Extra-uterine growth restriction (EUGR) is frequently seen in premature and critically ill infants. Even though advancements in neonatal intensive care have improved the survival of these high-risk infants, many new questions have emerged about the relationship between postnatal growth and neurodevelopmental outcome of these infants. EUGR has traditionally been ascribed to caloric restriction during postnatal periods of critical illness. Nutritional compromise, particularly during the first few weeks of life, may affect the overall growth and could also cause long-term neurodevelopmental impairment. The accidental and premature interruptions of pregnancy could also alter the normal mobilization and utilization of major nutrients from the ways that would have otherwise occurred during the last trimester of pregnancy, which is normally a period of maximal in utero growth. In this article, we review our current understanding of defining EUGR, various risk factors for EUGR, its pathophysiology, and possible ways with which our current healthcare protocols could prevent EUGR.
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