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    Can FISH results differ from final CVS results?
    jackandsimone posted:
    Hello. I am 36 years old and 13 weeks pregnant. After receiving the news that I was at high risk for chromosonal abnormalities, I made the decision to do the CVS testing. Last week, I received devastating news that according to the preliminary FISH results, my daughter has trisomy 13. I have been devastated and have been barely able to get out of bed since. I'm awaiting the final results and I guess I was looking for a ray of hope. Has anyone heard of a case where the final CVS results differ from the FISH results? My genetic counselor said that it was unlikely but it has happened. I'm pretty sure I will continue the pregnancy at this point no matter what, but I'm afraid that I would be selfish to do so if the baby were to suffer at all.
    QueenOfStarWars responded:
    Sorry to hear that you are dealing with this

    It would be wonderful if the results were incorrect. I'm no doctor, but I've heard they are pretty accurate (from what I've read). Of course, with any test, you want those final results to confirm.

    Sending some supportive vibes your way.
    Jeannie [Me (37); DH (41); DD 19mos (born at 33 wks on 11/9/2008); EDD 10/18/2010 Pink Team
    43Hope responded:
    I would definitely wait for final results even if a small ray of hope. But also be assured that you would not be selfish to carry the pg/continue. Remember that God gives life and though we do not know how long any of us will live or why things happen as they do--your knowing and loving this little baby will never be selfish.

    I know this may be really hard, but stay strong. I am going to look for a video that I saw on youtube about a family in a similar situation--it may be a serious trigger for tears, but it shows so much love. If I find it, I will post it.

    Me (43), DH (43), (mc) DD (9), (3 mc, ectopic), DS(22 mos) (mc); BFP 5/31: EDD 2/8/2011 Yellow Team
    43Hope responded:
    I found the video, it is called Choosing Thomas, and again, you may not want to watch it yet.

    but here is another website that might provide other information you might be interested in:

    again, ((((HUGS)))))
    Me (43), DH (43), (mc) DD (9), (3 mc, ectopic), DS(22 mos) (mc); BFP 5/31: EDD 2/8/2011 Yellow Team
    Janna1016 responded:
    I'm so sorry you're going through this. Thoughts and prayers are definitely with you.

    I haven't heard of a case where FISH and final results differed, but I have heard of someone whose CVS and amnio results were different. She got a diagnosis of mosaic tetraploidy from CVS (92 chromosomes instead of 46, but not in all cells). Her doctor recommended that she follow up with amnio because mosaic tetraploidy is extremely rare, and they thought it might be confined to the placenta only. In her case, amnio results showed a baby with typical chromosomes-no mosaic tetraploidy.

    Note that this is something I read on an amnio bulletin board, not someone I know IRL.

    I wish you peace in the days to come and hope you get better news soon.

    Janna(40), DH(40), DS(12), DD(10), DD(4), Due 11/2/2010, Yellow Team
    no1phillygirl responded:
    I'm sorry that you are going through this. Unfortunately, I had gone through the same thing with my last loss(3rd). I had the NT scan done and there was alot of fluid on baby's neck. I had the CVS done and 2 days later FISH came back that baby had Down Syndrome. We decided to terminate the pregnancy since we were told that the baby wouldn't make it (very little fluid in sac). We didn't want to prolong it so didn't wait for the final results. We were told that the final results usually confirm FISH especially when there was already a trisomy found. In the end, we found out that there wasn't enough particles for a final confirmation.
    I'm sorry and I wish you all the best.

    Marla(41) DH(31) 10/08 BFP m/c 11/08; saw RE(stage 2 endo and I'M OLD) ivf1 9/09 BFP m/c 11/09; ivf2 2/10 BFP trisomy 4/10 d
    Lainey_WebMD_Staff responded:
    Hi jackandsimone, I will keep you and your family in my thoughts.
    ilovemods replied to Janna1016's response:
    I have just been given the same mosaic tetraploidy result from CVS and now have to wait another 2.5 weeks to have an amnio. I was glad to read, though, that your friend ended up with a baby with typical chromosomes. It's reassuring.
    Derick_James replied to ilovemods's response:
    June 23, 2012
    I am posting this for future moms who are going to google fish test accuracy vs cvs, error rate, chromosomal test accurace etc. My wife underwent the fish and cvs test due to higher risk age at 36 y/o during pregnancy. We were devastated too when we heard our fish test being positive for XYY or super male chromosomal abnormality. According to the doctor if parents would have had a choice to choose between different abnormal chromosomal abnormalities this is the one to choose due to, it has the most minor disabilities. Still, we were devastated by the results.
    We attended different genetic counseling and prepared ourselves for the worse. I stayed sleepless nights trying to research on accuracy of the fish vs cvs test. It states that the fish has a 95% to 99% accuracy and cvs has 99.5% accuracy. This made us more depressed, but made us turn more to God and weep more in prayers.
    After 10 days, I received a call from my geneticist stating that congratulations CVS test came out and it is negative. I couldn't believe what I heard and even our genetics Dr. who is head of mount Sinai stated that throughout her career she's never seen conflicting results from both tests, but it can happen. She explains that the chromosomal abnormality can be localized to the placenta.
    This doesn't end here my wife was also diagnosed with velamentous cord insertion and had a high AFP which is indicative of spina bifida. After several ultrasound everything is normal and my wife is scheduled to deliver June 25 which is her full term.
    I am writing this because i saw multiple postings from different sites that parents who received positive fish tests for xyy, trisomy 21 etc.... opted to terminate their pregnancy without waiting for the CVS. I hope my testimony will give some light and hope to some parents who were in the same boat like us before. Please do not lose hope for behold the power of prayer and faith which cane move mountains. If you have any questions just reply to this post
    An_249657 replied to Derick_James's response:
    I wanted to post this because I also received a false positive FISH test result from Mount Sinai in late summer of 2012 and then went on to get a normal final CVS result. I also went on to do an amnio (at a different hospital, of course) and that result was also normal. The odds of this happening are extremely slim, and in fact, the post above by Derick_James is the only other story I have found of this happening to someone. I was further intrigued by the fact that he and his wife also got their FISH results from Mount Sinai. If Derick_James sees my post, I would so appreciate a reply back to let me know if your wife went on to deliver a chromosomally normal baby? My due date is 2/10/13, and I have been worried my entire pregnancy due to these conflicting (and very unheard of) results, which none of the genetic counselors I went to see could explain.
    Letzzhop replied to Derick_James's response:
    Derick_James — Thank you for sharing your experience. I would like to know how is your baby today. I am going through the same thing but hoping that the CVS test comes back negative from the Fish test, which was positive. I am only 3 months pregnant but I am so devastated that words can't explain. Thank you again.
    Letzzhop replied to An_249657's response:
    Thank you too for sharing your experience. I would like to know how is your baby. I am going through the same thing but hoping that the CVS test comes back negative from the Fish test, which was positive. I am only 3 months pregnant but I am so devastated that words can't explain. Thank you again.
    mmanna123 replied to An_249657's response:
    Hi I am going thru the same, just wanted to know, if everything turned out well.
    thank you so much for sharing your story.
    mair30rn responded:
    How was the outcome?
    jfrito responded:
    I know that your original post is 6 years old but I was wondering if you could provide an update. My wife (43 y/o) and I just received our 10 week CVS FISH results that indicated "male with mosaicism for Trisomy 18". We are extremely concerned but after speaking with our DR he indicated that the results could be a mistake in lab, issue isolated in the placenta or could also be with the baby. We are now scheduled for a anmino test in 5 weeks. Hopeful that we have a healthy baby boy and praying.

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