Different results from Harmony and NHS test plus inconclusive gender outcome

[Farpavilions]

I am 40 and just over 12 weeks pregnant with my second. At 10 weeks, I did the Harmony test and was told I had a 1 in 10,000 chance of Down’s or the other two syndromes tested for.
I requested to know the gender but was told that, very unusually, the test was inconclusive. Apparently this happens in about 1% of cases.
Two weeks on, I did my NHS 12 week combined screening (scan/ blood test) and received a phone call to tell me I was at high risk of Down’s (1 in 60 chance). I understand this was based on levels of protein and hormone in my blood rather than the nuchal test.
I told them my Harmony results and they said I should be reassured as that test is supposedly more accurate and they would have advised me to take it as a next step, ahead of a CVS or amino (with risk of miscarriage) for a definitive answer.
Although the order in which I got the results is disconcerting, I am telling myself that the NHS test has identified a 1 in 60 probability of Down’s based on various factors including my age, while the Harmony test is telling me that I am not that one!
What is preying on my mind is the fact that the Harmony test also threw up the irregularity of the baby’s gender being unidentifiable. Have any of you also had an inconclusive result as to gender from this test and do you have any insights into what it means, if anything? Should I be worried that both tests are throwing up some other chromosomal irregularity or condition that is more difficult to identify than Down’s?
Would be really grateful for any insights as I don’t currently have the harmony of mind I am supposed to get from this test!

The NHS test I was offered was 2 step, bloods were taken for both at the same time. The first one was sent off and if there was a high probability, they would send off the second one for free for a more accurate result before offering anything invasive. Do they not still offer this? During my second pregnancy (after a late loss), I paid to have the second test done regardless of the result of the first one so I got the results on separate letters but at the same time. The first test showed something like 1:2500 for downs, the second said 1:50,000 and also stated the sex. I think the second test that I had (can’t remember name, sorry) is like the Harmony test that you had, so I would be reassured by those results.

However, because of the inconclusive sex, I’m not sure. 10 weeks is the earliest that it can be done so perhaps there was not enough fetal DNA, so I wonder if you could request the test to be repeated on the grounds that if there wasn’t enough DNA to confirm sex then you are not sure of the reliability of the screening results.

Not sure if I’ve been any help actually...

When we had the harmony test I was told that if there wasn’t enough fetal DNA that we might get an “inconclusive” gender result, because what the test is doing is looking for a Y chromosome. If they find one then it’s a boy, but if they don’t find a Y it’s a girl. However it is harder to prove the absence of something, if you see what I mean, so if there wasn’t much DNA available they can’t be super confident that there is definitely no Y.

If you can, it might be an idea to go back to the clinic who did your harmony test and just ask them to explain again what the inconclusive result means, for reassurance.

FWIW, we didn’t bother with the NHS test at all as the harmony is so much more accurate anyway, so I’d definitely set more store by your harmony test than the NHS one.

Harmony is more accurate for Down’s so I’m not sure why they did the NHS testing afterwards but if your Harmony result was

Will it make a difference to what you do (i.e. would you continue the pregnancy?).

I personally couldn't cope worrying for the rest of the pregnancy so would have an amino. Risk of miscarriage is very very low in healthy foetuses, the majority of miscarriages "caused" by amnios are of foetuses with genetic abnormalities found in the amniotic results.

Only you can say whether you can live with the uncertainty.

Relax!

The two tests work completely different ways. The NHS test is looking at bloods plus the nuchal fold thickness and part of the equation is your age (and weight although weight doesn’t affect the likelihood of any outcome it does need to be added in to calibrate the bloods.) so the test is indirect - it’s not looking at the dna it’s looking at the things that happen way downstream from there.

Because of your age you will start at a higher likelihood anyway and it only takes one slightly off measurement to really change the output.

The NIPT is looking directly at the DNA. It’s not uncommon to not isolate enough DNA from the sample, especially if you took the sample early. 10 weeks is early - I bet there just wasn’t enough material to say with confidence.

So the harmony is more accurate. You can contact the clinic who did it - sometimes they will repeat if there wasn’t enough dna.

Relax OP. As far as I'm aware the Harmony test is much more accurate than the NHS combined screening. So if you had just had your high risk result on the NHS test, the next step would have probably been the Harmony test which would have then ruled it out for you as I believe they don't give better odds than 1 in 10,000. It's because you've had the tests done in an usual order that it's causing you anxiety.

The reason for the inconclusive gender result will be not enough foetal DNA in your blood at the time it was taken.

You've had an excellent Harmony result- most people who had that would have opted out of the NHS screening anyway. Hope you're ok.

Thanks everyone for getting back to me and your support! This week I rang the clinic where I did the Harmony test to ask for further interpretation of the results. They contacted the hospital which arranged for me to see a foetal medical consultant. He said all fine. The Harmony test is more accurate and the inconclusive gender means nothing except, as previous poster said, that the sample of DNA was insufficient.
He said NHS result is a probability which is tipped by various factors including age and weight (BMI normal in my case) as well as the nuchal fold thickness (normal in my case) and hormone/ protein levels in the blood (slightly high/low in my case). Harmony is non-ageist and based on what they actually find in the blood.
So v relieved and don’t think will proceed with CVC or amino. They’ve also offered me an early anomaly scan when I can finally find out the gender and extra scans.
Not sure whether I am now being treated as high risk or low risk (Harmony lady was adamant I am a low risk pregnancy) but don’t very much care as long as the outcome good.
I can also now finally tell people!
Have a good weekend all

I know this thread hasn’t been listed on in a while. I was just wondering on the outcome of your pregnancy. I to had an inconclusive gender and low risk result. I’m struggling to find info and freaking out a bit