My biggest fear

I know some people would say it would be to lose their baby before birth, miscarry or have a baby with a cleft lip or some type of heart condition. No, not for me. Mine is Down syndrome. I do not want my baby to have a genetic abnormality. I have enough on my plate. I have just completed and received results back with perfect results from that NIPT test. All good. But I see some people saying that isn’t 100%. Is there anything that is 100%? I need to know before I get to far along.