen Rossam

Pre-implantation Genetic Screening is an exciting technology that is greatly increasing the success rates of IVF.  What is it exactly and it is right or you?

I never knew what an “emotional rollercoaster” meant until I started my own IVF journey.  The hardest part of this rollercoaster, as I am sure those of you who are on this journey with me will agree, is that there really is no telling when the ride is going to stop, or when the next downhill or uphill will begin.  There is no burly, overall-clad, ride-operator whom you can stop to ask, “excuse me sir, but how long will this ride take exactly?”.  There are no guarantees in this journey of infertility we are on.

Having suffered multiple unsuccessful IVF’s myself, I have quite often felt like I would like to pull the emergency stop button and get off the ride immediately.  When those feelings of ‘enough is enough’ become overwhelming and you just don’t want to play anymore.

During our third round of IVF, our Doctor suggested that we try Pre-implantation Genetic Screening of our embryos before moving forward with embryo transfer.  Initially my husband and I choked at the thought of having to incur more time and costs but after understanding exactly what it is, and how it can impact on the success of an IVF cycle, it made perfect sense.

Let’s look at what Pre-implantation Genetic Screening is, and decide for yourself whether it’s an avenue you would possibly like to explore on your own journey too.

What is Pre-implantation Genetic Screen?

Pre-implantation genetic screening or PGS is the genetic evaluation of an embryo.  The Cape Fertility Clinic explains it as the ability to detect chromosome abnormalities or chromosomal rearrangements prior to embryo transfer.

In simpler terms, it is a highly specialised procedure done by an embryologist which analyses the genetic material of a Day 5 or Day 6 old embryo.  The embryologist microscopically takes some DNA material from the embryo and tests it for genetic abnormalities or hopefully ‘normalities’.  Every egg and every sperm carry 23 chromosomes, which together should create an embryo with 46 chromosomes.  The PGS test is looking for the occurrence of these 46 chromosomes.  If there are less or more chromosomes it could result in miscarriage or birth defects of a foetus.

Click here to watch a easy to understand video on what PGS is in a nutshell.

Why is PGS useful?

PGS allows the doctors and embryologists the opportunity to choose the better embryos for embryo transfer. It also makes sure that the embryos they are transferring are chromosomally normal and do not carry abnormalities like too many (as with down syndrome) or too few chromosomes.  The specialists suggest that PGS be strongly considered by older women (over 35) or couples who have had repeated failed IVF cycles previously.

Why should I consider PGS?

A staggering 70% of miscarriages in early pregnancy are as a result of chromosomal abnormalities.  Without PGS you will not know beforehand if abnormalities exist or not.   According to genetic specialists, Genesis Genetics, “IVF cycles that do not include PGS, embryos are chosen primarily on their visual quality – which cannot distinguish chromosomally normal embryos from abnormal ones. IVF cycles that do include PGS enable the identification of embryos with normal chromosomes, and are more likely to result in a pregnancy that leads to a healthy baby.”

Is there a risk that an embryo can be damaged during PGS?

Thanks to the advances in medicine we see today, and how its improving each year, the risk of damage to the embryo is very low if you are using a high-quality laboratory for your testing.

How they biopsy the embryo is through a process called trophectoderm biopsy.  The take a small number of cells from the trophectoderm (cells that will become the placenta eventually) and do not touch cells from the inner cell mass (cells which will become the foetus eventually) which means technically the cells that make up the foetus do not get disturbed at all.

In closing

In my humble opinion, I would strongly advise any friend or women going through IVF to consider PGS to improve your chances of a pregnancy.  It makes the huge, gaping hole of worry and ‘what ifs’ that much smaller.  You are never guaranteed to have a baby; no Doctor will ever give you a 100% pregnancy rate because there is never that kind of guarantee.  But thanks to technologies like PGS, our success rates can be improved… That rollercoaster can be slowed down just a little bit, and maybe enough for us to look out at the scenery and enjoy it for a moment.