Thoughts on GSN for Mature Mamas

[Tiny Dancer]

Just wondering your thoughts on using GSN when you are AMA. I've heard from some others that they believe GSN may eliminate so many eggs that it lowers your chance of having any embys to transfer. On the flip side if the embys aren't "passed" by GSN are they likely to implant and result in a healthy baby?

[Daisynyc]

What is GSN?

[Carole]

Hi Tiny Dance and Daisynyc,
I am not sure what GSN stands for either but in the context of AMA (advanced maternal age) , I am guessing you might be asking about aneuploidy screening. As we age, our eggs are more likely to finish the final growth and maturation stages with errors in chromosome replication and division, which sometimes results in eggs with either more or fewer of a particular chromosome. For instance, in Trisomy 21, the egg that is fertilized had a double set of chromosome 21, after getting a Chromosome 21 from the sperm, the embryo now has 3 total chromosomes 21 which causes all the effects you see with Down's syndrome. My opinion on this is mixed. In theory, it makes a lot of sense to test for aneuploidy and not transfer embryos with abnormal chromosome numbers, especially since many trisomys lead to miscarriage and loss. in my clinic, the doctors were initially enthusiastic but phased it out over time because patients were not happy with the results if as you say, all the embryos were aneuploid and they couldn't have a transfer. The doctors then had some doubts as to whether the aneuploidy tests were always accurate. On one occassion, they had an older patient do a split cycle with an egg donor and had both her and the donors embryos tested and aneuploidy was detected in both women--even the donor was a proven donor with several previous donor pregnancies from her eggs. I don't know what that result means. Did the lab get it wrong? Even after following up with the lab-they stood behind their results- it wasn't obvious how to counsel patients. Could younger patient have some aneuploid cells in the embryo that didn't arise from the egg but from later steps when the daughter cells replicated? Could younger embryos somehow rid themselves of these aneuploid cells, leading to normal pregnancies. We don't know, but it was hard to really advocate for aneuploidy testing for every patient of AMA after that case. In theory, it should work and some labs have reported really excellent results, but others have not reported a big improvement in pregnancy rate. Hope this answers your question- here are also three links to posts that have additional info on aneuploidy testing. Carole
http://fertilitylabinsider.com/2011/...is-aneuploidy/http://fertilitylabinsider.com/2011/...is-aneuploidy/
http://fertilitylabinsider.com/2010/...ss-than-hoped/http://fertilitylabinsider.com/2010/...ss-than-hoped/
http://fertilitylabinsider.com/2010/...nical-promise/http://http://fertilitylabinsider.co...nical-promise/

[Tiny Dancer]

Thanks Carole for your quick response and for the information. Much appreciated.

I should have been more specific about GSN. It's a company, Gene Security Network, and they do a 24 chromosome probe.