The Harmony Test is a type of non-invasive prenatal test (NIPT). The Harmony test assesses blood from the mother, looking at the baby’s DNA in her blood (analyses maternal serum for foetal DNA). It provides limited screening for chromosomes 21, 13, 18 and/or XY (sex chromosomes). The Harmony Test has a higher detection rate for trisomy 21 than combined first trimester screening (nuchal translucency scan plus maternal serum screening).
The Harmony Test identifies:
The Harmony Test, and all other forms of NIPT, is an advanced screening test rather than a diagnostic test. It does not detect all cases of trisomy 21, 18 or 13.
The Harmony Test also has a lower false positive rate than combined first trimester screening. This means that fewer women will need either chorionic villus sampling or amniocentesis to confirm a high risk result, when they actually have a normal baby unaffected by a chromosome problem. This exposes fewer women to the risk of miscarriage, since both chorionic villus sampling and amniocentesis are associated with a risk of miscarriage secondary to the procedure. The Harmony Test is a simple blood test with no risk to the foetus.
The Harmony Test can be performed after 10 weeks of pregnancy. It can be performed in both single and twin pregnancies, as well as IVF pregnancies. The Harmony Test can be performed at any stage during the pregnancy after 10 weeks’ especially if there are concerns raised after your morphology ultrasound at 18-20 weeks that increase your risks for trisomy 21, trisomy 18 or trisomy 13.
There are 2 ways that the Harmony Test is commonly used:
1. As a first line investigation.
This means you have the Harmony Test first (e.g. at 10-12 weeks’ pregnancy) and then come back for the nuchal translucency ultrasound / first trimester screening at 13 weeks’ gestation.
2. As contingency screening.
This means you have the nuchal translucency ultrasound / first trimester screening first and then decide on the need for further testing depending on your adjusted risks. You may then opt to have either the Harmony Test (NIPT) or prenatal diagnostic testing with CVS/amniocentesis, depending on how much additional information you desire about the baby’s chromosomes.
Our doctor will contact you directly once the results of the Harmony Test have returned. This usually takes 7 days. Sometimes the initial sample of your blood may not give a result. This is related to technical factors and does not mean there is a problem with your baby. It is more likely for this to occur if you are earlier in your pregnancy (such as 10 weeks’ pregnancy, rather than 13 weeks’ pregnancy) or due to factors such as increased maternal weight. If this happens, we will call you to organise the collection of another sample of your blood, at no additional cost. For most patients, this repeat sample will give a result.
If the Harmony Test shows a “high risk” result for a chromosome problem involving chromosomes 21, 13, 18, X or Y, this does not mean that your baby definitely has one of these defects. You will need to have diagnostic testing with either chorionic villus sampling or amniocentesis to confirm this diagnosis before making decisions about your pregnancy.
If the Harmony Test shows a “low risk” result (risk less than 1 in 10,000), this means your baby is unlikely to have a chromosome problem involving chromosomes 21, 13, 18, X or Y. But the Harmony Test does not detect all cases of chromosome abnormalities or genetic defects. If ultrasounds of your baby detect structural abnormalities or other concerning features, your doctor may suggest additional testing such as amniocentesis, even if the results of the Harmony Test were reassuring.
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