Pounds per square inch. The pound per square inch or, more accurately, pound-force per square inch (symbol: lbf/in2; abbreviation: psi) is a unit of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an area of one square inch:
small for gesÂ·taÂ·tionÂ·al age. Infant whose birth weight is below the tenth percentile for gestational age. small for gestational age. SGA. 1. Term describing an infant whose birth weight is at or below the 10th percentile, as correlated with the number of weeks in utero on the intrauterine growth chart.
An extremely low birth weight (ELBW) infant is defined as one with a birth weight of less than 1000 g (2 lb, 3 oz). Most extremely low birth weight infants are also the youngest of premature newborns, usually born at 27 weeks' gestational age or younger. Infants born with a birth weight less than 1500 g are defined as very low birth weight (VLBW) infants. Approximately 3,952,841 US births were reported in 2012.Low birth weight (< 2500 g) was noted in 7.99% of the births, and VLBW was noted in 1.42% of all births.