Advanced search

Pregnant? See how your baby develops, your body changes, and what you can expect during each week of your pregnancy with the Mumsnet Pregnancy Calendar.

Down's Screening Test - 1 in 110 , cut-off 1 in 200. I'm 35y 10m - Amnio next? NT scan good. Very confused & upset. Please help

(32 Posts)
mumtojennifer Thu 27-Aug-09 16:40:31

I had mu nuchal trans scan at 12wk and result was good, nice and narror.

Had blood test on Monday 24Aug. Doc phoned this afternoon to advise result is 1 in 110 risk of Down's.

I am 35y and 10m old and am currently 15wk2d pregnant. This is my second baby. I think I had test with first and was ok (I was only 32 then)

I am incredibly confused. Most information indicates that on their own the NT scan can identify about 75-82% of Down's babies and the blood test about 60-70% but that together thet predict about 92-95%.......but how can I work the maths from that when my NT is good and blood bad?

I have no idea what to do. I am booked to see my consultant on Tuesday next week anyway but between now and then I may go slightly mad trying to think it through.

Haven't called hubby yet cos want it straight in my head before I do.....

lljkk Thu 27-Aug-09 16:55:06

You haven't cited an accuracy statistic for 'False' positives, that's important, too, in assessing the value of your test results.
Sorry to hear you're going thru this.

mankymummymoo Thu 27-Aug-09 16:59:04

Maybe you need to concentrate whether based on the information you have (ie 1 in 110) you NEED to know whether your baby has Downs or not...

Sorry if this seems to simplified, but I was one in 30 with DS and I just felt that although there was 29 out of 30 chance he didnt have downs, i wanted to know one way or the other as I couldnt face going through the rest of the pregnancy with the worry.

dont forget an amnio has a 1 percent chance of miscarriage.

Try and stay strong, based on the bloods there is still a 109 out of 110 chance your baby is negative for Downs.

philmassive Thu 27-Aug-09 16:59:34

You must be feeling so confused.

My experience was similar - 1 in 125 down's likelihood with ds 1 and 1 in 250 with ds2. I didn't take things any further - no CVS or the thing that I have totally forgotten what it's called and they put a needle in and test the fluid.

The blood tests are extremely inconclusive, and not reliable at all.

The chance of miscarriage with a CVS or needle thingy (it'll come back to me, the name!) is 1 in 100 or less - worse odds than your baby being downs.

Having told my consultant why I was just going to accept the result of the blood test and not act upon it he told me that in my position he would have encouraged his wife to do the same thing.

I knew in my mind that I would not terminate my pregnancies if the babies had been DS, so there was no need to take further tests.

Please don't fret about this blood test result - speak to your consultant, and think about what you would do in the (extremely unlikely) event you discovered your baby was DS. If you would keep the baby then I would put it to the back of your mind and enjoy the pregnancy.

In this situation you will find that they are extra careful about looking for downs markers at your 20 week scan. I found this scan hugely reassuring.

Neither of my ds's have downs, despite the rotten odds that I had.

One midwife told me 'whether you have a result of 1 in 2500 or 1 in 100, everyone has the 1'. The test is useless, they factor in your age when working out the results and so as you get older your results get worse automatically, nothing to do with what they find in the blood.

Please please don't fret. Remember that you are 109 times more likely not to have a baby with DS than you are to have one.

Hope this helps.

Erbert Thu 27-Aug-09 17:07:13

Hi mumtojennifer - I got a 1 in 115 risk last year, slightly different though as risk from bloods alone as I did not have an NT scan. I know how you feel, it's horrible.

The Wolfson give good information on the odds of getting a positive result, and it's worth noting for the Quadruple test that the odds of getting a screen positive reult (ie greater than 1/250) is about 1 in 20 for all women, and 1 in 23 of these women will have an affected pregnancy. Worth reading here:

I spent a long time thinking my odds and concluded that my chances were 50/50 - my baby either had Downs Syndrome or it did not. Because my 'odds' were better that the risk of amnio I did not have one, however I did have two very detailed scans which revealed no markers which reassured me very much.

