Sure, you've seen a pregnant Betty Draper looking glamorous on "Mad Men" as she smokes a cigarette and sips a martini. If you're a child of the '70s or earlier, your own mother may even have assured you that "everyone" drank during their pregnancies back then. Mom's well-meaning advice aside, the American College of Obstetricians and Gynecologists (ACOG) maintains that there is no safe amount of alcohol to consume during pregnancy, or even while trying to conceive. This is because any alcohol the mother takes is directly absorbed by the baby through the placenta – and the baby's liver isn't developed enough to break down alcohol.
Heavy drinking during pregnancy is known to cause miscarriage, stillbirths, low birth weight, and fetal alcohol syndrome, a collection of disabilities that range in severity but may include abnormal facial features, growth problems, behavioral issues, and mental or intellectual difficulties [sources: ACOG, CDC]. While some research has suggested that light drinking during pregnancy poses no significant risk to the fetus, even the authors of those studies stop short of advocating that pregnant women should drink alcohol [source: Brooks].