NT declined and Downs Syndrome not picked up at 20 week scan.

[HANIEL]

Is there anyone who declined the NT and had a normal anomaly scan but had a baby with Downs Syndrome. I declined the NT as we would not terminate, and I had a normal anomaly scan with an NHS experienced sonographer. I can't help but wonder, is everything ok. The information the health care professionals give is that this can be missed at the anomaly but how often. Anyone like to share their experiences?

My midwife gave me a leaflet with the statistics on it - if you ask for the info your midwife should be able to give it to you. I have thrown it away now as it was just making my brain hurt, but I've got a vague idea that about 10% of the babies born with Downs Syndrome were not detected before birth - could be wrong though, it was a smallish number but not tiny IYSWIM.

Friend had a very low risk given from the 12 weeks nuchal fold scan and had a baby with DS.

www.babycentre.co.uk/pregnancy/antenatalhealth/scans/nuchalscan/. This link gives a bit more info on the detection rate of NT scans

www.babycentre.co.uk/pregnancy/antenatalhealth/scans/nuchalscan/

Slightly different circs but I had a DS with downs. I had a normal NT and a normal anomally scan, although it was picked up in later routine scan. I know there is at least on other woman on MN who has had a very similar experience.

If you are very concerned is it worth requesting another scan?

My niece has downs syndrome and it wasn't picked up before birth. It was before the days of nuchal fold scans but she had the normal ultrasounds. My niece is a teenager so I expect the picture quality has improved since then.

I can't give figures but certainly not all Downs are detected via non-invasive testing, as is explained in the leaflets. The only way to know for sure currently is for everyone to have an amnio which would expose all babies to a hazardous test that can lead to miscarriage. But I'd like to make some observations
:we obsess on Downs because we have an (imperfect) test that we are asked to accept or decline. But there are other serious conditions that cannot be screened for antenatally and we tend not to think about them because no screening is offered, other learning disabilities for instance.
: those accepting screening with a low-risk result are not getting a "no risk" result. Some of them will have an affected baby. Some will feel cheated because they accepted screening and their baby was not detected
:anomaly uss can pick up major structural abnormalities but not all Downs babies have these. Some are healthy babies.

A 20 week scan is not intended to provide an effective screening method for Down's syndrome, 50% of babies with Down's syndrome will look entirely normal on such a scan. The cases picked up on later scan will typically either have a cluster of soft ultrasound markers or a more major abnormality.
The Combined NT and quadruple/triple blood tests provide far more effective means of screening/identifying Down's syndrome pregnancies. The latter are however 'screening tests' and not 'diagnostic tests' they will have an identified detection rate, false positive and a false negative rate ie. they are not infallible!

I know of a lady who had a DS child which wasn't diagnosed (this was in last few years too) - total shock to her and her husband.

NT scan etc only gives you risk of probability - in 100000:1 odds you could still be the "1" Alternatively in 12:1 odds you could be one of the "12".
The only way you will know for sure though is with either a CVS or an Amnio (believe you can stil have amnios quite late into pregnancy).

I took the view that i wouldn't terminate so not to worry about it too much. I did lots of reading and stuff and unless there are severe complications (that poss wld show in a scan as they are heart related etc) the first 12 mths were unlikely to be hugely diff than a child without downs so would have time to adjust...I could be wrong but that was the view i took, I had a VERY high risk and was given several talkings to by medical staff but I just said - I wouldn't terminate so what is the point? and they couldn't answer me so i went for it and my daughter is not downs.