I was reading a little story about how the pilgrims stopped at Plymouth Rock because they ran out of beer- beer being the drink of choice because water was usually contaminated and didn't store well. Is there much evidence of fetal alcohol syndrome then? Or any other severe health effects in the population?
According on one study of 400,000 women, no adverse affects were found when the women drank < 8.5 drinks per week. Other studies have found no ill effects when women had fewer than 14 drinks per week. So, it's really the major alcoholics that struggle with this. (Though, the exact amount of risk is unknown, so the safest thing to do is follow standard advice and not drink).
The pilgrims and most others would be opposed to the idea of being completely drunk on a regular basis, and so FAS probably wasn't an issue, especially considering that much of the beer was "small beer", which has a lower alcohol percentage than "normal" beer.