do you buy a mattress pad for a breathable mattress ?

Nadia • FTM , due 12/23 with baby boy
I bought the lullaby earth breeze crib mattress which is suppose to be breathable and waterproof .
But do you use a mattress pad cover ? I feel like if I do , it takes away from the breathable part . Im still using a sheet over it but I'm confused on if I should or shouldn't 
Any advice greatly appreciated