Anatomy scan

Exactly 3 weeks today I have my anatomy scan! Will they be able to tell me right away if everything looks good, or does it need to be reviewed first? I want to announce after I find out what I'm having, but not before I'm told if everything looks okay. I just want to be extra safe this time. Last year I miscarried at 13 weeks after announcing at 12 weeks 3 days.. I was too impatient to wait until my genetic test results came back and I really wish I did! I don't want to announce as soon as I leave the doctors and then get a call a few days later that something is wrong.