Introduction
Non-invasive prenatal testing (NIPT) is a revolutionary screening method for pregnancies considered at high risk of aneuploidy. NIPT has been largely embraced by women and healthcare providers for its superior detection rate for aneuploidy over the combined first trimester screening (cFTS).
Methods
An audit was conducted on all NIPTs at the Maternal Fetal Medicine unit of the Royal Brisbane and Women’s Hospital between October 2015 and April 2018. Patients’ details and test results were obtained through private pathology providers. Data extraction was completed with respect to patient characteristics, obstetric and antenatal history, indications, results and invasive procedures if performed.
Results
NIPT screening was performed in 90 women (91 tests) with a mean age of 33.4 years and a mean BMI of 24.3. The most common reason for referral was a high risk cFTS (44.0%) followed by abnormal findings on the morphology scan (14.3%), previously confirmed trisomies (7.69%) and as a screening alternative for women who missed the cFTS (4.40%). NIPT returned high risk in only one case for trisomy 21 with no false positive or false negative results. Amniocentesis was performed in 6.59% of cases.
Discussion
The uptake of NIPT is popular amongst high risk pregnancies and has increased secondary to reducing costs of testing. Our audit of NIPT provides insight into the various indications for the test and reflects patients’ screening preferences.