Consequences of intrauterine growth and early neonatal catch-up growth.

The long-term consequences of small size at birth have been well described during the last 2 decades. It is important to assess the fetal growth velocity and to recognize that newborns may have growth restriction even with a normal birth weight. Intrauterine growth retardation suggests decreased growth velocity in the fetus as the result of a certain pathophysiologic process. An infant born after a short period of intrauterine growth retardation may not necessarily be small for gestation at birth. Several cohorts of adults born after a normal intrauterine growth have been followed for long term. Greater weight gain and fat mass early in life after thinness at birth are risk factors for overweight and cardiovascular diseases. Other risk factors include prematurity, bottle feeding, and tobacco exposure in utero. Early catch-up growth after fetal growth restriction replaces the organism on its growth trajectory with similar gain in weight and height.