I have seen FAS, quite a few times. And the mothers did not drink what I would consider to be "moderate".
I did drink when I was pregnant with both of mine. 1/2 a glass of champagne at a wedding. The odd 1/4 wine 3/4 soda when out. Even Lemon/lime/bitters has a fraction of alcohol. That is what I consider "moderate". Less than 1 standard drink a month, even.
So shoot me for being an "educated, middle class, drinking when pregnant" woman. You cannot tell me that I put my children at risk of FAS.
If moderate alcohol caused that kind of damage, most of my generation would be impaired - our mothers all drank when they were pregnant with us.
The average baby-in-utero is more at risk every time the mother gets into a car than they are from the level of drinking I and my friends indulged in.