They might be able to see some markers in the ultrasound if there are any. My daughter that I lost had a clubbed foot, a heart defect, a dilated kidney ureter, and some other things that I can't recall at the moment. Unfortunately for me, they didn't point any of that stuff out til my very last ultrasound at about 32 weeks, just days before she passed. Hopefully your quad screening is wrong.
First off im sorry for lost.. Yes it was the quad screening I go for my 20 week ultrasound Monday
Was it just the quad screening or was it the detailed blood test that also tells the gender? Because the quad screening has a habit of having false positives. I got a positive on the quad screening with my first baby for Trisomy 18. An amniocentesis did confirm that she actually did have it after she passed away when I was 8 months pregnant with her.