Is a screening for Down's syndrome ...

[KeepOnPloddingOn]

Generally correct? I know occasionally there can be blips and false positives ... But generally is a high result a positive? I have a 1:27 chance of dc having downs. I have read conflicting info, but some say that getting such a high result generally suggests ds is inevitable - as the screenings are not 100% and a very high result should be taken as a highly likely.

I know this may sound confusing sorry, I am no expert on all this- I have been researching lots and as there are no answers as to why some Get such high results if baby doesn't have downs. So I am starting to believe it means in most cases a very high result such as mine is a 'more than likely' ...

For me it was my bloods giving me this high positive. The nt was 2.10- normal. I am mid twenties.

A result of 1:150 or less is considered high risk by the way. I think if I had a 1:100 it would be different - but our screening was relatively very high ...
Aibu to believe that thiS 1:27 Is not a diagnostic, but a pretty cert dc will have downs....? Any feedback would be appreciated.

I don't really know anyone in person either. But then all my "mum friends" who had their babies at the same time as me are a similar age and I was 28 & 31 when I had the first two.

I was given a 1:14 chance a year ago and DS doesn't have Down's. I had the CVS as I wanted a definite answer and didn't just want to be given more ratios from the Harmony test.

To be honest I don't think the nuchal tests are at all accurate and they don't really mean much. Like others have said someone could have a 1:1500 chance and still have a baby with Down's Syndrome.

I was a total wreck while I was waiting for the results as the hospital made it sound like the baby had Down's and even offered to book me in for a termination over the phone when they called with my test results. I switched from that hospital soon after the whole horrible experience.

Haven't - that is a really good link. I think I had the combined test and your link suggests a 1 in 40 'high risk' result, which is far less than 5%. It also uses the term 'screen positive' which makes more sense than 'positive' as it isn't diagnostic.

ummm... I am still non the wiser but I do really appreciate your trying to explain things. I am not good with numbers I would add though I am educated to Master Degree level, so it is not like I am a completel dope- and yet I certainly struggle to get my head round it all. I genuinely think they could make this national screening test less complex. Layman terms are needed.

The key fact is, as you say, I have that 1:27 chance and that's that.

smitten I think it's barbaric they even discuss such things- as a termination-- at screening level.

Yes, it was awful.

You have to think that you have 26 chances that everything is fine. I worked mine out in percentages and it was something like 96% chance that he didn't have it. It made it easier to deal with.

A CVS will let you know for sure though.

I'm sure all will be ok. Feeling fine today.

Glad you're feeling ok OP, . Hope you're able to get some rest today and have a big Sunday roast!

I've recently been caught up in this statistical nightmare and I read (sorry if someone has already said this) that if you are high risk based on bloods alone then there is a very good chance everything is fine. Sounds like there weren't any soft markers on your scan so that's really good. The Harmony test has a 99% detection rate for downs, but it is expensive at £500. The other option is to have an extra scan at 16 weeks to check for markers? But obviously if you really want to know for sure, as people have said, it's an invasive test x

I heard this too grace both on mn and more significantly from the private sonographer I saw who had just completed her masters in screening for downs. Hope that puts your mind at rest slightly OP!

Wow! Really? I did think this, but didn't dare to believe it is the case! Thanks so much for sharing that ladies xxx

It's all confusing, all I know is after 1 friend of mine was give. a 1:80000 risk of DS and has a child with downs (who is amazing by the way) and another friend who has a 1:10 risk and a child without DS, I decided that I would be having no screening in my pregnancies, I wouldn't personally want an amnio if I could avoid it, nor would I have terminated regardless so I didn't see any point.

Nobody - That's a common view, but as has been mentioned on this thread (and there was a whole previous one on the topic) there are actually a lot of reasons people go for testing other than to help them decide whether to terminate.

Yes, I also got told by the antenatal testing MW that some people think that the formulas weight bloods too heavily when they are not accompanied by increased nuchal - i.e. that where you just have iffy bloods you come out looking higher risk than you should.

Penguin- yep I what to know so I can prepare - not so I can terminate.

Nobody- I do see why you wouldn't again though. Don't even think I would after all this!

My bloods have always been iffy and my family have said it is of no surprise it is my bloods that have put me at risk. Nuchal is fine and I am 26.

Yes, nobodyliveshere. Someone will always be the one even at 1/1000000. The OPs statistics are in heir favour.

Nobody- The other thing to bear in mind is that your friend who got 1/10 and then had an unaffected baby had statistically by far the most likely outcome for her odds. There was a 90% chance that that would happen. Being the 1 from 1/80,000 is, of course, unusual. But the other result only feels unusual in comparison and at an emotional level. Statistically, it is utterly expected.

Do you think a Down syndrome baby would suffer in the womb? Due to heart defects etc? I am aware they do not feel pain until around 20-24 weeks (though the jury is out) I would hate for my baby to suffer inside me and there is nothing I can do.

That is something nobody knows. Please don't torture yourself with it.

If you want my opinion as a biologist (this is not my specialist field) then no, I don't think a fetus can experience pain like a newborn. Firstly the brain is still immature. Secondly, the pain response has evolved for a reason - to protect us from harm - and there is no evolutionary benefit to a fetus feeling pain. Can't alter its behaviour to avoid it, can't cry and let anyone know there's a problem. Therefore no reason for a pain response to have evolved in utero (no selective pressure).

Wishing you well.

Thanks barbarian and mad

Madrigals- I am sure your baby wouldn't have felt a thing in the event of a miscarriage, as they are sadly passing away themselves and I am assuming you miscarried before 24 weeks? Medical science proves any feeling before then is impossible (from what I have read) as neuro paths are not developed enough.

Sorry to remind you of a painful time by asking this. I am just torturing myself. But if I knew my baby had downs and would suffer in the womb I wouldn't be able to bear it! I imagine it is highly unlikely though, and many don't even have heart/ bowel issues.

Thanks mad- you have been particularly lovely though all this. Thank you.

kim - "Really - is the antibody used to detect HIV 100% specific? No - it isn't. So you get false positives."

If you actually read what I wrote, you will see that I said that many blood tests (HIV, for example) give a positive or a negative result. NOT that the HIV test is 100% infallible and never gives a false positive.

And I said that because you made this bizarre claim:

kim147 Sat 28-Jun-14 23:06:07
... you don't get a positive result in medicine anyway if you do blood tests. You get a level of a chemical.

Whatever. Just know that some blood tests do give 'positive' or 'negative' as a result, but triple blood test done during pregnancy is not one of them.