What is Fetal Fraction?

Honesty • Engaged with our miracle daughter after being told I could not get pregnant.

I had the panorama blood screen done and I received the results online today. Besides seeing that it's listed as low risk, I can't find anything that makes sense to me on why it's low risk and what the results really mean.

Have any of you had this test done and can tell me some about it? What do the numbers under prior risk mean? What does the fetal fraction percent mean?