In fetuses with trisomy 21, 18, and 13 and triploidy, the maxilla is significantly shorter, but the difference is only settled, so that it is unlikely that the maxilla length will play a role in second and third screening for aneuploidy.

In aneuploid fetuses, the SFD is smaller than in their euploid counterparts. However, for a false-positive rate of 5%, the detection rate of trisomy 21 is only 26%. Therefore, using the method we have proposed, it is unlikely that this marker will play a major role in second- and third-trimester screening for aneuploidy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.