So, there’s a series of non-invasive prenatal testing that you can have done.
Firstly there is a blood test between 10 and 13 weeks that measures human chorionic gonadotrophin (HCG) and pregnancy- associated plasma protein (PAPP-A). This together with the nuchal translucency scan at 11-13 weeks is put into some sort of formula and out spits the result. You are either at higher risk (I think < 1:200) or lower risk (> 1:200 – don’t quote me on the figures).
There’s also chorionic villus sampling and amniocentesis, but these are invasive and increase the risk of miscarriage.
And then there’s the Harmony test – a new test, that detects free foetal DNA in maternal blood and measures for chromosomal abnormalities.This is ideally collected at 10 weeks of gestation, however, it is private and costs $450. So it’s not routine (although it may get there).
However, I’m a bit hypervigilent in this pregnancy, and I’d heard about this test, on, of all places, the Nature podcast back in about 2008. I was surprised by how rapidly it became commercially available. I had friends who had a baby around 2012, when my son was born, and they were part of trials (so got it for free). Now it is offered but commercially.
The ultrasonographer at the 12 weeks scan seemed surprised that we needed to get the nuchal translucency (which is difficult to get) given we already were doing the Harmony, but she bravely went ahead and measured it. She told me it was within normal limits at the scan.
However, when I went for a check up with Dr Miscarriage last week, she said my prenatal screening had put me at higher risk BUT because we had already done the Harmony, which was negative, my risk of a chromosomal abnormality is < 1:10,000 now.
Which is really excellent. Being anxious this time has actually paid off for once. Normally Dr Miscarriage would need to send me to counselling with a high risk result, and then they’d “beg me to pay for the Harmony” and if I couldn’t I’d be in for an amniocentesis or CV sampling.
With all the weeks of stress that would involve (Harmony takes at least two weeks for the results to come back).
So phew! All is well AND I missed having several weeks of worry. That is well worth $450!