My father is affected by it but we didn't know that it could be passed down at the time. I had a blood test that came back abnormal. It said that there was a 1.18 chance of the baby having smith-lemli-opitz syndrome so doctors did an amnio test. I saw gene and fetal medicine specailists and after the amnio and the scans all came back normal they questioned my family history. That how we found out what it was (as well as having it comfirmed by another test) and why the uE3 levels had come back so low.