ANSWER:
If these are your normal vaginal discharges, you don’t need to wash them off to pray nor to perform wudhu as these are not najis.
If these are other than your vaginal discharges such as the result of infection, this is najis and requires that you only wash the affected area once the athan is called and make wudhu and pray.
You don’t need to wash it off except before praying and not every time it is discharged.