Maternit21 and Harmony Testing?

Gabriela • First time mom. 23. Due 06.26.17
I'm thinking of having the Maternit21 or Harmony test that check for Down syndrome and sex of baby. 
I am under my mother's insurance and she has Federal BlueCross Blueshield. Anyone with this insurance, have to pay extra or does it cover it.
I am 23 and I am not high risk. I am currently 10 weeks.