low birth weight
(loh berth wayt)
A term used to describe an infant born weighing 5.5 pounds (2500 grams) or less. A low birth weight may occur when an infant is born too early (premature). These infants may have an increased risk of serious health problems. Smoking cigarettes, being exposed to secondhand tobacco smoke, drinking alcohol, and taking certain drugs during pregnancy can increase the risk of having an infant with a low birth weight.