This was very interesting:

An analysis of seven major medical research studies involving over 130,000 pregnancies suggests that consuming two to 14 drinks per week does not increase the risk of giving birth to a child with either malformations or fetal alcohol syndrome.
Negative effects appear to be related to relatively higher levels of consumption per occasion, and hence, to higher blood alcohol content levels. Thus, it appears to be very important never to consume more than one drink in any one day while pregnant.
It was told to my SIL when she heavily drank in the early stages of her pregnancy (she was unaware she was pregnant). The Drug and Alcohol abuse centre almost laughed at her (not in a horrible way) when she said she had concerns. So I found that quite interesting. I think our perception may have gone from careless to over-cautious. BUT I also understand why being over-cautious is better for some people, so please don't think I am knocking anyone at all. It's just good to have some accurate information available. And please don't think that I'm saying that those that did have a drink or two weren't cautious enough.

Hope I've made sense and not offended anyone :/