advice on blood results please

[BabyBaby123]

I've just got my blood test results and they hav come back as low risk for downs syndrome and spina bifida, 1 in 4,300.
Can anyone just explain these results for me?
I can't remember with my first dc what my results were - but my second was a result of less than 1 in 50,000 (she's now 5)
Can anyone explain why they have shot up so much? What are they actually testing? I'm confused.

I am 28 btw.

Thanks.

Your results mean that if you were to have 4,300 babies (!) 1 would have downs or Spina Bifida.

The results are very good. They are age dependant. So with the same blood test results in a 23yo the results may wel be 1 in 50,000.

The important thing is that 1 in 4,300 is a very good result.

Yes this is to do with your age and a few other things. If you were at high risk, the midwife would have called to dicuss your results. I just had 1:25 risk of Downs etc, and had Amnio last week, luckily this came back normal. So 1:4,300 is a good result

I agree, it's just your maternal age. My result aged 26 was 1/1600 which was very good/of no concern so nothing to worry about.

ok, thanks very much just seems a massive difference between a 23 and a 28 year old's results! Does anyone know what the averages are for each age?

half way down this page is a table showing hte risk based on age alone. This does not take into account the blood test results.

HTTH

Is anyone else wondering how OP can possibly have the same risk for DS and spina bifida, which are two completely different conditions?

what do you mean? I have had the combined blood test - the letter states 'low risk of you having a baby with Downs Syndrome or spina bifida'

The result given is for Downs Syndrome - it doesn't mention Spina bifida again

Thanks for that DoNot

I think it is the risk of a baby having (spina bidia OR downs syndrome). i.e. 4299 babies will have neither. 1 baby will have downs or spina bifida.

What I meant was that tests look for different substances in blood for spina bifida and DS.

high AFP >> high risk of spina bifida
low AFP & estriol, high hCG and inhibin-A >> high risk of Down's Syndrome

It seems a bit irrational to give a single risk for both, given that high risk of spina bifida seems to point to low risk of DS and vice versa.

I think it is more a point of

high AFP >> high risk of spina bifida
medium AFP - low risk of both.
low AFP & estriol, high hCG and inhibin-A >> high risk of Down's Syndrome

They probably give the highest risk result.

No. As I said, low AFP >> high risk of Down's, which also points at low risk of spina bifida.

It's not just AFP that points to opposite directions in risk for spina bifida and DS. There is also maternal age.

younger mother >> lower risk of DS
younger (esp teenage) mother >> higher risk of spina bifida

I studied a bit of statistics, and can't imagine how (or why) two different conditions (one genetic, one developmental) would have a single statistical risk factor.

Low, high, medium is one thing, a specific number like 1/4,300 is another.

the letter I got for my last baby (5 + years ago) was the same - is it not the same testing everywhere?

Everyone has been reassuring but me and dp are still a bit worried - especially as it's a big difference from dd - does the fact you have a higher risk (but still low risk, I know...) indicate there could be some other problem? or is it just for those two conditions?

And what is the nuchal scan for? Downs or SB? Ours was 1.6 I think at 12 + weeks....

Please do not worry.

It does not matter what your results were 5 years ago.

Your results for this baby indicate a risk factor of 1:4,300.

As I said earlier if you were to have 4,300 babies (along with having no pelvic floor left!) only 1 of them would have downs/spina.

If you have another baby - your results could be 1 in 50,000 again. They could be 1:4300 again or they could be 1:23. each result has to be interpretted independantly.

Honestly 1 in 4300 is a great result.

Thanks

here you go here is another chart of risk v maternal age.

As you are 28 your risk should be 1 in 1100 (if you idn't know the blood test results). Your blood results must be very favourable because your risk is calculated to be 1 in 4300 which is lower risk than it "should" be.

Nuchal is for Down's Syndrome. 1.6 is a good measurement.