Small for Gestational Age (SGA) is a term that refers to an infant or fetus in the uterus that is smaller in size than is expected for an infant or a fetus of similar gender, genetic heritage, and gestational age. SGA or Intrauterine Growth Restriction (IUGR) are usually identified by ultrasound before birth or an examination after birth. Birth weight below the 10th percentile of the population, corrected for gestational age, has been the most widely used definition of SGA and IUGR. Neonatal growth restriction is recognized as a syndrome encompassing small size as well as specific metabolic abnormalities including hypoglycemia (low blood sugar level), hypothermia (low body temperature), and polycythemia (increased level of red blood cells).