Alcohol and drug abuse during Pregnancy

A mum once told me that she had been advised to give her colicky baby a spoonful of beer. Another shared that a glass of beer helps with milk production. There is a lot of conflicting information that you may get during pregnancy but one advice you are bound to hear often is that alcohol is not good for the growing baby. Why is this so? What effects does alcohol have on your baby? Is there a ‘safe’ amount that you can take?