Fetus Weight Percentile

A teratogen is any substance or influence that interferes with the normal development of a fetus and causes birth defects. Alcohol is the most commonly used teratogen in the United States. (The Merck Manual, 18th Edition. High-risk pregnancy: risk factors. 2006:2186-91)

Drinking alcohol during pregnancy can lead to a number of developmental deficits in a newborn; these defects are collectively known as fetal alcohol spectrum disorders (FASD).