[Study of weight deficiency in a representative sample of newborns]

A study of a representative sample of 11,330 newborns allowed to establish the distribution of birth weights in terms of gestation-age. The comparison with Lubchenco's curves shows important differences since the 10th percentile of the American curve is below the 3rd percentile of the French sample for prematures. The use of a technique of multivariant analysis distinguishes groups with low and high risks of prematurity and hypotrophy. The distinction is more obvious for the first group than for the second. The study of the rate of early neonatal mortality in terms of weight and gestation-age, led to individualize the risk related to hypotrophy from that related to prematurity.