It might be worth taking a closer look at your actual results, as it turned out for me that the numbers were very similar previously, so I believe that being over 35 for my last pregnancy was the factor which pushed me from 'low' to 'high' risk.

Hope this helps, it's a horrible time.

alittleteapot Thu 27-Aug-09 17:08:40

Where do you live? I recommend that you try and have a second scan somewhere like the Fetal Medicine Centre on Harley Street. THey scan for several more markers which gives you a more realistic result. I can see you're in a difficult place because your odds of there being a problem are the same as the odds of a miscarriage if you have futher invasive tests. If you can honestly say you don't mind not knowing then leave it but if you want more information a more sophisticated scan can give you this. LIke you I had a very good nuchal scan result but one of my hormones came up low in my blood test which reduced my odds to 1 in 86 of downs. We went to the FMC where they added nasal bone, heart, stomach into the equation and my odds fell to 1 in 1600. I don't know what I would have done with the info but i needed to know a bit - like you my odds were high risk but not high enough to go for invasive testing, for us anyway.

Good luck, it's hard at this stage of pregnancy when it all seems a bit abstract anyway.

Erbert Thu 27-Aug-09 17:09:00

Sorry, Wolfson link here

tinkerbellesmuse Thu 27-Aug-09 17:13:21

I'm sorry you are feeling so confused it is must be a very difficult time for you.

My advice would be to talk with your DH and think very carefully about what you would do if your baby does have downs. If you would continue with your pregnancy then put it to the back of your mind and remember that there is a 109 out of 110 cance that your baby will not have downs.

I don't think it is terribly helpful to get too caught up with the maths (it is not accurate) and this may not be helpful for you but both my Nuchal scan and bloods showed very low risk but CVS confirmed my DS had downs. If you feel you need to know then the only way to be sure is to go ahead with the amnio or CVS.

Good luck and best wishes.

pea1 Thu 27-Aug-09 19:06:09

Hello mumtojennifer

my husband and I had a difficult few days when i had my 13week scan...nuchal fold, etc all fine but bad blood result, which combined with my age (41) gave me a 1/35 risk. Felt v depressed for a couple of days, but then managed to get it into perspective ie 34/35 poss of everything being ok. I think it's important to remember that these tests are not diagnostic. Because we had tried v hard to get pregnant, we ended up deciding that we didn't want to have CVS/amnio and are just carrying on regardless. I have also been v heartened by hearing from a number of people who all had far worse odds than me ie 1/10, 1/5, etc whose babies have been fine. If you would keep the baby whatever, then you may not even want the test - or you may simply want to be fully informed. Either way, i know it's hard but try not to get too freaked out. If it's of any help, I am feeling fine about it now i've made a's the indecision that's the tricky bit i think. Hope this helps ...x

emmatrev Thu 27-Aug-09 22:02:44

I was in a similar situation - odds of 1/120 after combined test - I did find it agonising as they are really not bad odds but still within the high risk category so you feel you have to decide something. I wanted to post because unlike most others here I opted for an amnio after a lot of thought. I found the Antenatal Results and Choices helpline extremely helpful - their counseller I spoke to was very empathetic and also had plenty of experience and insight,I would recommend calling them to talk it through. I opted for the amnio in the end for the security of knowing but also mainly because all the research I did indicated that the risk of miscarriage is in fact much much less than 1 in 100 as long as the test is done by someone who does it a lot, ie someone at a fetal medicine unit at a large hospital. That is what the ARC advises. I also have to admit that I paid £450 at the Fetal Medicine Centre for Prof Nicolaides to do it himself, it seemed the best way to reduce anxiety (he does amnio and CVS himself there on Wednesdays). The result was normal and I did not miscarry and that is overwhelmingly likely to be the case for you too. There is a thread here under pregnancy specifically about antenatal results and choices as well, I think it is called that, that has links to some of the research on miscarriage. I don't think there's much chance of avoiding an anxious time for a couple of weeks but it will resolve itself, inevitably, at the birth it not before. The only way to be completely free of worry sooner is to have the amnio. Best of luck

Themasterandmargaritas Thu 27-Aug-09 22:16:44

It's difficult to go through this. I was almost exactly the same age as you, with dc3 and was given a 1 in 10 risk.

