Low birth weight (LBW) is defined as a
birth weight of a liveborn infant of less than 2,500 g (5 pounds 8 ounces) regardless of gestational age. Subcategories include
very low birth weight (VLBW), which is less than 1500 g (3 pounds 5 ounces), and
extremely low birth weight (ELBW), which is less than 1000 g (2 pounds 3 ounces). Normal weight at term delivery is 2500–4200 g (5 pounds 8 ounces – 9 pounds 4 ounces).