New risk-free blood test for mums-to-be that flags up any potential abnormalities
Published 04/04/2013 | 04:20
Pregnant women across Northern Ireland can now find out whether their baby will be born with a range of genetic conditions without the risk of miscarriage.
Chromosomal abnormalities are rare, but increasingly parents want to know if there are any problems as early as possible.
A new blood test is being offered that is free of the potential risks associated with existing tests such as amniocentesis and chorionic villus sampling (CVS) tests.
One in 100 women who opt for these diagnostic procedures – which involve inserting a needle into the womb – will suffer a miscarriage or dangerously early labour. Dr Samina Dornan, the doctor bringing the test to Northern Ireland, said: "This test is a positive choice option as it allows mothers to prepare for what lies ahead, and, in the vast majority of cases, they are going to find out that they definitely are carrying a normal baby.
"There are so many benefits to this blood test – the most important is the number of babies we can save because it is not invasive testing.
"Even if we save one baby's life, it is an incredible thing."
Unlike the amniocentesis or CVS tests, a blood sample from the mother is all that is required for the 'Harmony' blood test.
This is then sent to a laboratory in San Jose in the US where chromosome levels are analysed and, in less than a fortnight, the mum-to-be will find out whether her baby has Down's syndrome, Edwards syndrome or Patau syndrome.
Dr Dornan, a consultant obstetrician and gynaecologist, continued: "Most mums will find out there are no problems so we are bringing them huge satisfaction and they can enjoy the rest of their pregnancy.
"The test, which has never had any false positives, can be performed from a sample of the mother's blood taken anytime after 10 weeks gestation and a normal result guarantees 100% that the baby has normal chromosomes.
"If the test identifies any problems, the mother and the family then has time to come to terms with this, they have recovered from the initial shock by the time baby arrives and the birth is a beautiful thing," Dr Dornan added.
Under the health service, potential health concerns in unborn babies are flagged up at a scan performed at 20 weeks, while some maternity units also offer a maternal blood test 16 weeks into the pregnancy.
However, these are not 100% accurate, so an amniocentesis or CVS test should be carried out for a definite diagnosis.
The Harmony blood test for expectant mothers is not available on the health service but is being offered through the 3fivetwo private clinic in Belfast.