We were not in a position to have an amnio due to where we were living and it would have been difficult to travel to a place where it could happen.

It helped to remember that the tests are not terribly reliable and that odds are just that, odds.

You could ask your consultant for a more detailed anomaly scan/regular scans to look for markers for Down's syndrome.

I suggest that you and dh need to think carefully what you would do if an amnio or scan revealed any kind of disability and what you would do, not just if the baby has Down's syndrome.

Fwiw, my baby did not have Down's syndrome.

FabBakerGirlIsBack Thu 27-Aug-09 22:19:42

If you feel you don't want to have a baby with Down's Syndrome then you will have to have an amnio to know for sure.

bubblesincambridge Fri 28-Aug-09 10:42:04

Risk of Downs 1:110
Risk of amnio causing miscarriage 1:100

Possibly consider amnio?? That's the only way you'll know for sure.

Boober Fri 28-Aug-09 14:20:42

Also this is worth reading re the risks of amnio.

bevlin Fri 28-Aug-09 17:47:37

I haven't got time to read any other answers so sorry if this is a repeat. I had the nucal fold test privately (you have to pay in Edinburgh). Anyway she was very good at explaining it all which is what seems to have been missed with your appointment. Im 32 and the nucal fold average for my age (everything combined) should be roughly 1 in 620 and I got something like 1 in 540. I thought oh, why was that higher than it should be. Consultant said not to panic, that was just average and it was a good score and wouldn't recommend any further tests. She was very clear that I should not go for the NHS blood test for downs as the results can be very conflicting. NHS blood test is only something like 60% correct where as (as you said) the combined scan/blood/age etc is 95% accurate. Looking at the combined results are therefore more important than just the bloods. Id talk to the consultant who did your proper Nuchal fold and ask them what they think of that result and ask their advice.x

jardins Fri 28-Aug-09 19:14:45

Dear Mumtojennifer, I understand what you are going through and I hope to reassure you a little. I am currently pregnant with my third - having two very healthy children. I am forty years old. My nuchal trans at 12wk was really good: 1/344, which for my age was pretty wow and the specialist implied that with such a good score he would refrain from doing the tripple test. Here in France you are advised to meet a genetic specialist at the university hospital to discuss the amnio, states, etc, which we did. This was a totally confusing appointment. Although the specialist remained neutral I got the distinct impression she was urging me to do the amnio. I opted for the blood test instead and got my result back 2 days later: 1/189 - high risk. Now here's the confusing thing: my combined result was 1/1143. We had to make a decision re: amnio in 24 hrs based on 3 very conflicting numbers, which did not mean anything to me at all. It was horribly stressful. Fortunately my husband talked with the specialist who did the 12wk scan and he advised us to do a detailed scan at 18 wks, which still gave us a window for the amnio.

Yesterday I had this scan and the doctor was very reassuring. He even said 'if this baby's got DS then I'm changing jobs!' The point of all this is that we discussed the amnio and the triple test. He clearly stated that from 35 on a lot of his patients did NOT opt for the triple test because they knew their result would be bad. He also stated that although the stats were not published here in France FAR TOO MANY healthy fetuses were miscarried after a pointless amnio due to faulty triple test results.

Why don't you go for a 18 or 20 week scan? You will feel reassured. We knew this pregnancy was my last chance and we did not want to jeopardise it. However we were concerned about the impact a DS baby would have on our DC. (I hope this post doesn't offend anyone. Sorry. It's such a personal choice, isn't it and often based on fear and ignorance of the unknown.)

Please don't get too stressed. If the scan is done by a good specialist with excellent equipement it is 95% reliable. The specialist explained that the triple test procedure has not evolved in the past 10 yrs whereas the scan equipement has.

Good luck. Sorry this was such a waffly post.

