This test for the most common chromosome abnormalities combines the result of a blood test and the ultrasound measurements taken at 12-14 weeks.
The blood test is done between 9 and 14 weeks (preferably at the earlier end of this range). The ultrasound is done between 11.5 and 14 weeks (preferably between 12 and 13 weeks). Together with information about the mother’s pregnancy history, the test calculates the chance of Trisomy 21 (Down syndrome), Trisomy 18 and Trisomy 13 being present.
The test result is high probability in about 4% of pregnancies. An invasive test (CVS or amniocentesis) is required to confirm whether the abnormality is truly present, as about 95% of the time, the baby will actually be healthy.
Some people may choose to have NIPT as the next step before considering invasive testing. The nuchal test detects about 85-90% of pregnancies affected by Trisomy 21, so a low probability result for this test is not as reassuring as a low probability NIPT result, which excludes over 99% of Trisomy 21 cases. It is possible to use the cFTS to make estimations of the chance of preeclampsia or preterm birth. More information about cFTS can be found via some of the sites links in our Resources page.
QDOS Ultrasound provides specialist obstetric and gynaecology ultrasound performed by highly experienced and motivated doctors and sonographers. The rooms are purpose-built, located on the ground floor at 12 Connolly Street, West Leederville, at the rear of Connolly House, which is on the corner of Connolly and Cambridge Streets, opposite SJOG Hospital Subiaco.
Pregnancy
Gynaecology
Contact
Address
12 Connolly St, West Leederville
PERTH – Western Australia 6007
Monday – Friday
8:00 am – 4:45 pm
(strictly by appointment only)
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