First Off Let Your Doc Know Ur On Gear Because It's Kinda Important To Your Health When Your On The Table Cause Of The Drugs Used.the Blood You Gave I Think Will Be Given Back To You If Needed During Your Surgery . Are You Having A Complete Ball And Socket Replacement Or Just Hip Joint?anyway They Send It To A Blood Bank Where It's Tagged,filtered And Stored For Your Use Only. They Don't Check For anabolic androgenic steroids So Don't Worry About That . But,it's A Good To Let Your Doc Know Your Using Or "used" In The Past Few Months Because Some Of The Drugs They Push Into You Such As, Clotting Factors Or Blood Pressure Meds Can Be Effected By The Higher Red Blood Cell Count That Aas Create In Your Blood Stream . Besides The Whole Doctor/patient Private Thing Going For You Anyway .