Noninvasive prenatal testing as first tier-aneuplody screening: the role of ultrasound in the post-test counseling of positive results.

For educational purposes, in order to show the importance of the " I a priori i risk" we have selected 4 cases of false positive NIPT results, two of trisomy 18 and two of trisomy 13, with different maternal ages. To the Editors, Noninvasive prenatal testing (NIPT) is the most effective prenatal screening test for trisomy 21 and other prevalent aneuploidies like trisomy 18 and 13 and it can be performed from 9 or 10 weeks of gestation [[1]]. [Extracted from the article]