Check out the NCCI edits, 96820 is used to determine the best timing for inducing labor or to diagnose and evaluate fetal anemia. The Medicare status indicators also state it is included with a Q1 indicator which means it falls under , "STV-Packaged Codes". Therefore look at the status indicator on the codes you need to bill with it. Where is the location of service, this will play into correct coding as well.
OPPS Payment Status
Paid under OPPS; Addendum B displays APC assignments when services are separately payable.
Packaged APC payment if billed on the same date of service as a HCPCS code assigned status indicator "S", "T", or "V"
Composite APC payment if billed with specific combinations of services based on OPPS composite-specific payment criteria. Payment is packaged into a single payment for specific combinations of services.
In other circumstances, payment is made through a separate APC payment.