Fetal Alcohol Spectrum Disorder covers a number of birth defects that falls under Fetal Alcohol Spectrum Disorder. These birth defects are caused when the mother drinks during her pregnancy. According to the March of Dimes, 40,000 babies are born each year with some degree of "alcohol-related damage." Fetal Alcohol Syndrome is the most common known cause of intellectual disability, and it is the only cause that is entirely preventable.
When the mother drinks, the alcohol passes through her system and into the baby through the placenta. Since the baby is much smaller and not as well developed, the alcohol remains in the baby’s body for a much longer period of time, at much higher levels. This can cause life-long damage to the child.
No level of alcohol use during pregnancy is safe. Since a woman may not know for several weeks or months, anyone who may be pregnant or is trying to get pregnant, should not use alcohol in any amount.March of Dimes - Alcohol & Drugs