The Centers for Disease Control and Prevention (CDC) reported that 3 million of American women ages 18 to 45 are at risk for alcohol-exposed pregnancy.

The federal health agency says that "Sexually active women who stop using birth control should stop drinking alcohol, but most keep drinking."  

CDC claims that even during the very first few weeks of pregnancy, alcohol can cause damage to the baby.  Alcohol per se is harmful.  A metabolite of alcohol called acetaldehyde, which is very chemically reactive, is a human carcinogen that can initiate carcinogenesis.