Down's Syndrome - accuracy of screening?

[Caezzybe]

Hi everyone,

Reading through the threads on here, I've noticed that the screening tests for Down's appear to be somewhat inaccurate (there seem to be a lot of false positives and the odd false negative). I just wondered how many people are getting false results (and correct results) and what they were. Are you in one of the following categories and if so, could you please post in this thread with what happened and what your risk was estimated as? Also, it would be interesting to know your age and if anything was picked up at your 20 week scan.

Was your result:

High risk and unaffected baby
High risk and Down's baby
High risk and other genetic problem
High risk and other problems (please let us know what issues)
Low risk and Down's baby
Low risk and other genetic problem

I was low risk (1 in 560) with a NT measurement of 1.9mm. The 20 week scan also came back normal (no heart problems detected, no mention of any issues with nasal bone) and I had a baby with Down's Syndrome, diagnosed the day after he was born. I'm an older mother (41 years old).

 

[Szaffi]

Truth be told, it's hard to call it inaccurate, as it only gives odds - even with 1:6 you can end up being the five unaffected and with 1:10000 still be the 1.

But I agree that the usefulness of the test is dubious.

My result was 1:235 (so high risk) combined result, as nuchal test was normal (1.3 mm at 10 w +5 d). Triple test alone (15 w + 0) gave me odds of 1:159. A week later (16w+6d) I redid the test, and it gave me 1:375 (so low risk). I was 33 at the time of birth.

Had detailed scans on week 17 (private) and 20 (normal) - no markers or any abnormalities were detected. I went on to have a baby without DS.

ETA: Caezzy - your son is gorgeous.

 

[louise85]

Hi there I was high risk and unaffected baby.

I am 24. My odds were 1:89 after a nuchal measurement of over 3mm. I didn't have amnio or cvs. I had detailed scans at 16 and 20 weekswith no other markers and also a heart scan were everything was fine.

Agreed your son is gorgeous

xxx

 

[midori1999]

I was 27 when I had my son and my odds were 1 in more than 10,000. He was born with Downs. He has two holes in his heart which were not detected at hos 20 week scan. (that said, one of my daughters had talipes and this was only picked up the day before she was born, despite me having had around 20 scans during my pregnancy, and even then they said it was on her left foot when it was her right, so I don't hold that much faith in scans!)

Almost everyone I know with a child with Downs had a 'false negative' and considering over 90% of those who find out they are carrying a baby with Downs do decide to terminate, I suspect this is a true picture and most babies born with Downs are cases where it is not detected during pregnancy.

 

[harpixie]

Hi, I'm 37 and had a baby girl born with downs syndrome 5 weeks ago. It was a complete shock and still is. Had the triple test which came back low risk. Was told by the midwife in after she was born that I was my risk was 1 in 247. Nothing showed up at the 20 week scan at all. She's had an echo test on her heart and we're just waiting for the results from this.

 

[genies girl]

i was very high risk nuchal came back 1 in 16 , we decided no further tests just scans as we wouldnt change anything .
20 week scan showed echogenic focus in heart but no soft markers nasal bone was present ect but risk was altered to 1 in 10 .
my other twins risk was 1 in 350 both were born six weeks ago and are unafected by downs

 

[genies girl]

forgot to say im 30

 

[Caezzybe]

Hi, I'm 37 and had a baby girl born with downs syndrome 5 weeks ago. It was a complete shock and still is. Had the triple test which came back low risk. Was told by the midwife in after she was born that I was my risk was 1 in 247. Nothing showed up at the 20 week scan at all. She's had an echo test on her heart and we're just waiting for the results from this.

Good luck for the results of your daughter's ECG, Logan has his heart tested on 18th October and will be 8 weeks old then.

 

[harpixie]

Thanks Caezzybe. Hope you're little boy's scan is ok

 

[Emx]

Hi - Im 37 and was given a 1-50 risk after Nuchal Scan of over 3mm - my bloods also increased the risk.. We declined a CVS or amnio as the results wouldnt have made us choose any differently about how the pregnancy progressed. My 20 week scan showed no abnormalities and an excellent sonographer at a 32 week placenta check scan told me she was 'very sure' Lani didnt have DS.. and she was right..

I am TTC 2 early next year - and assuming all goes well, I wont be having any screening tests other than the anomoly scan at 20 weeks x

 

[A3my]

Hi, my baby was a high risk and unaffected baby.

His NT measurement was 4.8mm and my combined risk was 1:18 I had a CVS which was clear and cardiac scans which were clear. I was 31 when I had him.

Ditto what everyone else says, your baby is a vary handsome little fella

 

[Deli]

Hi. I have six children, my four middle children (all girls) have come back low risk and have been unaffected.

My son is nearly 15 and with his pregnancy I was given a 1:91 risk (I was just 22 at the time). At that time they didn't do nuchal fold scanning and CVS/Amnio still carried quite a high miscarriage risk. He was born fine but had to go straight to SCBU as he showed facial features indicative of Downs. However, he had a chromosone test and all was normal. His appearance is normal now too.

My latest baby is 8 weeks old and I was just about 37 when he was born. I didn't find out I was pregnant with him til 16 weeks so missed the nuchal fold scanning test. I had the quadruple blood test and was given a risk of 1:250, slightly higher than normal for my age. As far as I could see it, he was a blessing that I wasn't expecting so refused any further diagnostic tests or scans for soft markers. He was born unaffected by Downs.

As everyone else has said, your baby is beautiful. Congratulations.

 

[Deli]

I should add that research has shown that vegetarians have a slightly higher false positive rate.

 

[Caezzybe]

I should add that research has shown that vegetarians have a slightly higher false positive rate.

It's interesting you should say that as I was vegetarian at the beginning of my pregnancy (up until about 10 weeks) and got a false negative.

 

[Deli]

I should add that research has shown that vegetarians have a slightly higher false positive rate.

It's interesting you should say that as I was vegetarian at the beginning of my pregnancy (up until about 10 weeks) and got a false negative.

Oh, maybe being vegetarian affects the result in general then. I'm not sure now!

My sister lives in New Zealand and when she had her boys 8 years ago, this test was not routinely offered due to its inaccuracy. I'm not sure if they still offer it now.

 

[SwissMiss]

I'm not sure I should be posting as I haven't had my lil man yet, but I came back high risk after my 16wk bloods (1:80) and had an amnio - everything is/was fine. I'm 32.

Congrats on your sweet lil guy, he's beautiful!