Why did my NIPT fail?

A failed, no-call or inconclusive result usually means there was not enough placental DNA in the sample for the laboratory to analyse reliably. It does not mean something is wrong with your baby. The two best-recognised reasons, per ACMG, are a higher body mass index and testing early in pregnancy, particularly before 10 weeks. In twin pregnancies, no-calls are also more common, because laboratories generally judge adequacy by the lower of the two fetal fractions. Occasionally the cause is technical — sample handling, transport, or laboratory processing. What usually happens next is a repeat sample at a slightly later gestation, and most women get a valid result second time. If repeat testing also fails, you should be offered diagnostic testing rather than left without information. ACMG specifies that counselling after an uninformative result should include the offer of diagnostic testing. One thing to raise with your obstetrician rather than worry about alone: low fetal fraction has been associated with some pregnancy complications, though ACMG notes that definitive rates and any surveillance protocol have not been established. It is a reason for your doctor to be aware rather than a reason to assume a problem. Ask whether you will be charged for a repeat test. Many laboratories redraw without additional cost, but policies differ and it is worth establishing before the second sample.