What do you make of these odds?

[Dustyblue]

Would love some perspective on this!

I'd decided that if I got dodgy odds on the combined screen I'd do an amnio. To me, these results look great for my advanced age of 41, but my gp is keen to get me in for an amnio asap. This is already causing problems, as I'm 16+ weeks and it looks like I won't be able to get in to the best hospital around for amnios for a few weeks. I live rural and there aren't many options, she's trying to get me in to the major city hospital a couple of hours away.

Free Beta-hCG: 1.4 MoM
PAPP A: 1.3 MoM
NT: 0.64 MoM

At the u/s when I was 13+2 the NT measured 1.3. Nasal bone present.

T21 risk 1 in 730
T18 risk

I suppose the first thing to know is would the results change anything? If you're unlucky and an amnio shows T21 would you terminate the pregnancy?

Not saying it's the right or wrong thing to do, but mihjt change things?

I'd seriously consider terminating for T21, so time is a factor.

I'm going to try to get in for an amnio, I was just surprised at the doc's urgency but I guess she has to cover her bases. I just have to hope I can get in sooner rather than later. I'm concerned that those odds won't exactly put me at the head of the queue.

Shame that I can't do a non-invasive blood test first, but she said it's next to pointless now... I'll have to read up on that, I'm not grasping why it wouldn't produce the same result as it would've weeks ago.

As far as I'm aware a NIPT would still give you a reliable result. Issue is that it will take 2 weeks to get that result. Amnio can be faster.

Why not call somewhere like the fetal medicine centre and ask their advice in regards to non-invasive testing? I know they include amnio in their price for harmony test if you come back as high risk and they're easy to get an appointment with.

1:730 looks pretty good to me. Having said that, I've just had the harmony test for DS3 because DS2 was diagnosed with T21 at birth after a combined test result of 1:600. At 39 now the consultant told me that from a standing start my odds were 1:67 for this pregnancy because of my age so I would have thought that your result is really encouraging. I was just one of the "unlucky" ones for whom the combined test isn't worth the paper it's written on! I say "unlucky" but with hindsight we are lucky because I am almost certain we would have terminated if we'd known in advance and DS2 is a total joy and the light of our lives (along with his equally amazing older brother!) Good luck and remember that you are almost certain to have good news. PS My Harmony results came back yesterday as 1:10,000 and combined test 1:1,300 so it looks like DS3 is fine!

Those figures look very positive to me - especially if your age was factored in.
Remember amino comes with a 1 in 100 risk of miscarriage. So with your results the amnio is statistically 7 x more likely to lead to a miscarriage then diagnose a chromosome problem.
Best of luck with it. 18 years ago I was given odds of 1/18 for T21. I was only 22. He is perfect

I am by no means a doc, however, after having dodgy hormone results I have had them explained in decent detail by specialist docs.

He told me you want all the MoMs to be as close to 1 as possible. Yours all look pretty close.

The risk of T21 in terms of bloods, you're looking at you hcg being double that of your Papp a. For T13 and T18 you're looking at low hcg and Papp a. I imagine looking at those numbers it's more your age that has effected the risk factor (sorry, don't know how to word that more sensitively!)

I would personally go for a private nipty test before an amnio. I'm also surprised it's your gp who is advising you, have you not been given a consultant appointment?

In my trust those figures would be considered low risk.

Btw just to let you know, you can have a tfmr up to term for trisomies. It's not pleasent and before 21 weeks is preferable (I had a tfmr at 22 weeks for T18) but please don't worry about time. The sooner the better but no one will stop you after 20 weeks (or even 24 weeks)

I'm quite shocked that your GP was "adamant" about the need for the amnio with a 1:730 result.

That's a low risk result!!

It's not no risk, no non-invasive test will give you that (although the Harmony/NIPT 1:10000 is as good as), but as someone who went through amnio testing with my last pregnancy aged 40, I would have been completely reassured by those numbers and wouldn't have considered further testing.

As pp have said, your chances of miscarriage because of amnio are far higher than your chances of having a baby with a chromosomal disorder. I wonder if your GP is hung up about your age - which would be wrong as this is part of the calculation and, going by your numbers, probably why your risk isn't in the thousands.

Your testing has shown that you're at far lower risk of T21 than the baseline for a woman your age. I really would have expected your GP to be pleased with this result. If he/she had been more positive would you be considering amnio now? It really is a good result.

Assuming a risk of miscarriage because of the amnio of 1:150 (debatable, but the published risk none the less), out of 730 pregnant women with exactly your risk profile who had an amnio 724 would find out their baby didn't have T21, 5 would have a miscarriage, 1 would find out their baby did have T21.

Sorry, that should be 729 would find out their baby didn't have T21, but 5 would miscarry because of the amnio.

Wow- my odds were much higher than that (1:259) and I still considered them pretty low. As my midwife said "Woul you back a horse at 250:1?"

I'm sorry this has caused you so much stress. There doesn't seem to be a need for an amnio based on these results.

I say this warmly, as the spouse of a GP: sometimes GPs get it wrong. It would appear that this is an example.

Of course, the sensible GPs seek expert advice when they don't know an answer! I have no idea why your GP hasn't done this.

I agree with pp that your results are low risk for your age, and I agree you should speak with an expert (and, in the meantime, perhaps Antenatal Results and Choices) before making any decisions or booking an amnio.