12 week nuchal scans - NHS & private - very different results. Any experience?

[PumaGirl]

I had two 12 weeks scans this week, one day after the other.

Got Downs odds of 1:1450 at the private one and 1:460 for the NHS one. Quite a difference.

Anybody had a similar experience?

Am thinking that I might get the NHS one re-done.

Any thoughts?

why did you go for both?

did both do a blood test too?

I had a private scan done after my NHS one following a very high result that i didn't trust for various reasons. The difference between them was massive. This i think was down to a couple of reasons, firstly at the private scan they combined it with the blood test (was not offered at the NHS scan) also the private one seemed to be more detailed, checking specific things to do with the heart etc (not sure what i'm afraid)
I was reassured enough by the private one the leave it at that and declined any further investigations from the NHS, amnio etc. Went on the have a healthy baby who is sitting here 'reading' a book to herself at the moment.

I doubt the NHS will re-do this, especially given that their results are not what they consider 'high risk'.

You could get the private one done again but what do you think this will tell you? Scanning isn't an exact science, its all just a rough steer and none of it means you won't have a child affected by a chromosonal abnormality.

If it were me, I would go with the 1:460 and decide my next step from there - I don't think this is low; Are you thinking that if this is the 'right' odds you will look at CVS/Amnio?

Having had a private scan with a blood test ( which is what I assume you had ?) - as far as I understand the one with the blood test is the more accurate so I would go with that one.
I really don't see the point of getting the NHS one re done even if they would do it. Why do you think that would be helpful ?

Thanks for your comments.

Both of the tests were the combined one (blood and scan) but I have to say that the private one was more detailed (included nasal bone etc.).

Decided to do the private as well as NHS as it was recommended by my GP because I was feeling nervous about my age (over 40).

Will probably go down the lines of stickybean's experience - as in who do you trust more.

Aware that these tests are not an exact science but having a similar result makes decisions about further investigation slightly easier.

Take your points about an NHS re-do not being approved and possibly not productive.

Very interesting to hear from those who've had a similar experience though - thanks again.

I doubt that the NHS will want to re-do the nuchal, especially as the reason that you want it re-done is because you also had a private scan - they obviously think one was sufficient, so probably wont want to give you a third.

What would you do if you assume that the risk is 1:460? Would you have an amnio at that level of risk?

The highest risk given is still only a 0.2% risk.

In the wide range of results from 1:2 to 1:tens of thousands the 2 results you have been given are very very close and may just be different because the 'formula' used to calculate the risk may have been worked out using different populations (the blood markers differ very slightly in different populations).
Both results are very good for someone over 40 (as the maternal age is heavily weighted in the calculation, you need to have extremely good NT and blood markers to get a 'low' risk result).

And I agree that it is extremely unlikely that you would be able to get a re-scan on the NHS, more likely to get a lecture on why you had an NHS scan in the first place if you were going to have a private one.
I had a private scan with one of my pgs before it was available on the NHS, I subsequently had the second trimester blood test (despite me telling them not to do it) which came up high risk but all I got was a lecture from the midwife about only having 1 test - luckily I know how the testing works and was happy to ignore the NHS high risk result as my NT+blood result was fine.

You've answered your own question,'the private one was more detailed' hence the slightly different result, both results are fine so why worry, I had a result of 1:12 and was still ok.

0.2% - good point!

Millarkie - thanks for your detailed response - very useful.

Glad your 1:12 worked out well Danthe4th.

Feeling better already!

Thanks all.