Nuchal Translucency - to test or not?

[RuckAndRoll]

I wonder if anyone can help my clear my head on Down's Syndrome tests. This may be a bit of a brain dump - my apologies - I hope someone can make sense of my thoughts.

DH and I have discussed this in depth and we've agreed if the baby has Down's it will make no difference to us and we will progress with the pregnancy and love the child the same.

So, we thought, no need for the nuchal translucency scan as anything they need to pick up for my/babies health will be picked up at the normal 20 week scan.

Also I'm a panic-er and analyser so a risk factor would just be a nightmare for me.

Now I'm thinking, do the drs need the nuchal scan to adequately assess the baby before birth and keep it safe before/during/after birth?

Basically I think I'm asking, am I putting my baby at risk by not getting the nuchal scan done just to keep DH and I calmer over the next few weeks? Would it be better to give the drs the opportunity of finding out earlier on or can they pick up all they need at the 20 week scan?

I hope someone can work out what I'm asking and help me a bit. Thanks in advance

It's a common misunderstanding that the scan at 12 weeks is only for Down syndrome screening. It depends on your NHS trust, but the nuchal fold is often not the only thing they look for - the state of the organs can also be assessed.

But the 12 week scan does not just assess for Down syndrome but also for other chromosomal abnormalities (Edwards syndrome, Patau's syndrome and Turner's). It can also detect spinal abnormalities such as spina bifida, brain abnormalities and a condition called fetal hydrops. A increased nuchal fold can also indicate heart problems/defects. Some of these conditions will be incompatible with life, meaning that your baby will die in the womb or at birth. Some incidences of these conditions may be manageable, and able to be treated, although your baby's quality of life may be affected.

It depends on you whether you would prefer not to know whether any of these affect your baby until the 20 week scan.

Thanks ghislaine.

What I'm trying to avoid is any sort of '1 in x' chance of Downs as I know it would mess with my head and I can't cope with that. If they can say 'your baby has problem x' that's fine, tell me.

DH and I are going to sit down again tonight and go through all the info we have again and see if we can make sense of it all.

I'm afraid that if they pick up on a problem, it's not always clear-cut what it is. I do speak from experience. Basically the 12 wk scan is primarily to pick up on t21, the most common pg issue, but there are stacks of other things it can pick up too. When it comes to the 20wk scan, the baby has developed more so new things can be picked up at that stage that wouldn't be there at the 12wk scan. It really depends on what you'd do if there was a problem. If neither of you would want to terminate (typically surgical before 14wks and labour & delivery after that) whatever the issue (whether fatal or non-fatal but with disabilities) then the scans would act as an 'FYI' . Aside from developmental abnormalities, they'll be able to tell you if you are expecting twins or more, or even check that your baby has somehow died/miscarried without you showing any symptoms. Anyway, I hope that's some food for thought.

The paperwork from the hospital is quite simplistic and says they will do a 'dating scan' and a 'Down's Syndrome scan'. It's only the Downs one we are thinking of refusing.

I suppose I just need to get used to the lifetime of guilt, confusion and 'am I doing the right thing'

Thanks mb

You could say exactly that to the sonographer, perhaps? Something along the lines of "please tell me if there are any abnormalities but not my risk result for T21"? At both my scans I got the result after the scan as I had to wait for blood results to be analysed. You should also think about whether you'd want to know at that stage whether your baby did have T21.

Hi ruck you can have the scan and just say that you don't want the nuchal test or blood test results - it might be that you can refuse the blood tests too, although they will need to test you for blood group and other basics. I know other people have done this - someone else might come along soon to explain. I can see why you'd not want the statistic result - they are a bit meaningless, although obviously if you get a 100% positive result for Downs you might want to know, so that you can prepare for that when babe arrives.

Good luck with your decision - also your midwife should be able to advise you how you have the scan but not the test results...

Thanks again ghislaine & booboo

I think you've got exactly what I want, happy to know if they find abnormalities (well not happy, but you know what I mean) but I don't want a statistical risk factors. I'm a scientist and work with risk factors every day so would spend far too long analysing the results if told them.

I see the midwife for my booking in appointment on Monday so will chat to her then.

I didn't have it with either of my pregnancies. My opinion is that it has a 1 in 20 false positive rate against something that is fairly unlikely. It does as some say potentially show up issues that may not show up until 20 weeks but it equally worries many people half to death over nothing. The latter is more likely by far statistically.

You can ask to not be told your 1 in x risk factors as that's what I did. I don't know about your area bit where I am they measure nuchal regardless of if you want Down's syndrome test and they will tell you if there's an increase as can point to other problems, however you don't need to have the blood test which is a contributing factor to your 2 in x chance. Hope that makes sense!

For couples who wouldnt terminate for Down Syndrome the main medical advantage of knowing about it would be to have a fetal echo to exclude heart defects as 40pc of babies with DS have heart defects. Heart defects are commoner than DS anyway so why not have a fetal cardiac scan as knowing about a fetal heart problem (and 50pc are missed at Anomaly Scan) would help optimise your care.

I didn't have the test but I was told by the mw that the sonographer had a duty of care to tell me if she saw anything abnormal in my scan. They just didn't take a Nuchal measurement.