Quad Test Results - Bad News

Kaitlyn

What would be other reasons for Quad test results to come back high risk, but baby doesn't have down syndrome?

I won't be able to speak with a genetic counselor until 8/12 and just wish I had more knowledge of results.

I received a 1:18 chance for down syndrome on my Quad test, but would like to know what other reasons could cause this result if say the baby didn't have down syndrome.