Signs of Down syndrome can be detected during a pregnancy ultrasound, too.
This article covers how ultrasounds and blood tests can reveal possible signs of Down syndrome.
It also covers diagnostic tests your healthcare provider may recommend.
Illustration by Verywell
While imaging tests can help indicate the possibility of Down syndrome, they cannot confirm it.
Likewise, a negative test does not rule out Down syndrome.
Again, further testing is needed to confirm the diagnosis.
Get our printable guide for your next healthcare provider’s appointment to help you ask the right questions.
Ultrasounds work by using sound waves to generate an image of the fetus.
These waves pose no risk to the mother or baby.
The first ultrasound is typically done in the first trimester, within 14 weeks of conception.
The second ultrasound is usually done between weeks 18 to 22 to confirm the fetus is developing normally.
How Accurate Is Ultrasound for Detecting Down Syndrome?
An ultrasound can’t diagnose Down syndrome definitively, but some ultrasound findings may suggest it.
If you have a negative result, you likely will not be offered follow-up diagnostic testing.
That said, most women with screen-positive results will have normal healthy babies.
This is an extremely personal decision and one that’s fraught with complex emotional and practical implications.
Or would knowing that you’re carrying a child with trisomy 21 cause you to have overwhelming anxiety?
Get our printable guide for your next healthcare provider’s appointment to help you ask the right questions.
Tissue retrieved with either of these procedures will bekaryotyped.
Under normal circumstances, there are 46 chromosomes organized in 23 pairs.
(This is why the clinical name for Down syndrome istrisomy 21.)
During pregnancy, karyotyping can be done by performing one of the following tests.
The insertion of the needle can be painful, but the procedure is very quick.
It usually takes a couple of weeks for full results from CVS testing to be finalized.
This means results can be available in a few days rather than a few weeks.
To confirm the diagnosis, a blood sample will be taken and used to create a karyotype.
Positive ultrasounds prompt further investigation with blood tests or amniocentesis, which may confirm a diagnosis.
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