Alcohol in the blood stream of the mother crosses the placenta and reaches the fetus. Fetal alcohol syndrome results in growth failure after birth, reduced IQ, and malformation of facial features. Your body's ability to break down alcohol depends on your weight, recent food intake, physical condition, and gender. A larger person can usually tolerate more alcohol. Recent food intake will slow the digestion of alcohol, thereby minimizing it's effects.
Men generally tolerate more alcohol than women.
It is believed that gender and genetic factors determining alcohol tolerance are related to a person's ability to produce the enzyme that helps digests alcohol. If you produce more of this enzyme, less of what you drink reaches the blood stream in the form of alcohol and more arrives already broken down. Therefore, a person with more of this enzyme can tolerate more alcohol without the effects on the central nervous system . The U.S. Dietary Guidelines suggest that if you drink alcohol, do so in moderation. Never drink alcohol and drive a car.