Turner Syndrome

How common is it for your baby to be diagnosed with Turner Syndrome or Edwards Syndrome after 12 weeks? I don’t know if I want to do the genetic testing but I’m so afraid of this happened and having a late miscarriage. All of my scans have looked great so far but I know that doesn’t really mean anything. I’m 11w1d. Will they be able to tell if there’s something wrong on my 12 week scan?