LilianGish Fri 28-Aug-09 19:35:56

Poor you. I've been there and I know that however much you tell yourself the odds of the baby being OK are greater than it being Downs all you can think about is the fact that it might be. In my case that meant I had to to have the amnio (can't remember my precise odds, but something similar to you at the same age) - that's what I'm like, I just have to know! I also had mine in France though the consultant at the hospital painted quite the opposite picture to the previous poster - he said "We have to tell you the risk of miscarriage, but I can tell you we have never had a miscarriage as a result of an amnio at this hospital." DD was fine and two years later so was DS - also had an amnio with him and couldn't wait to be called for it on that occasion as I found it so reassuring. Good luck whatever you decide.

ilovesprouts Fri 28-Aug-09 19:39:23

mine was 1-250 !!

freudianslips Fri 28-Aug-09 20:17:50

I have just had the NT scan and was specifically advised NOT to have the NHS blood screening at 15/16 weeks. This is because the NT is far more sensitive and specific than the 15/16 week tests. This means that the NHS tests generate more false positives, and more worry, particularly for women above 35.

VERY VERY importantly, you state that the NT scan with bloods is 95% reliable. That is only if the bloods were taken on the same week as your NT scan. The hormones measured in this test are PAPP-A and HCG. Your bloods were taken at 15/16 weeks and the hormones measured in this test are AFP and HCG. So although you can combine the results of the two 12 week tests you can't combine the results of the 12 week scan with the 15 week blood tests. I am disappointed that none of your health care providers has explained this to you. I hope that you get some reassurance from this - in your position I'd try not to worry about the recent blood test and just aim to get a good, detailed 20 week scan to look for any soft markers. In fact, if you wanted to get a private scan done now they probably could set your mind at rest about some of these soft markers already e.g. heart, stomach, presence/absence of choroid plexus cysts, brain ventricles etc.

Hope to help. Remember: you really can't combine the results for these two tests, and the test that you had first - and got the better odds for - is the more accurate test.

TJ34 Fri 28-Aug-09 20:49:48

i have been told to avoid gassy foods. advice on what those are. i am 15wks pregnant

whomovedmychocolate Fri 28-Aug-09 21:06:26

I was given a 1 in 35 chance from the bloods but the amnio showed DS was fine. I have no advice for you other than to think carefully and go and talk to them, you should see a midwife counsellor first who will help you decide whether to have the amnio or not.

And if you are sure you want to test - just do it. Don't debate it with anyone, if you know it is right for you, don't even discuss it with people who will say 'well you know you could miscarry' - it's just not helpful.

QueenNeurosis Fri 28-Aug-09 21:19:07

I'm so sorry you find yourself in this hideous place. we had similar odds to you and I was distraught and yet the more I found out about the whole testing process the more angry I got. I decided that the best way for me to process the info was to remember that pregnancy carries a small risk. I took a test that served to prove nothing other that that my pregnancy had a small risk. Nothing I ddn't know already!

I decided not to have any further testing. There are so many undiagnosable (is that a word?) diagnosis that have greater challenges than Down's. We hung on until the 20 week scan (longest 6 weeks of my life) and took that as a clearer picture. My baby may still have Down's for all I know (due in 9 weeks) but baby will be absolutely perfect because baby's my baby. I know several genetically 'perfect' people who are so damaged because of their parents or circumstance etc.

Sorry that this is totally unscientific and probably offers little tangible reassurance but I will never have that test again!

jardins Sat 29-Aug-09 13:44:12

On reflection I agree with Whomovedmychocolate: people who claim 'you may well miscarry' are not helpful at all. I understand those who want to be sure and consequently go ahead with the amnio. I have a fear of amnio mainly because every medical bod has felt it necessary to warn me of the risk this pregnancy. Of course if my risk had been more severe I would simply have gone ahead with it.

cece Sat 29-Aug-09 13:51:54

I had a 1:50 result at the age of 40. I saw the consultant also and discussed the options. In the end I had no further testing as I was not prepared to terminate anyway so felt the risk associated with the amnio was too high.

That was my persoanl choice though and I was prepared to wait for the 22 week scan to find out more info.

Tillyscoutsmum Sat 29-Aug-09 13:56:55

Sorry you are going through this. My understanding is that an NT scan is much more accurate than the blood tests. There are so many factors that can affect the results of the blood tests - for example - if you've had any bleeding at all in your pregnancy , it can throw the results somewhat.

Join the discussion

Registering is free, easy, and means you can join in the discussion, watch threads, get discounts, win prizes and lots more.

Register now »

Already registered? Log in with: