Neonatal Hypoglycemia

Lower blood glucose values are common in the healthy neonate immediately after birth as compared to older infants, children, and adults. These transiently lower glucose values improve and reach normal ranges within hours after birth. Such transitional hypoglycemia is common in the healthy newborn. A minority of neonates experience a more prolonged and severe hypoglycemia, usually associated with specific risk factors and possibly a congenital hypoglycemia syndrome. Despite the lack of a specific blood glucose value that defines hypoglycemia, concern for substantial neurologic morbidity in the neonatal population has led to the generation of guidelines by both the American Academy of Pediatrics (AAP) and the Pediatric Endocrine Society (PES). Similarities between the 2 guidelines include recognition that the transitional form of neonatal hypoglycemia likely resolves within 48 hours after birth and that hypoglycemia that persists beyond that duration may be pathologic. One major difference between the 2 sets of guidelines is the goal blood glucose value in the neonate. This article reviews transitional and pathologic hypoglycemia in the neonate and presents a framework for understanding the nuances of the AAP and PES guidelines for neonatal hypoglycemia.